Timothy H. Heaton
Department of Geology, Brigham Young University, Provo, Utah 84602
ABSTRACT
The fossil assemblage represents a much more boreal community than the present local fauna. Fish, Ondatra zibethicus, and Mustela cf. vison, which require perennial water, were recovered, as were Ochotona princeps, Lepus cf. americana, Microtus cf. pennsylvanicus, Vulpes vulpes, and Martes americana, which have also been extirpated from the Snake Range. Marmota flaviventris, Neotoma cinerea, cf. Cervus elaphus, and Ovis canadensis were recovered but now occur only at higher elevations in the range. Extinct taxa recovered are Smilodon cf. fatalis, Equus species, Camelops cf. hesternus, Hemiauchenia cf. macrocephala, cf. Symbos cavifrons, and a new species of Brachyprotoma, herein named B. brevimala. This is the first recovery of Brachyprotoma from the western United States.
It is uncertain if native Americans knew of Crystal Ball Cave, for no ancient human artifacts were found in this study. The cave was discovered by the late George Sims of Gandy in February, 1956. He found the original 3 foot (1 meter) diameter entrance that leads into a large chamber (see figure 3). The original east entrance was enlarged, the north entrance was blasted out through a soil-filled passage at the other end of the cave (see figure 3), and other improvements were made by Cecil R. and Jerald C. Bates of Gandy, Utah and Thomas E. Sims of Elko, Nevada (J. C. Bates 1983 personal communication).
Herbert H. Gerisch and Robert Patterson collected bones from Site 1 (see figure 3) in 1956 that they donated to the Los Angeles County Museum (H. H. Gerisch 1983 personal communication). Later Michael Stokes of the Los Angeles County Museum collected additional specimens from Site 1. These early collections consisted of float only and included bones of extinct horses and camels. On at least one of these early expeditions, some specimens were also collected from Gandy Mountain Cave, a smaller cave that lies about 1/4 mile (0.4 km) south of and 100 feet (30 meters) higher than Crystal Ball Cave. Specimens from these two caves are indistinguishable in the Los Angeles County Museum collection because the cave in which each specimen was recovered was not recorded. I dug several test pits in Gandy Mountain Cave in 1981 and found preservation to be poor and specimens to be few and probably all Recent. So although some specimens were collected from Gandy Mountain Cave, they are not considered in this study, except some which may be among the Los Angeles County Museum collection.
The first extensive collecting in Crystal Ball Cave was done in 1977 by Wade E. Miller and his students from Brigham Young University who used fine screens to obtain thousands of specimens (all from Site 1). Miller (1982) described this investigation and listed the genera identified in a report on vertebrate fossils from Lake Bonneville deposits. Wade E. Miller and I operated similar collecting projects in 1981 and 1982 (Sites 1, 2, and 3), and I wrote a preliminary report on this study (Heaton 1984). Crystal Ball Cave is Los Angeles County Museum locality 4534 and Brigham Young University vertebrate paleontology locality 772; the specimens from the cave are cataloged as LACM 123655-123711 and BYUVP 5300-8888, 8911-8933. Taxa recovered are listed in table 1.
The Crystal Ball Cave assemblage is the first late Wisconsinan age fauna to be described from the state of Utah. Although Utah has extensive Pleistocene deposits from Lake Bonneville, surprisingly few vertebrate fossils have been recovered from them (Miller, 1982). The only other Pleistocene assemblage that has been described from Utah is the Silver Creek fauna of north-central Utah, 14 miles (22 km) east of and 1,200 feet (360 meters) above Lake Bonneville's highest level and of late Sangamon to early Wisconsinan age (Miller 1976).
The nearest described Pleistocene vertebrate localities are four shelters located in Smith Creek Canyon, White Pine County, Nevada, 9 miles (14 km) south of Crystal Ball Cave. New species of mountain goat (Stock 1936), eagle (Howard 1935), and gigantic vulture (Howard 1952) were described from Smith Creek Cave, the primary site. Literature on the Smith Creek Canyon sites includes a description of the avifauna by Howard (1952), the micromammalian fauna by Goodrich (1965), the herpetofauna by Brattstrom (1976), the whole fossil assemblage by Miller (1979) and Mead et al. (1982), and the archaeology by Bryan (1979), Harrington (1934), and others. Although the Crystal Ball Cave fauna is chronologically and geographically close to that of Smith Creek Canyon, it differs in having its fossils deep in the cave, and this has resulted in significant differences between these assemblages. Crystal Ball Cave, for example, has more abundant mammal fossils but less abundant bird fossils than the Smith Creek Canyon sites.
The Crystal Ball Cave assemblage contains only small bones with a maximum length of about 10 cm and maximum weight of about 50 grams. This has caused some problems in identifying the large species since only the smallest elements, which have rarely been considered in other studies, are represented. The assemblage, however, is very large and is important since few assemblages of late Pleistocene age have been reported from the region. The size of this assemblage and the time restraints upon the project have limited the depth to which each taxon could be studied. For taxa with large numbers of specimens, only the best specimens were considered. Additional work could turn up more species, and statistical studies on the more abundant taxa could yield much additional information.
I have recognized four distinct stages of the cave's history: 1) a period of dissolution of limestone to form the cave, 2) a period of precipitation forming a layer of large calcite crystals ("nail head" spar) up to 1 foot (0.3 meters) thick on the cave walls, ceiling, and floor, 3) a period of partial dissolution of these crystals in the upper portions of the cave, the appearance of joints that cut the large calcite crystals, and the dislodging of breakdown from the ceiling of the large entrance room, and 4) the formation of vadose calcite speleothems and influx of sediment and fossils from outside the cave.
The beginning of stage 1, the dissolution of the cave, is of uncertain date. Davis (1930) demonstrated that limestone dissolution to form caves occurs predominantly in a thin zone just below the water table which is rich in carbon dioxide from groundwater percolating down from the surface. Once it reaches the water table, this groundwater dissolves the rock as it moves very slowly down the water table slope (Davies 1960). This appears to be the case in Crystal Ball Cave, since no scalloped or stream-cut passages are present to suggest the presence of fast-moving water expected in an above water table origin (Malott 1938, Myers 1969). The cave tends to parallel the strike of the beds and is relatively horizontal, as would be expected if the cave were formed at the water table. Green (1961) cited evidence that some caves in western Utah predate the tilting associated with the Basin and Range uplift. The fact that Crystal Ball Cave is roughly horizontal and parallel to the strike of the beds suggests that it postdates this tilting. But since the cave is high in a small isolated hill, considerable uplift and/or erosion must have taken place since the cave was at the water table. The cave does not parallel the present land surface as the water table tends to do (Myers 1969), and this further suggests that much overburden has been removed since the original dissolution of the cave.
Stage 2, the precipitation of large calcite crystals, represents a different groundwater environment than the preceding dissolutional stage. It is generally agreed that such "nail head" spar forms in still, calcite-saturated water where nucleation centers are free to grow into large euhedral crystals (Hill 1976). This shift from dissolution to precipitation does not necessarily represent a significant change in the level of the water table, but it does represent the drastic reduction in the carbon dioxide content of the groundwater necessary for calcite precipitation (Moore and Nicholas 1964). Several vertical cavities (domes) extend upward into the cave ceiling, and these predate the calcite precipitation because they are partly filled by it. Moore and Nicholas (1964) cited evidence that such domes form late in cave dissolution and provide more direct water and air connections to the surface. Myers (1969) stated that they are of vadose (above water table) origin and caused by vertical seepage. Perhaps the formation of these domes allowed gas exchange between the groundwater in the cave and the surface permitting carbon dioxide to escape and calcite to be precipitated.
Stage 3 includes several events which are not chronologically separable. Some of the calcite crystals in the roof of the cave are completely dissolved, and locally some of the limestone bedrock underneath it is also. This is especially evident in the aforementioned domes. Joints and breakdown, both of which cut the previously formed calcite crystals, probably represent one or several earthquakes. If any uplift postdates the cave's origin, it probably occurred during this stage. These cracks and breakdown blocks were later filled and covered by the speleothems of stage 4, showing their chronologic relationship.
Stage 4 postdates the loss of voluminous standing water in the cave and the opening of entrances large enough to allow considerable gas exchange and sediment into the cave. Vadose speleothems such as the stalactites, columns, and rimstone pools found in Crystal Ball Cave form subaerially in caves having enough gas exchange with the surface to allow carbon dioxide to escape from the dripping groundwater (Moore and Nicholas 1964). Near the east entrance of the cave some small columns have formed upon and been partly covered by sediment coming in from the entrance, showing the concurrence of these events. The vertebrate material under study entered the cave during stage 4 when cave opening(s) were sufficiently large to allow their entry and dry conditions allowed their preservation; therefore cave stages 1 through 3 predate the oldest fossils.
Twelve sediment samples were collected at sites throughout the cave and screened to determine the degree of sorting. All samples are poorly sorted, but samples farthest from known entrances tend to have a higher percentage of fine particles. Particles under 0.0024 inch (0.061 mm) in diameter make up over half the weight percent of three such samples. Samples were placed in hydrochloric acid to remove all calcite. Sediment from Site 1 (see figure 3) is composed of about 80% calcite and 20% very fine but poorly sorted clastic grains, namely quartz, mica, and an unidentified ferromagnesian mineral. Larger clastic grains were found in samples closer to each entrance and comprised greater portions of the sediment.
The calcite portion of the sediment is composed of both crystal fragments, probably derived from broken "nail-head spar," and cryptocrystalline caliche-like crust associated with clastic fragments, almost certainly precipitated in the cave. The clastic fragments could have been washed in, blown in, brought in by animals, or been released from the cave walls as impurities in the limestone. The sediments at Site 1 show no sign of ever having been wet except in some areas where they have been cemented with calcite. But water runs in through the east entrance during storms filling the large entrance chamber with mud. Wind gusts can be quite strong through the cave during storms, but only because the north entrance was opened by man. The importance of these factors is difficult to determine, but the fact that the bulk of the sediment far inside the cave is calcite demonstrates that the sediments are mostly derived from within the cave by weathering of the limestone and calcite crystals rather than from outside sources.
On early collecting trips most of the field time was spent digging through the sediments and collecting specimens by hand. Sediment was also taken to the lab in bags and screened in order to recover smaller bones and teeth. After using this method for several trips, the collection had overwhelming numbers of rodent and lagomorph fossils, but bones of larger mammals were few. So on the last collecting trip large volumes of cave sediment were screened inside the cave with a coarse screen, and the number of larger bones in the collection was thereby more than doubled.
Little laboratory preparation was necessary with the larger Crystal Ball Cave fossils. A few required removal of hardened dirt or calcite. All were washed to remove dust. Considerable time was spent manually separating small bones and teeth from cave sediments. This was done in the laboratory with forceps after the sediments had been washed through a fine screen and allowed to dry. Approximately 35 cubic feet (1 cubic meter) of cave sediment was prepared in this manner, and virtually all the bone was removed.
Because of the great abundance of small mammal fossils recovered, only the skulls and jaws were studied. All identifiable material was used for larger mammals because they were not as well represented and because few dental elements were recovered. Identification was made by comparison to Recent specimens housed at the Brigham Young University Monte L. Bean Museum, fossil specimens housed at the Brigham Young University Vertebrate Paleontology Laboratory, and by extensive use of the literature.
Small living mammals were captured inside Crystal Ball Cave and around Gandy Spring at the base of Gandy Mountain. This trapping was not extensive, but it did indicate what species are abundant in and around the cave. The species trapped are recorded in table 1. Jerald C. and Marlene Bates of Gandy (1983 personal communication, 1984 personal communication) were interviewed for additional information about the modern local fauna and recent history of the cave including modification by man.
Four bone samples were sent to Geochron Laboratories, Cambridge, Massachusetts, for carbon-14 dating. Because of the small size of bones in the assemblage, these samples (which included some of the largest recovered) were just over 25 grams, the minimum weight suggested for dating. Two were of small extinct horses: a thoracic vertebra (BYUVP 7687) and a distal metapodial epiphysis (BYUVP 7568); and two were fragments of unidentified limb bones of large mammals. Geochron Laboratories cleaned and washed the four samples in acetic acid to remove adhering materials then crushed them and soaked them in agitated acetic acid for 24 hours to remove normal carbonates. The samples were then hydrolized under vacuum with hydrochloric acid to dissolve bone apatite and evolve its carbon dioxide for collection. The carbon dioxide samples were converted to methane and counted in a low background beta counter (with C-13 correction), and dates were based on the Libby half life (5570 years). The ages reported are listed in table 2. The oldest date of "over 23,000 Y.B.P." was given because no C-14 was detected in that sample.
The oldest date of 23,000+ Y.B.P. gives a minimum age for the time fossils first entered the cave. The youngest horse bone date of about 19,000 Y.B.P. gives a maximum age for the loss of that species from the area, although other studies have shown that small horses lived beyond 10,370 Y.B.P. in Idaho and until about 8,000 Y.B.P. in Arizona and Alberta, Canada (Kurten and Anderson 1972, 1980, Martin 1967). Otherwise the four dates give only a general age for the assemblage and provide no information about the antiquity of individual taxa. The fact that all four dates are over 12,000 Y.B.P. suggests that bones, at least of large mammals, may have been deposited more frequently during the late Pleistocene than during the Recent. If so, this could be due to a greater abundance of the animals themselves, a change in what animals (or other processes) deposited the fossils, or the former presence of larger or additional entrances.
Thirty radiometric dates have been reported from the Smith Creek Canyon sites (Thompson 1979, Thompson and Mead 1982, Valastro et al. 1977), and they demonstrate that accumulation of fossils there was concurrent with fossil deposition at Crystal Ball Cave. The two oldest Smith Creek dates are 28,650 Y.B.P. (Smith Creek Cave) and 27,280 Y.B.P. (Ladder Cave), which correlate well with the date of "over 23,000 Y.B.P." from Crystal Ball Cave. The other 28 Smith Creek Canyon dates are younger than 18,000 Y.B.P. with the majority being from 10,000 to 13,000 Y.B.P. The mean age of the four dated Crystal Ball Cave specimens is considerably older than the mean age of dated specimens from any of the Smith Creek Canyon sites, suggesting that its major period of fossil deposition was earlier; but a sample size of four dates is not statistically significant enough to demonstrate this.
In addition to Lake Bonneville, many pluvial lakes filled the valleys of Nevada including one just west of the Snake Range, 18 miles (30 km) west of Crystal Ball Cave (Mifflin and Wheat 1979). Based on studies of temperature and precipitation correlation, Mifflin and Wheat (1979) estimated that development of pluvial lakes in the area involved a temperature decrease of 5 F (3 C). Lower temperatures and higher annual precipitation caused floral boundaries to move lower in elevation and latitude during the Wisconsinan glacial (Thompson and Mead 1982, Wells 1983). This shift had a dramatic effect on small boreal mammals in the Great Basin because it allowed them to disperse between ranges, whereas now the intermontane basins act as absolute barriers (Brown 1971, 1978, Harper et al. 1978). Brown (1971, 1978) demonstrated that distribution of small boreal mammals is relectual from the Wisconsinan glacial and not a case of colonization-extinction equilibrium. The Crystal Ball Cave fauna shows what taxa have been extirpated from the Snake Range since the Wisconsinan glacial and documents northward shifts in the ranges of several species at the close of the Pleistocene.
Another striking feature of the late Pleistocene is the well-documented megafaunal extinction. At the end of the Wisconsinan glacial 41 species of large mammals went extinct--3 times more than at the end of any of the other Pleistocene glacials (Kurten and Anderson 1980). Different workers have attributed this to the rapid post-glacial climatic shift (Martin and Neuner 1978, Webb 1969) and to overkill by Early Man (Martin 1967, Mosimann and Martin 1975). The Crystal Ball Cave assemblage contains several of these extinct taxa, but the fact that it lacks human association and stratigraphic control makes it unable to provide any substantial data to resolve this controversy.
Consideration needs to be given to the role Crystal Ball Cave played as a shelter and the way fossils got into the cave. When the cave was discovered in 1956, the east entrance was a 3-foot (1-meter) diameter opening in solid rock, half filled with soft soil, which sloped downward into the large entrance chamber (see figure 3). Several 1-foot (0.3-meter) diameter entrances (which are often filled with woodrat nesting material) also exist just north of the east entrance. The north entrance was completely filled with debris, which if removed could make it 8 feet (2.5 meters) high and 20 feet (6 meters) wide. It could have been a large important entrance when the earlier bones were being deposited, but several factors preclude this. First, there are very few fossils in the deep dry sediments of the north half of the cave; the rich bone deposits are in the south half. Second, the fossil assemblage provides no evidence that there ever was a large entrance since large mammals are represented only by their smallest elements. If the north entrance ever was large it was probably prior to deposition of the fossils under study.
Neotoma lepida, Peromyscus maniculatus, and Plecotus townsendii were captured live inside the cave, so their presence in the assemblage is easy to explain. Other small mammals could also have lived in the cave or used it as a shelter. Small carnivores and scavengers could have brought their prey into the cave to eat. The presence of only the smallest isolated elements of large mammals suggests that these bones were brought into the cave individually after the carcasses deteriorated. Small carnivores could have contributed to this, but it is my opinion that these bones were taken into the cave primarily by wood rats, since they are known to take materials into the cave now and since all the bones in the assemblage are small enough for a wood rat to transport. Because the cave has small entrances and because the bones are found far within the cave, it is very unlikely that birds transported prey inside. There is also no evidence that prehistoric humans brought material into Crystal Ball Cave. This suggests that the species found in the assemblage lived and died in or near the cave and were not transported long distances, as could have occurred at Smith Creek Cave (see Bryan 1979, Harrington 1934).
It is unusual for caves to have their richest bone deposits far inside the cave rather than near an entrance. The east entrance takes in water during storms, and other areas are damp from seepage. Sites 1 and 2, which contain the richest bone deposits, are in one of the driest areas of the cave and are just outside the zone of total darkness when the sun shines through the east entrance. North of Sites 1 and 2 the passage constricts and enters total darkness but remains dry. Wood rat nests are particularly common at Sites 1 and 2, which helps explain why rich bone deposits are present if wood rats play an important role in getting them there. The extremely dry conditions at Sites 1 and 2 and their proximity to the east entrance, which I consider the primary entrance, are probably the reason why these sites have been so productive. Rarity of fossils nearer the east entrance is probably due to poorer preservational conditions and poorer sites for wood rat dwellings. Lack of rich bone deposits in the northern half of the cave is probably due to constricted passages and greater distance from a late Pleistocene entrance.
Kingdom Plantae
Material--Two stem fragments.
Material--One branching stem fragment.
Material--One group of involucres, 4 single involucres.
Material--Four involucres on stem fragments.
Material--Two stem fragments, 2 stem fragments with empty seed capsules, 4
empty seed capsules.
Material--Twelve spines.
Material--One branching stem fragment, 4 straight stem fragments, 56 leaves
and partial leaves.
Material--Two fruits.
Material--Three connected fruits, 3 rachis fragments.
Discussion--About 250 small plant fragments were recovered from the Crystal
Ball Cave sediments by the same process that small bones and teeth were
recovered. From among them Howard C. Stutz (1984 personal communication), a
botanist at Brigham Young University, identified the above taxa. All of the
taxa identified still live in the immediate area of Crystal Ball Cave (partly
because a sample of plants from immediately around the cave comprised most of
the comparative material), so they do not document any floral changes since
the Pleistocene. Further research could turn up additional taxa since not all
the plant fragments were identified.
The great abundance of Symphoricarpos compared to the other plant taxa
recovered is noteworthy. H. C. Stutz (1984 personal communication) found a
thicket of Symphoricarpos at the bottom of a cliff in the nearby House Range
which was full of rodent nests and burrows. This suggests that this plant is
a favorite nest building material for rodents, and wood rats may have brought
a lot of it into Crystal Ball Cave for that purpose.
No pollen analysis has been done at Crystal Ball Cave, and no pollen was
noticed in the cave sediments studied. A more extensive search could turn up
pollen, however, and since plant fragments are rare in the sediments, it
could help identify what plants inhabited the area during the Pleistocene.
Material--Nine complete shells ranging from 3 to 10 mm in diameter.
Discussion--These land snails, which still inhabit the Snake Range, live in
moister conditions than those at Crystal Ball Cave today (Chamberland and
Jones 1929), so they are probably late Pleistocene or early Recent in age.
Since there are only nine specimens, they were probably never abundant near
the cave and may have even been transported some distance before being
deposited.
Material--Partial dried shell.
Discussion--Pill bugs are native to North America (S. L. Wood 1984 personal
communication), and little work has been done on them. Representatives of
several families including family Armadillidae presently live in Utah, but
the partial specimen did not allow further identification. These terrestrial
crustaceans inhabit moist recesses throughout Utah and Nevada today, so the
presence of this specimen is not surprising although little can be said about
its age.
Material--Complete dried specimen.
Discussion--This small beetle lives in cattle dung and was introduced from
Europe in Recent times (S. L. Wood 1984 personal communication). It is
therefore Recent in age and has little significance to the assemblage.
Material--Thirty-seven amphicoelous vertebrae ranging from 1 to 5 mm in
diameter and length (BYUVP 7939-7973).
Discussion--Presently the closest water body to Crystal Ball Cave is Gandy
Spring on the south side of Gandy Mountain. This spring emits voluminous warm
(81 F, 27 C) water which is high in calcium (J. C. Bates 1983 personal
communication). Small minnows were the only native fish found living in the
stream that exits Gandy Spring, but bass and blue gill were introduced in the
1960's and still survive; carp are also found in reservoirs in the area (J.
C. Bates 1984 personal communication). Mead et al. (1982) reported Salmo and
Gila from nearby Smith Creek Cave which is higher in elevation and farther
from a perennial water source than Crystal Ball Cave, and Smith (1978) and
Smith et al. (1968) reported Pleistocene fish from Lake Bonneville
deposits.
A dichotomy in the size of the fish vertebrae from Crystal Ball Cave suggests
that at least two species are represented, but no attempt at generic
identification has been made. The possibility that these vertebrae are Recent
cannot be eliminated, but they probably represent fish that lived in Lake
Bonneville when it was at or near the Bonneville level, or in perennial
Pleistocene streams in the area. In any case they had to be transported up
Gandy Mountain to the cave site. Carnivores or scavengers could have done
this, and wood rats could have taken them inside the cave.
Material--Two hundred and sixty-five lizard and snake jaws (BYUVP 8004-8217).
Postcranial material is also represented but has not been separated from that
of mammals.
Discussion--The reptile specimens have not yet been studied but will be
reported in a future paper by Jim I. Mead and Timothy H. Heaton. The reptiles
recovered from the deeper levels of Smith Creek Cave demonstrate that their
present distribution in the Great Basin is more ancient than previously
believed (Brattstrom 1976, Mead et al. 1982). The large number of reptile
jaws from Crystal Ball Cave will help establish what species have been
extirpated from the area, but unless dated individually, they will not help
establish the antiquity of their ranges.
Material--Six hundred and eleven specimens representing all skeletal elements
of small passerines and skull and vertebrae fragments of larger forms (BYUVP
6606, 8301-8888, 8911-8933, LACM 123655).
Discussion--The bird specimens have not yet been studied but will be reported
in a future paper by Steven D. Emslie and Timothy H. Heaton. Miller (1982)
reported ? Aquila from Crystal Ball Cave from among this same material. Based
on their large size, three bird vertebrae fragments (BYUVP 8326-8328) can
possibly be assigned to the extinct Teratornis incredibilis, originally
described from nearby Smith Creek Cave (Howard 1952).
Material--One maxilla pair with all teeth (BYUVP 5321). Another 5 partial
maxillae and 27 partial dentaries (some with teeth, BYUVP 5300-5320,
5322-5332) were recovered that cannot be generically identified but compare
favorably with Sorex.
Discussion--Identification was based on the presence of 5 unicusp teeth
behind the upper incisor, the first 4 of which taper slightly in size
posteriorly and are visible laterally, and the last of which is tiny,
peglike, unpigmented, and not visible labially. Microsorex and Blarina also
have 5 unicusp teeth in each maxilla, but Microsorex has only the first 3
visible laterally and Blarina has the third and fourth of subequal and
smaller size than in Sorex. Notiosorex and Criptotis, the other two North
American genera, have only 3 and 4 unicusp teeth in each maxilla respectively
(Hall 1981). All the other soricid specimens are either lower jaws and teeth,
which I was unable to distinguish at the generic level, or are maxillae
without the diagnostic unicusp teeth. All these soricid specimens compare
well with S. vagrans and S. palustris, which presently live in the region of
the cave (Hall 1981), but no dental character could be found to distinguish
them.
Material--Two palates without teeth (BYUVP 5340, 5357), anterior portion of
right maxilla with P4/, M1/ (BYUVP 5338). Twelve right dentaries (BYUVP 5336,
5341-5346, 5352, 5353, 5358-5360) and 12 left dentaries (BYUVP 5339,
5347-5349, 5354-5356, 5361-5364, 5366) were recovered which are Myotis or
Plecotus.
Discussion--Myotis maxillae have the diagnostic presence of two
Material--Twenty-four dentaries were recovered of Myotis and/or Plecotus (as
listed and discussed above).
Discussion--Plecotus townsendii is the only bat reported living in the cave.
Specimens were captured by Halliday (1957) and by myself in 1982 and 1983.
Halliday (1957) and other workers have referred this bat to Corynorhinus
rafinesquii, but Handley (1959), in his synthesis of the big-eared bats,
considers both Corynorhinus and Idionycteris as only subgenera of the
European genus Plecotus. He also regards P. rafinesquii (presently in
southeastern U.S.) and P. townsendii (presently in western U.S.) as two
distinct species. P. mexicanus, the third living species of the subgenus
(Corynorhinus), and P. hyllotis, the only member of the subgenus
(Idionycteris), both inhabit Mexico and north into the southern tip of
Arizona. Two extinct Pleistocene species of the subgenus (Corynorhinus) are
also recognized: P. alleganiensis from Cumberland cave in Maryland and P.
tetralophodon from San Josecito Cave in Mexico (Handley 1959). Handley (1959)
lists no characters to distinguish the dentaries of different species of
Plecotus, but the bats living in the cave are clearly P. townsendii.
Lack of positive evidence for this species in the Crystal Ball Cave
assemblage could represent lack of chance preservation or a recent change in
the species that inhabit the cave. Since the assemblage contains
indistinguishable Pleistocene and Recent specimens, even if the lower jaws
could be identified as Plecotus they would not reveal how long this species
has inhabited the cave. Humphrey and Kunz (1976) postulated that mild winters
during the late Pleistocene allowed P. townsendii to roost in trees rather
than caves and to avoid the present habit of long winter hibernation, whereas
this bat now use caves as refugia to survive the intolerably cold
post-Pleistocene winters. Humphrey and Kunz (1976) cited evidence that this
bat is very sedentary and now survives only in isolated areas where suitable
winter hibernacles are available. Handley (1959) stated that very few
specimens of Plecotus townsendii have been reported considering its large
geographic range. Durrant et al. (1955) said this species was thought to only
inhabit the southern half of Utah until a few isolated citings were made in
northern Utah caves, one of which (in Logan Canyon) contained the bat in
large numbers. It is, therefore, very possible that P. townsendii has not
inhabited Crystal Ball Cave, at least to the large degree that it does now,
until Recent times.
Material--Anterior portion of left maxilla with C1/, P4/ (BYUVP 5365),
anterior portion of fused dentary pair with left P/4, M/1 (BYUVP 5351),
posterior portion of right dentary with M/2 (BYUVP 5333), posterior portion
of left dentary with M/1 (BYUVP 5334). A posterior fragment of a left dentary
(BYUVP 5350) and a right M/2 (BYUVP 5335) probably also belong to this taxon
based on their large size and chiropteran affinities.
Discussion--This is the largest species of bat found in the assemblage and is
easily distinguishable from other vespertilionids by its unique tooth formula
of I1/2, C1/1, P1/2, M3/3, the configuration of the incisors and fenestra in
the anterior palate, and the high coronoid process on the dentary. A.
pallidus has not been reported living in the cave, but it presently occurs
from the region of the cave southward into Mexico and along the west coast of
the United States and southern British Columbia. A. bunkeri is now considered
a subspecies of A. pallidus (Hall 1981). A. dubiaquercus occurs in Mexico and
Central America and is distinguished from A. pallidus by normally having 3
lower incisors instead of 2. A. koopmani occurs only in Cuba. All the
material listed above matches perfectly with modern A. pallidus which lives
in the region of Crystal Ball Cave.
Material--Anterior portion of skull with all teeth (BYUVP 5387), right
maxilla with M/1,/2 (BYUVP 5407), right maxilla with M/2 (BYUVP 5406), right
maxilla without teeth (BYUVP 5385), anterior portion of right maxilla with
M/1 (BYUVP 5404), 2 anterior portions of right maxillae without teeth (BYUVP
5386, 5405), 4 partial right maxillae without teeth (BYUVP 5368, 5409, 5410,
5412), 6 left maxillae without teeth (BYUVP 5381, 5383, 5384, 5396, 5397,
5417), 3 anterior portions of left maxillae without teeth (BYUVP 5374-5376),
5 partial left maxillae without teeth (BYUVP 5369, 5382, 5408, 5415, 5416),
right dentary with P/4, M/2,/3 (BYUVP 5399), right dentary with M/2,/3 (BYUVP
5393), right dentary with M/2 (BYUVP 5395), 5 right dentaries without teeth
(BYUVP 5390-5392, 5401, 5419), partial right dentary with P/4 (BYUVP 5370),
4 partial right dentaries without teeth (BYUVP 5367, 5411, 5413, 5414), 2
anterior portions of right dentaries without teeth (BYUVP 5371, 5372), left
dentary with P/4, M/1,/2 (BYUVP 5402), left dentary with M/1,/2 (BYUVP 5398),
3 left dentaries without teeth (BYUVP 5394, 5403, 5418), anterior portion of
left dentary with P/4, M/1,/2,/3 (BYUVP 5388), posterior portion of left
dentary with M/1,/2,/3 (BYUVP 5389), 2 posterior portions of left dentaries
without teeth (BYUVP 5377, 5400), partial left dentary with M/1,/2 (BYUVP
5378), 3 partial left dentaries without teeth (BYUVP 5373, 5379, 5380).
Discussion--Ochotonids are easily distinguished from leporids by the lingual
curve in the maxilla behind the cheek teeth, the presence of 5 upper cheek
teeth rather than 6, and M/3 and its socket being anteroposteriorly short
instead of triangular. O. princeps presently inhabits high elevations within
120 miles (190 km) of Crystal Ball Cave, both to the east and west (Hall
1981). The only other extant species, O. collaris, occurs only in
northwestern Canada and Alaska (Hall 1981) and has been found in fossil
deposits only in that region (Kurten and Anderson 1980). The only known
extinct North American species of Ochotona is O. whartoni, which is known
only from the early Pleistocene and is distinctly larger than the extant
species (Kurten and Anderson 1980). All the specimens listed above are
indistinguishable from Recent O. princeps.
Why O. princeps has been extirpated from the Snake Range is uncertain, but
fossils have been recovered from Smith Creek Cave (Miller 1979) and many
other Great Basin localities where this species does not live today. For
example, Grayson (1977) recovered O. princeps dated at 7,000 to 12,000 Y.B.P.
from the Fort Rock Basin of south-central Oregon. The area is now dominated
by sagebrush, grasses, and sparse junipers, but modern pikas in the region
only live where there is more succulant vegetation. Grayson (1977) attributed
the disappearance of Ochotona to either a shift to more xeric habitat or to
an eruption of Mt. Mazama 7,000 years ago. A similar extirpation in the Snake
Range 315 miles (500 km) to the southeast supports the former of Grayson's
hypotheses.
Material--Right dentary with P/4, M/1,/2 (BYUVP 5534), right dentary without
teeth (BYUVP 5444), right dentary fragment with P/3 (BYUVP 5584), left
dentary with P/3,/4, M/1 (BYUVP 5536), left dentary fragment without teeth
(BYUVP 5434).
Discussion--S. idahoensis is distinguished from all other leporids by its
small size (see figure 4) and from Ochotona by the characters listed above.
The P3/ of S. idahoensis does not widen posteriorly, as in other species of
Sylvilagus, and the second reentrant angle is not crenulated as it is in many
leporids. BYUVP 5536 is larger than any of the Recent S. idahoensis specimens
to which it was compared (but smaller and distinct from other species of
leporids), and the other specimens are also comparatively large, suggesting
that this species may have decreased in size at the end of the Pleistocene.
This species presently occurs in the region of the cave and to the north and
west (Hall 1951, 1981).
Material--Anterior portion of right dentary without teeth (BYUVP 5493), left
dentary with M/1 (LACM 123658), anterior portion of left dentary with I/1,
P/3,/4, M/1 (BYUVP 5578), four right P/3's (BYUVP 5717, 5731, 5769, and
5794), four left P/3's (BYUVP 5773, 5782, 5795, 5810).
Discussion--Sylvilagus is commonly distinguished from Lepus by its smaller
size, although there is some overlap (namely, S. aquaticus and S.
cunicularius are larger than L. americanus; J. A. White 1984 personal
communication). The species of these genera presently living in the region
are usually discernible by size, but the species within each genus are
usually not (see figure 4).
Of the two species of Sylvilagus presently living in the Snake Range, S.
audubonii has a larger mean size and tends to have much more crenulation in
the second reentrant angle of P/3 than S. nuttallii (although there is
overlap in both characters). S. floridanus, which occurs just south of Utah
and Nevada, has an even larger mean size than S. audubonii but has little
crenulation in the P/3 like S. nuttallii. BYUVP 5493 and LACM 123658 compare
well in size with S. nuttallii and S. audubonii (see figure 4), but none of
the nine P/3's of Sylvilagus size have much crenulation in the second
reentrant angle of P/3, suggesting that they belong to S. nuttallii rather
than S. audubonii. Although other species could be represented, the evidence
suggests that at least the majority of the specimens listed above are of S.
nuttallii.
S. nuttallii presently inhabits the region of the cave and northward, whereas
S. audubonii inhabits the region of the cave and southward. S. nuttallii also
tends to occur at higher elevations and in more wooded or bushy areas than S.
audubonii, which lives in plains or open country (Hall 1951). Since Gandy
Mountain is presently covered with only sparse bushes and is surrounded by
open plains, the presence of S. nuttallii and absence of S. audubonii
suggests the replacement of woodland-alpine vegetation by the present desert
conditions since the Pleistocene.
Material--Right dentary with I/1, P/3,/4, M/1,/2 (BYUVP 5519), anterior
portion of left dentary with P/4, M/1 (BYUVP 5543). A left dentary with /I
(BYUVP 5430) falls within the size range of L. americanus and L.
californicus.
Discussion--The jaw dimensions and P/3 widths of these specimens are
intermediate in size between the Sylvilagus specimens (described above) and
the majority of the Lepus specimens (described below). They fall in and near
the range of variation of the smallest L. californicus and largest S.
audubonii specimens (see figure 4), but most of the P/3's of these two
species have a highly crenulated second reentrant angle whereas the P/3 of
BYUVP 5519 does not. These specimens are also indistinguishable from S.
floridanus, but this species has never been reported living or as a fossil
from Utah or Nevada.
L. americanus does not presently occur in the Snake Range but does occur 100
miles (160 km) to the north and east, mainly at high elevations (Durrant
1952, Hall 1951). Since the assemblage generally contains more species that
presently range north of the cave than south of the cave, it is not at all
unreasonable that L. americanus could have inhabited the region of the cave
in the recent geologic past. Kurten and Anderson (1980) listed a number of
fossil sites where L. americanus has been found south of its present
range.
Material--Fused dentary pair with right P/3,/4, M/1,/2,/3, left I/, P/3,/4,
M/1,/2 (BYUVP 5488), right dentary with M/1,/2 (BYUVP 5467), right dentary
with I (BYUVP 5533), left dentary with all teeth (BYUVP 5442), left dentary
with I, P/3,/4, M/1,/2 (BYUVP 5484), 5 left dentaries without teeth (BYUVP
5424, 5429, 5474, 5532, LACM 123657), anterior portion of left dentary
without teeth (BYUVP 5439), 7 isolated right P/3's (BYUVP 5733, 5770-5772,
5793, 5796, 5802), 7 isolated left P/3's (BYUVP 5735, 5736, 5780, 5783, 5790,
5791, 5804). A partial left dentary with P/3 (BYUVP 5485), 28 dentaries
lacking P/3 (BYUVP 5422, 5427, 5436, 5438, 5448, 5450, 5454, 5456, 5458,
5462, 5473, 5475, 5478, 5483, 5487, 5489, 5493, 5495, 5500-5502, 5524, 5527,
5530, 5531, 5540-5542), 7 isolated right P/3's (BYUVP 5617, 5732, 5745, 5768,
5774, 5778, 5792), and 5 isolated left P/3's (BYUVP 5716, 5775, 5776, 5801,
5809) show characteristics common to both L. townsendii and L.
californicus.
Discussion--L. townsendii and L. californicus are distinguished from
Sylvilagus and L. americanus by their large size. They are distinguished from
each other by L. townsendii having a larger mean size (see figure 4) and
having less crenulation in the second reentrant angle of P/3 than L.
californicus (Hibbard 1952). Miller (1976) observed L. californicus to have
a highly crenulated P/3 in most, but not all, cases, and Hibbard (1944, 1963)
noted that individual variation is very great. My observations and those of
J. A. White (1984 personal communication) show that many individuals of these
species cannot be distinguished by either size or the amount of crenulation
in P/3. But statistical analysis can be used to estimate their relative
abundance (Grayson 1977). Hibbard (1952) stated that the anterior part of P/3
is narrower in L. townsendii than in L. californicus, but although I noticed
variation in the narrowness and roundedness of the anterior P/3's, it did not
correlate with the amount of crenulation in the second reentrant angle of
that tooth. BYUVP 5424, 5467, and 5474 have greater alveolar length (P/3-M/3)
to diastema length ratios than any Recent leporid specimens measured (see
figure 4), but they fall closest in size, especially based on their long
tooth row length, to L. townsendii.
Since 11 of the 43 measurable Lepus dentaries are larger than any modern L.
californicus specimens measured (see figure 4) and over half of the large
Lepus P/3's from the assemblage show no crenulation (a very rare condition in
L. californicus), it is clear that L. townsendii is well represented. Most of
the 29 jaws that could be either L. townsendii or L. californicus are closer
to the mean size of L. townsendii, and the isolated 13 P/3's of L. townsendii
or L. californicus have slight crenulation in the second reentrant angle yet
are considerably less crenulated than the vast majority of L. californicus
specimens. Since only two highly crenulated P/3's clearly belonging to L.
californicus (listed below) were found, most of these 13 P/3's with
intermediate crenulation probably belong to L. townsendii. Based on this
information I estimate that the ratio of L. townsendii to L. californicus
specimens from the Crystal Ball Cave assemblage is about ten to one.
Grayson (1977) stated that L. townsendii is a more northern species and
inhabits higher elevations and more grassy habitats than L. californicus,
which prefers dryer shrubby areas. With Sylvilagus, the more northern species
is represented in the assemblage while the more southern species is not. This
is also the trend with Lepus. Hall (1981) reported L. townsendii in the area
of Crystal Ball Cave but Durrant (1952), in a more detailed map, did not.
Both report L. californicus throughout the Bonneville Basin area. I have seen
numerous L. californicus around Gandy but never a L. townsendii, and J. C.
Bates (1984 personal communication) reported never noticing any L. townsendii
but numerous L. californicus. This difference between the fossil and living
species at Gandy suggests that climatic boundaries have shifted upward in
latitude and elevation since the Pleistocene. Grayson (1977), using both
fossil and Recent data, demonstrated that L. californicus increased in number
at the expense of L. townsendii during the Recent, and that it became the
more dominant species in the Great Basin 5,000 to 7,000 years ago. Although
the ecological and adaptational differences between these two species are not
fully understood, Grayson (1977) attributed this change to a post-Pleistocene
warming trend. The species shift indicated by the Crystal Ball Cave
assemblage reiterates the data presented by Grayson (1977).
Material--Right P/3 (BYUVP 5781), left P/3 (BYUVP 5734). Twenty-nine
dentaries and 13 other P/3's (listed under L. townsendii) show characters
found in both L. townsendii and L. californicus. A left dentary with /I
(BYUVP 5430) falls within the size range of L. americanus and L.
californicus.
Discussion--L. californicus differs from L. townsendii in having a smaller
mean size (see figure 4) and a more crenulated second reentrant angle in P/3
as discussed above. The two P/3 specimens listed above have more crenulation
than was seen in eight Recent L. townsendii specimens but are typical of L.
californicus. The 13 P/3's of either L. townsendii or L. californicus (listed
and discussed above) show less crenulation than the vast majority of L.
californicus specimens studied, but some of them could represent L.
californicus since crenulation in the P/3 is not always present (Miller
1976). L. californicus is presently the most common lagomorph around Crystal
Ball Cave (J. C. Bates 1983 personal communication), so its poor
representation in the fossil assemblage suggests that it has only recently
become abundant there.
Material-Anterior portion of skull with right M1/,2/,3/, left M1/,3/ (BYUVP
6528), anterior portion of skull without teeth (LACM 123663), dentary pair
with right M/1,/3 (BYUVP 6536), right dentary with P/4, M/1,/3 (LACM 123665),
right dentary with M/1,/2,/3 (BYUVP 6543), right dentary with M/2,/3 (BYUVP
6621), right dentary with M/3 (BYUVP 6620), left dentary with /I, M/1,/2,/3
(BYUVP 6477), left dentary with M/1,/2,/3 (LACM 123669). Another 70 partial
maxillae (some with teeth), 70 partial dentaries (some with teeth), and
approximately 300 isolated cheek teeth (BYUVP 6476, 6478-6518, 6520-6527,
6529-6535, 6537-6542, 6544-6605, 6607-6619, 6622-6648, LACM 123664,
123666-123668, 123670) are of Marmota and compare favorably with M.
flaviventris.
Discussion--Marmota is distinctly larger than other living sciurids (Hall
1981) but distinctly smaller than the extinct Paenemarmota (Repenning 1962).
M. flaviventris is distinguished from M. monax by its anteriorly divergent
upper tooth rows and from M. caligata, M. olympus, and M. vancouverensis by
its smaller size (Hall 1981). M. flaviventris is also distinguished from
these other species by its less massive dentition, M3/ being longer than
wide, and M/3 having a triangular rather than a quadrangular outline (Logan
1983). Hay (1921) named M. arizonae based on a partial skull from northern
Arizona and said it was similar to M. flaviventris. Since the specimen is
probably late Pliocene in age and the validity of the species is uncertain
(Kurten and Anderson 1980), it is not considered a candidate for the Crystal
Ball Cave specimens, all of which are indistinguishable from Recent M.
flaviventris.
The presence of M. flaviventris in the Crystal Ball Cave assemblage
represents a shift in the climate and vegetation of the area because this
species now inhabits only much higher elevations in the Snake Range (Hall
1981, Mead et al. 1982) and does not live on or around Gandy Mountain (J. C.
Bates 1983 personal communication). Hall (1946) reported fossil M.
flaviventris from several caves far south of this species' present range.
Zimina and Gerasimov (1969) proposed that the marmot greatly expanded its
distribution and numbers under late Pleistocene periglacial conditions for
which it was well adapted but has since diminished significantly. M.
flaviventris is not a cave-dwelling species, so its great abundance in the
Crystal Ball Cave assemblage suggests that it once lived on Gandy Mountain in
large numbers, strongly supporting the hypothesis of Zimina and Gerasimov
(1969).
Material--Anterior portion of skull with both I/'s (BYUVP 6060), partial
skull with right P4/, M1/,2/ (BYUVP 6255), partial skull without teeth (BYUVP
6462), 7 right dentaries with all teeth (BYUVP 6107, 6109, 6141, 6282, 6284,
6326, 7256), and 2 left dentaries with all teeth (BYUVP 6421, 6433). Another
439 partial maxillae (some with teeth), 562 partial dentaries (some with
teeth), and approximately 4,000 isolated teeth compare favorably with S.
townsendii.
Discussion--Spermophilus townsendii has the smallest mean size of any North
American species of Spermophilus and is also slightly smaller than
Ammospermophilus leucurus (Hall 1981). Spermophilus also differs from
Ammospermophilus by having distinctly larger masseteric tubercles just
anterior to the upper tooth rows (Hall 1981). The three partial skulls listed
above and many of the partial maxillae without teeth have large masseteric
tubercles that distinguish them from Ammospermophilus. All of the specimens
listed above compare best in size with S. townsendii, but some of those only
referred to this species are probably Ammospermophilus. Kurten and Anderson
(1980) listed 13 extinct species of Spermophilus, but the only one close
enough in size and age of deposits to the Crystal Ball Cave specimens to be
considered is S. taylori, named by Hay (1921) based on a single specimen from
Texas. Kurten and Anderson (1980) consider this a doubtful species, and it is
most likely a synonym of S. townsendii, so it is not considered here.
The presence of a single species of Spermophilus at Crystal Ball Cave is a
striking contrast to the five possible species recovered from Smith Creek
Cave in subequal numbers (Mead et al. 1982). These include S. cf. townsendii,
S. variegatus, and S. cf. lateralis, which still inhabit the Snake Range, and
S. cf. richardsonii and S. cf. beldingi, which have been extirpated but still
inhabit Utah and/or Nevada (Hall 1981). The reason for this difference may be
that Smith Creek Cave is at the base of 12,050 foot (3,673 meter) Mount
Moriah and at the edge of the flat open Snake Valley, an area of diverse
niches in contact with several diverse environments even now, and certainly
an area across which climatic boundaries crossed many times during the
Pleistocene. Gandy Mountain, on the other hand, is only a small hill far out
in Snake Valley, the area most favorable to S. townsendii (Hall 1946), and is
isolated from the main Snake Range by 6 miles (10 km) of flat valley.
The abundance of Spermophilus townsendii fossils at Crystal Ball Cave
suggests that this squirrel lived around Gandy Mountain in large numbers for
a long time, probably since fossils started accumulating in the cave. Durrant
(1952) said this species is well-suited to the western Utah desert and is
particularly abundant around springs. Hall (1946) told how S. townsendii was
a traditional food for native American Indians. S. townsendii is not a
cave-dwelling animal as is Neotoma, and yet it is over twice as abundant as
Neotoma in the assemblage (contrary to my earlier statement that Neotoma was
the best represented genus, Heaton 1984). Neotoma has a much more restricted
niche than Spermophilus and is never found in large numbers. Since squirrels
are very unlikely to venture deep into caves, all the specimens must have
been brought in by wood rats and/or small carnivores. It is interesting that
fossil deposition occurred so rapidly, even deep in this isolated cave, that
an outside species is better represented than the primary cave-dwelling
species. J. C. Bates (1984 personal communication) reported seeing no
squirrels on Gandy Mountain and only a few in the surrounding valley in the
many years he has lived in Gandy. This, in contrast to its abundance as a
fossil, suggests that S. townsendii reduced its numbers at the close of the
Pleistocene.
Material--Right maxilla without teeth (BYUVP 8295), 2 left maxillae without
teeth (BYUVP 8296, 8297). Some of the 439 maxillae, 562 dentaries, and
approximately 4,000 isolated teeth listed under Spermophilus townsendii
probably also belong to this taxon.
Discussion--Ammospermophilus is distinguished from Spermophilus by its
smaller masseteric tubercle and its less robust lower cheek teeth (Hall
1981). A. leucurus now lives around Gandy Mountain while A. harrisii, A.
interpres, A. insularis, and A. nelsoni, the other four extant species, occur
only south of Utah (Hall 1981), so the Crystal Ball Cave specimens are
referred to A. leucurus although no character could be found to rule the
others out.
According to Durrant (1952) A. leucurus commonly occurs with S. townsendii
but has a more restricted habitat, preferring rocky terrains.
Ammospermophilus is best adapted for high temperatures (Vaughan 1972), and
its low abundance in the assemblage compared to Spermophilus townsendii
suggests that it has not inhabited the area as long, at least not in its
present abundance. With summers becoming hotter and drier at the close of the
Pleistocene, Ammospermophilus may have increased its numbers at the expense
of other species in Recent times.
Discussion--Eutamius has two premolars in each maxilla whereas Tamius has
only one. E. minimus is the smallest species of Eutamius and has a narrower
and squarer P/4 than E. dorsalis or E. umbrinus. All the specimens listed
above match E. minimus with respect to the P/4 and are smaller than the other
species. E. minimus and E. dorsalis live in the region of Crystal Ball Cave
and E. umbrinus lives higher in the Snake Range and westward into Nevada
(Hall 1981). E. minimus was also recovered from Smith Creek Cave (Mead et al.
1982). E. minimus inhabits diverse habitats from deserts to forests, so its
presence in the assemblage is not surprising.
Material--Right dentary with P/4, M/1,/2,/3 (BYUVP 6233), right dentary with
P/4, M/1 (BYUVP 6257), 2 right dentaries with M/1 (BYUVP 5974, 6304), 2 left
dentaries with M/1 (BYUVP 6129, 6134). Three partial right maxillae with M1/
(BYUVP 6064, 6288, 6295) and a partial left maxilla with M1/ (BYUVP 6000)
also compare favorably with this species.
Discussion--E. dorsalis is distinctly larger than E. minimus and slightly
larger than E. umbrinus (Mead et al. 1982). It has a distinct isolated
mesoconid on M/1 that is lacking in E. umbrinus and is part of an ectolophid
in E. minimus (Miller 1976). The M/1's of the six dentaries listed above
match E. dorsalis in this character, and the four maxillae listed above match
best in size with E. dorsalis but cannot be positively distinguished from E.
umbrinus. Of the larger chipmunks, only E. cf. umbrinus was reported from
Smith Creek Cave (Mead et al. 1982), and I have found only E. dorsalis in
Crystal Ball Cave. Their present ranges may account for this difference since
E. umbrinus only inhabits the Snake Range west of Crystal Ball Cave while E.
dorsalis inhabits the entire range (Hall 1981). Their ranges show that E.
umbrinus is more isolated in areas of high elevation and more commonly absent
from the areas once covered by Lake Bonneville.
Material--Anterior portion of skull with both I/'s (BYUVP 6656), anterior
portion of skull with left I/ (LACM 123672), right dentary with /I, P/4, M/1
(BYUVP 6657), left dentary with P/4 (BYUVP 8283). Four palates without teeth
(BYUVP 6653-6654, 6664-6665), 4 right dentaries without cheek teeth (BYUVP
6660, 6663, 6666, 8281), and 8 left dentaries without cheek teeth (BYUVP
6655, 6658-6659, 6662, 6681, 7009-7010, 8282) also compare favorably with
this species.
Discussion--Thomomys is distinguished from other North American geomyids by
the absence of a superficial groove on the anterior face of the upper
incisors (illustrations in Hall 1981), and none of the I/'s listed above have
this groove. T. umbrinus differs from T. talpoides and T. monticola, the only
other species of Thomomys living in Nevada, Utah, or surrounding areas, by
having a sphenoidal fissure, by not having the palatine foramina fully
anterior to the anterior openings of the infraorbital canals (Durrant 1952),
and by the absence of a lingual indentation in the anterior lobe of P/4 (Hall
1946). The two Thomomys skulls from Crystal Ball Cave have the sphenoidal
fissure, and their palatine foramina are fully anterior to the infraorbital
canals. The two P/4's also lack the lingual indentation as in T. umbrinus. My
observations and also figures 308-321 in Hall (1946) indicate that T.
umbrinus has a larger mean size than the other two species mentioned
(contrary to Bergman's rule), and all the Crystal Ball Cave specimens compare
best in size with the larger T. umbrinus.
T. umbrinus is the only geomyid currently inhabiting the Snake Range, and it
is a southern species extending from Nevada and Utah southward into Mexico
(Hall 1981). T. bottae and T. townsendii are now considered as subspecies of
T. umbrinus (Hall 1981). T. talpoides, which inhabits mountain ranges to the
east and west of the Snake Range, has Nevada and Utah as almost its southern
boundary and extends northward into Canada. T. talpoides tends to inhabit
higher elevations than T. umbrinus as well as higher latitudes. T. cf.
talpoides is the only geomyid reported from Smith Creek Cave (Goodrich
1965).
Hall (1946) pointed out that although T. umbrinus is usually a lower
elevation species than T. talpoides, T. umbrinus is the only geomyid in the
Snake Range and occurs at all elevations (but is less abundant at higher
elevations than T. talpoides is at similar elevations in other ranges). Hall
(1946) attributed this to antiquity of occupancy and proposed that T.
umbrinus, having no competitors in the Snake Range, developed populations
adapted to higher elevations. Since T. umbrinus was the species best adapted
to the valleys surrounding the Snake Range, no species which were better
adapted to higher elevations could pass through to their favorable habitat.
This could explain why the Crystal Ball Cave assemblage suggests no northward
range shift for species of Thomomys as it does for other groups such as
lagomorphs. If Hall (1946) is right, the tentative assignment of the Smith
Creek Cave specimen to T. talpoides (Goodrich 1965) must be in error. Another
possibility is that predatory birds transported the specimen to the cave, but
this seems unlikely since T. talpoides occurs only as close as 45 miles (75
km) to the northwest and 108 miles (180 km) to the east of Smith Creek Cave.
Hall (1946) also pointed out that geomyids, as individuals, are extremely
sedentary, and this could be the cause of their slow invasion and northward
retreat compared to other mammals.
Material--Partial right maxilla with P4/ (BYUVP 6682), 2 right dentaries with
P/4 (BYUVP 6859, 6879), 2 right dentaries with M/2 (BYUVP 6711, 6856), left
dentary with all teeth (BYUVP 6697), left dentary with P/4, M/1 (BYUVP 6786),
left dentary with P/4, M/2 (BYUVP 6115).
Discussion--P. longimembris, P. parvus, and P. formosus now inhabit the
Crystal Ball Cave area, and the closest other species range more than 150
miles (250 km) to the east and south (Hall 1981). Of the three local species,
P. longimembris can be ruled out because its M/3 is distinctly smaller than
its P/4 (Hall 1981), and BYUVP 6697 has the opposite condition. P. parvus and
P. formosus are very similar dentally, and the Crystal Ball Cave specimens
match well with both of them. P. formosus has a larger mean size than P.
parvus, and the Crystal Ball Cave specimens compare best in size with P.
formosus although P. parvus and several other western species cannot be ruled
out. Miller (1979) referred all the Perognathus specimens found at Smith
Creek Cave to P. cf. parvus, but since the identification was tentative at
both caves, it does not seem wise to speculate about a possible difference
between the two assemblages.
Material--Right maxilla with P4/, M1/,2/ (BYUVP 6695), right maxilla with
P4/, M2/ (BYUVP 6781), right maxilla with M1/ (BYUVP 6709). Three partial
right maxillae with P4/ (BYUVP 6669, 6674, 6797), a partial right maxilla
with a partial M1/ (BYUVP 6759), a right dentary with /I, P/4, M/1 (BYUVP
6693), 2 right dentaries with P/4 (BYUVP 6795, 6860), and a left dentary with
P/4 (BYUVP 6708) are of Microdipodops and compare favorably with M.
megacephalus.
Discussion--Microdipodops is most similar to Perognathus but can be
distinguished dentally by the molars having a single enamel loop as opposed
to the biloph nature of Perognathus molars. The P/4's are also distinct in
being more hypsodont and having a straight posterolabial border as opposed to
the round and symmetrical nature of the Perognathus P/4's. M. megacephalus
ranges throughout most of Nevada and into neighboring states including Utah,
and it is currently found around Crystal Ball Cave (Hall 1981). M. pallidus,
the only other species, occurs along the southern Nevada-California border
more than 200 miles (320 km) southwest of Crystal Ball Cave (Hall 1981). M.
megacephalus can be distinguished from M. pallidus by the latter possessing
a small notch in the labial side of M1/, and all the Crystal Ball Cave
specimens possessing the M1/ are clearly M. megacephalus. M. cf. megacephalus
was reported at Smith Creek Cave (Miller 1979), and all heteromyid taxa
recovered were low in abundance as at Crystal Ball Cave. This low abundance
is probably due to a low density in life since even now they are rarely seen
in the area.
Material--Two right dentaries with /I (BYUVP 6672 and 8284), left dentary
fragment with P/4 (BYUVP 6676). Nine maxillae without teeth (BYUVP 5593,
6667-6668, 6670, 6675, 6677-6680) and 2 right dentaries without teeth (BYUVP
6673, 6683) also compare favorably with this taxon.
Discussion--Dipodomys is distinctly larger than other heteromyid genera. D.
microps is distinguished from other species of Dipodomys by having
chisel-shaped lower incisors (anterior face flat) rather than awl-shaped
lower incisors (anterior surface round), and the incisors of BYUVP 6672 and
8284 are chisel-shaped. P/4 is also distinct in having a larger and more
isolated anterior loph than D. ordii or D. merriami but not a complete
separation of lophs as in D. deserti, and the P/4 of BYUVP 6676 clearly
matches D. microps. The referred specimens also match perfectly with Recent
D. microps, but lack the diagnostic teeth. Of the four species of Dipodomys
presently living in Utah and Nevada, D. microps and D. ordii are found in the
Snake Range while D. merriami and D. deserti occur more than 125 miles (200
km) to the south and west (Hall 1981). D. microps has a much smaller range
than D. ordii, occurring only in Nevada and parts of surrounding states (Hall
1981). The Dipodomys specimens recovered from Smith Creek Cave (Miller 1979)
were referred to D. ordii because they had awl-shaped lower incisors. This
difference between the two assemblages is difficult to explain because the
range differences between these species do not suggest distinct differences
in habitat preference.
Material--Right maxilla fragment with M1/,2/ (BYUVP 6703), left maxilla with
M1/,2/,3/ (BYUVP 6782), left maxilla fragment with M1/,2/ (BYUVP 6771).
Thirty nine Peromyscus dentaries containing one or more molars compare
favorably with P. maniculatus and P. crinitus.
Discussion--Of the six species of Peromyscus that inhabit Utah and Nevada,
only P. maniculatus, P. truei, and P. crinitus currently live around Crystal
Ball Cave (Hall 1981). P. maniculatus was captured live inside the cave by
the author in 1982 and 1983. Peromyscus fossils from Smith Creek Cave were
not identified to the species level (Goodrich 1965, Mead et al. 1982, Miller
1979). Dental characters which distinguish species of Peromyscus are few and
not always reliable. P. maniculatus and P. truei belong to the subgenus
Peromyscus, which has accessory tubercles or enamel loops on the labial side
of M1/ and M2/; P. crinitus belongs to the subgenus Haplomyomys which lacks
these features (Hall 1981). I found this character to be quite reliable, and
the specimens listed above all have prominent cusps on M1/ and M2/. In
further refinement of this character, Miller (1971, 1976) was able to
separate P. maniculatus from all other western species of Peromyscus by the
presence of an anteroconule on M1/ with direct attachment to the anterocone
rather than being joined to it by a distinct loph as in P. truei. Specimens
listed above fit P. maniculatus in this respect. Species of the subgenus
Haplomyomys usually lack the anteroconule entirely (Hall 1981, Miller 1971,
1976). Unfortunately, excessive wear on the teeth erases this character.
Of the 40 Peromyscus dentaries containing one or more molars, 39 compare best
in size with the smaller P. maniculatus and P. crinitus, but no character
could be found to separate these species based on dentaries. Miller (1976)
found the P/3's of P. maniculatus, P. crinitus, and P. eremicus to be
relatively more reduced than P. boylii and P. truei. The 8 Crystal Ball Cave
Peromyscus dentaries containing M/3 tend to have M/3 relatively reduced as in
P. maniculatus, P. crinitus, and P. eremicus, and in size all the 39
dentaries listed above compare best in size with the smaller P. maniculatus
and P. crinitus.
Material--Right maxilla with M1/,2/ (BYUVP 6780), left maxilla with M1/,2/
(BYUVP 6769), left maxilla with M1/ (BYUVP 6715). Thirty nine Peromyscus
dentaries containing one or more molars compare favorably with P. maniculatus
and P. crinitus.
Discussion--These specimens lack accessory tubercles and enamel loops on the
2 principle outer angles of M1/ and M2/, so they probably belong to the
subgenus Haplomyomys (Hall 1981). Of the two species of Haplomyomys found in
Utah, P. crinitus and P. eremicus, the Crystal Ball Cave specimens compare
better in size with the smaller P. crinitus (although there is considerable
overlap). Some of the 39 dentaries discussed under P. maniculatus (above)
could also belong to this species since no character was found to distinguish
them based on dentaries. P. crinitus is presently found around the cave while
P. eremicus only ranges as close as 135 miles (225 km) to the south (Hall
1981), and this further suggests that these specimens are P. crinitus.
Material--Left dentary with M/1 (BYUVP 6718).
Discussion--P. truei is the largest species of Peromyscus living in Utah and
Nevada (Durrant 1952, Hall 1981), and the M/1 listed above compares well in
size with this species and is larger than the mean size of P. eremicus and P.
boylii and distinctly larger than any P. maniculatus or P. crinitus M/1's
examined. Identification is based only on size since no other character could
be found to distinguish M/1's of Peromyscus. This species is found throughout
the Great Basin, so its presence in the assemblage is not surprising.
Material--Partial skull without teeth (LACM 123671), 2 partial right maxillae
with M1/ (BYUVP 7045, 7065), 2 left maxillae with M1/ (BYUVP 7154), partial
left maxilla with M1/ (BYUVP 7246).
Discussion--N. lepida and N. cinerea are the only species of Neotoma that
presently inhabit the Snake Range (Hall 1946, 1981). Of three wood rats that
I trapped in Crystal Ball Cave and two elsewhere on Gandy Mountain in 1982
and 1983, all were N. lepida. I did trap a N. cinerea in another cave in the
Snake Range 22 miles (35 km) south of Crystal Ball Cave, so they are known to
inhabit caves in the area. Miller (1979) reported both N. lepida and N.
cinerea from Smith Creek Cave but did not comment on their relative
abundance. Of these two species, N. cinerea is much more boreal than N.
lepida, having a more northern range and being found at higher elevations
(Finley 1958, Hall 1946, 1981). Durrant (1952) and Hall (1981) also reported
N. albigula, N. mexicana, and N. stephensi living in Utah but far south and
east of Crystal Ball Cave.
Neotoma cinerea is usually distinguishable from N. lepida by its larger size
and deeper anterolabial reentrant angle on M1/ (Finley 1958). According to
Hall (1946), the maxillary alveolar length is always 8.8 mm or less in N.
lepida and 9.1 mm or more in N. cinerea for the Nevada subspecies, and Finley
(1958) reported only a slight overlap for the Colorado subspecies. The three
other Utah species of Neotoma are intermediate in size between N. lepida and
N. cinerea, and N. albigula has the M1/ pattern of N. lepida while N.
mexicana and N. stephensi have the M1/ pattern of N. cinerea (Finley 1958).
Because these are the most diagnostic characters, only maxillae with M1/
and/or a measurable alveolar length were considered.
The Crystal Ball Cave specimens listed above compare best in size with N.
lepida, the only species of Neotoma known to presently inhabit the cave.
Maxillary alveolar lengths of Neotoma specimens from the cave show a strongly
bimodal distribution, suggesting that N. albigula, N. mexicana, and N.
stephensi are not represented since they are intermediate in size between N.
lepida and N. cinerea. The shallow anterolabial reentrant angle of the M1/'s
also compares favorably with N. lepida. The scarcity of N. lepida specimens
in the assemblage suggests that this species probably has not always
inhabited the cave as it does now.
Material--Anterior portion of skull with both I/, M1/,2/ (BYUVP 7384),
maxilla pair with all teeth except left I/ (BYUVP 7281), maxilla pair with
right M1/,2/,3/, left M1/,2/ (BYUVP 7282), maxilla pair with both M1/,2/
(BYUVP 7067), maxilla pair with right M/1,/2 (BYUVP 7015), maxilla pair with
left M/1 (BYUVP 7213), 9 right maxillae with M1/,2/,3/ (BYUVP 7136, 7149,
7158, 7167, 7214, 7248, 7254, 7314, 7320), 3 right maxillae with M1/ (BYUVP
7273, 7316, 7330), 25 partial right maxillae with M1/ (BYUVP 7014, 7018,
7024, 7038, 7046, 7104, 7114, 7125, 7134, 7138, 7147, 7170, 7177, 7180, 7182,
7197, 7204, 7216, 7242, 7247, 7249, 7276, 7344, 7348, 7349), 10 right
maxillae without teeth (BYUVP 7255, 7343, 7353, 7367, 7377, 8286-8290), 7
left maxillae with M1/,2/,3/ (BYUVP 7095, 7212, 7250, 7257, 7274, 7376,
7379), 4 partial left maxillae with M1/,2/ (BYUVP 7101, 7174, 7179, 7324),
partial left maxilla with M1/,2/ (BYUVP 7017), 34 partial left maxillae with
M1/ (BYUVP 7021, 7061, 7062, 7072, 7073, 7087, 7099, 7106, 7133, 7140, 7142,
7144, 7145, 7151, 7162-7164, 7172, 7175, 7183, 7189, 7200, 7205, 7217, 7220,
7225, 7267, 7300, 7317, 7318, 7322, 7351, 7362, 7371), 6 left maxillae
without teeth (BYUVP 7171, 7346, 8291-8294). Another approximately 200
maxillae, 200 dentaries, and 2,000 isolated molars compare best with this
species.
Discussion--Neotoma cinerea is recognized by its large size and deep
anterolabial reentrant angle on M1/ as discussed above. N. cinerea has the
largest mean size of any species of Neotoma, and all the specimens listed
above match Recent N. cinerea in size and have he deep anterolabial reentrant
angle on M1/ when this tooth is present. This makes N. cinerea the second
best represented species in the Crystal Ball Cave assemblage after
Spermophilus townsendii. The fact that N. cinerea is abundant in the
assemblage, but not found in the cave now, while N. lepida is rare in the
assemblage, but now the only wood rat living in the cave, suggests that a
replacement of N. cinerea by N. lepida has recently taken place in the area.
The great abundance of N. cinerea remains at Sites 1 and 2 of Crystal Ball
Cave also helps substantiate my hypothesis that wood rats were the primary
means of transporting fossils, especially of large mammals, into the cave.
The dominance of N. cinerea over N. lepida in the assemblage suggests that N.
cinerea was the primary species involved in this transport.
The ecological differences between N. cinerea and N. lepida have significance
both to the replacement of the former species by the latter and to the
accumulation of fossils in the cave. Finley (1958), in his detailed study of
Colorado wood rats, found den sites to be the most limited resource for all
species. Since all wood rats prefer the same basic types of den sites, namely
rocky crags and caves, multiple species are rarely found coexisting (Finley
1958). This suggests that when conditions at Crystal Ball Cave reached a
threshold where they favored N. lepida over N. cinerea, the replacement took
place quickly. N. cinerea prefers higher elevations and latitudes than N.
lepida, and hot summers in arid regions seem to be a limiting factor for this
species (Finley 1958, Hall 1981). The changing conditions that led to the
replacement of N. cinerea by N. lepida may have been the increase in
temperature and decrease in moisture at the close of the Pleistocene, the
shift in vegetation caused by it, or both. Regarding food, Finley (1958)
stated that N. cinerea prefers soft-leaved shrubs, forbs, and montane
conifers, whereas N. lepida prefers xerophytic shrubs, forbs, cacti, and
shrubby trees.
Species of Neotoma differ somewhat in den preferences and collecting habits.
Finley (1958) stated: "Dens of N. cinerea are usually in high vertical
crevices in cliffs or caves, whereas those of . . . N. lepida are usually in
low horizontal crevices or under boulders or large fallen blocks. Dens of
[N.] cinerea usually contain larger accumulations of sticks and bones." That
N. cinerea collects more material, especially bone, is very significant since
I consider wood rats as the primary mechanism of fossil deposition at Crystal
Ball Cave. This suggests that the rate of bone deposition decreased when N.
lepida replaced N. cinerea, and it helps explain why many elements of the
present local fauna are so poorly represented and why all the dated fossils
were late Pleistocene rather than Recent in age.
A replacement of N. cinerea by N. lepida parallels the replacement of
Sylvilagus nuttallii by S. audubonii and Lepus townsendii by L. californicus
(discussed above) and helps confirm that a warming trend took place in the
recent past. Although N. cinerea still lives in the area, it seems to have
been driven to higher elevations in the Snake Range.
Material--Palate without teeth (BYUVP 7383), partial right dentary with
anterior 2/3 of M/1 (BYUVP 7391).
Discussion--Ondatra is easily distinguished from other microtine rodents by
its large size combined with rooted molars. O. zibethicus is now considered
the only extant species of Ondatra (Hall 1981), and the Crystal Ball Cave
specimens are indistinguishable from this species. A number of fossil species
have been named, but there is considerable confusion about their status
(Miller 1976). All the extinct species considered valid by Semken (1966) and
Nelson and Semken (1970) are smaller than O. zibethicus. The Crystal Ball
Cave dentary is almost as large as the largest O. zibethicus to which it was
compared. The M/1 is 7.9 mm long and 2.5 mm wide which best matches
measurements taken from Wisconsinan-age O. zibethicus specimens (Nelson and
Semken 1970). The palate is slightly smaller than the mean of O. zibethicus
but well within its range of variation.
O. zibethicus is not presently found around Gandy but occurs as close as 100
miles (170 km) to the north, east, and south (Hall 1981). Since Ondatra is a
reliable indicator of permanent water (Nelson and Semken 1970), the retreat
of Lake Bonneville and loss of perennial streams in the area probably lead to
its extirpation from the Snake Range.
Material--Two left M3/'s (BYUVP 6940 and 6981), 7 right M/3's (BYUVP
8220-8226), 15 left M/3's (BYUVP 7002, 8227-8241). Numerous other partial
jaws and isolated molars cannot be distinguished from Lagurus but lack
characters that would assign them to other species of Microtus, some of which
are likely Microtus since over a third of the microtine M/3's belong to
Microtus. Among these are a partial skull with both M1/,2/ and the posterior
incisive foramina (BYUVP 8285) and a right maxilla with M1/,2/ (BYUVP
6943).
Discussion--Microtus differs from Lagurus, the only other microtine of its
size with rootless molars, in having 3 transverse loops on M/3 rather than 4
prisms, some of which are closed triangles, and in having a large
semicircular posterior loop on M3/ rather than a simple elongate loop (Hall
1981). The 2 M3/'s and 22 M/3's from Crystal Ball Cave listed above clearly
match Microtus in this respect. There are many species of Microtus, some of
which have distinct dental characteristics and some of which do not.
The only two species of Microtus now inhabiting the Snake Range are M.
longicaudus and M. montanus, and no character could be found to distinguish
them dentally. The incisive foramina of M. longicaudus are not constricted
posteriorly as are those of M. montanus, but they differ from those of
Lagurus only in having slightly curved rather than straight external margins.
Since only the posterior end of the incisive foramina are found on skulls
that could be Microtus from Crystal Ball Cave, skulls of M. longicaudus in
the collection are indistinguishable from Lagurus. Of 13 skulls containing
incisive foramina which may be Microtus, 2 have constricted incisive foramina
as in M. montanus (listed below), and 11 compare well with M. longicaudus and
Lagurus.
Three other species of Microtus presently occur in Utah but not in the Snake
Range: M. pennsylvanicus and M. richardsonii in the central mountain ranges
and M. mexicanus in the southwestern corner of the state. M. pennsylvanicus
has a posterior loop on M2/ not found in other species, and this character
was only found on one specimen (listed below). M. richardsonii is distinctly
larger than the other species described here, and none of the microtine
specimens from Crystal Ball Cave are large enough to compare with it. M.
mexicanus is dentally indistinguishable from M. montanus and M. longicaudus,
and its incisive foramina are identical to Lagurus and similar to M.
longicaudus.
The specimens listed above are identical to Recent specimens of M.
longicaudus, M. mexicanus, and more distant ranging species. But since M.
longicaudus presently occurs at Crystal Ball Cave, while M. mexicanus occurs
more than 250 miles (400 km) to the southeast (Hall 1981), and because the
general trend in the region is for range boundaries to be migrating
northward, the Crystal Ball Cave specimens (except the few discussed below)
are referred to M. longicaudus.
Material--Two partial palates without teeth which include the posterior end
of the incisive foramina (BYUVP 8218, 8219).
Discussion--M. montanus is the only microtine of its size presently occurring
in Utah or Nevada with incisive foramina that abruptly constrict posteriorly
and are narrower posteriorly than anteriorly. The posterior ends of the
incisive foramina in these two specimens are too narrow to be M. longicaudus,
M. pennsylvanicus, M. mexicanus, or Lagurus curtatus. M. townsendii and M.
oregoni also have incisive foramina like M. montanus, but they both occur
only along the pacific coast from northern California to southern British
Columbia. Since M. montanus presently occurs in the Snake Range (Hall 1981),
the Crystal Ball Cave specimens are referred to it. M. montanus tends to
occur at higher elevations than other species of Microtus in Utah (Durrant
1952), so its presence in the assemblage suggests that conditions at the cave
during the Late Pleistocene may have been like those of higher elevations in
the Snake Range now.
Material--Partial skull with right M1/,2/ (BYUVP 6973).
Discussion--M. pennsylvanicus is unique in having a rounded posterior loop
behind the 4 closed angular sections of M2/. This single specimen from the
assemblage has this posterior loop, but the loop is not completely closed off
from the preceding triangle as in the Recent specimens to which it was
compared. Since the distinguishing character is not fully developed, the
specimen is only referred to M. pennsylvanicus. This species is not presently
found in the Snake Range, but it occurs 114 miles (190 km) east of Crystal
Ball Cave in the mountains of central Utah and is a northern species (Hall
1981). Considering the climatic shifts since the recession of Lake
Bonneville, it is not unlikely that it could have inhabited the Snake Range
during the Late Pleistocene.
Material--Skull with right I/, M2/,3/, left I/, M1/,2/ (BYUVP 6899), left
dentary with M/1,/2,/3 (BYUVP 6977), left dentary with M/2,/3 (BYUVP 6986),
28 right M/3's (BYUVP 8242-8270), 9 left M/3's (BYUVP 8271-8280). Numerous
partial jaws and isolated molars may be L. curtatus but cannot be
distinguished from Microtus longicaudus (as discussed above).
Discussion--The differences between Lagurus and Microtus are discussed above.
L. curtatus, the only North American species of Lagurus, is distinguished
from Old World representatives by having 4 instead of 5 closed triangles on
M/3 and cement present in the reentrant angles of the molars (Hall 1981).
This species presently occurs in the Snake Range and northward into Canada
(Hall 1981). Lagurus specimens are nearly twice as abundant as those of
Microtus in the assemblage, but since no information on their Recent relative
abundance or habitat differences could be found, it is difficult to know the
reason for this.
Material--Lower incisor (BYUVP 7459), right C/1 (LACM 123675), partial left
M/1 (BYUVP 7460). The frontal region of a skull (LACM 123676) and an anterior
fragment of a left dentary without teeth (BYUVP 7458) also compare favorably
with this species.
Discussion--These specimens are indistinguishable from specimens of Recent C.
latrans, generally recognized as the only species of coyote in the
Pleistocene or Recent (Giles 1960). Dentally, C. latrans falls within the
wide range of variation of the domestic dog, C. familiaris (Anderson 1968),
so the possibility that the Crystal Ball Cave specimens are C. familiaris
cannot be totally eliminated. But C. latrans is presently very abundant
around the cave (J. C. Bates 1983 personal communication, Hall 1981) and has
been recognized from nearby Pleistocene assemblages that have better
stratigraphic control (Kurten and Anderson 1972, Miller 1979), so there is no
reason to believe it would not be found in the assemblage. Also, domestic
dogs tend to have many more tooth malformations than coyotes (Anderson 1968)
and none are seen in the Crystal Ball Cave specimens. Lack of human fossils
and artifacts at Crystal Ball cave makes domestic dogs less likely to be
present than at sites that contain such remnants of human occupation.
Although residents of Gandy have domestic dogs that sometimes roam on Gandy
Mountain, the lack of any canid specimens in the assemblage that cannot be
referred to native species also supports the conclusion that the Crystal Ball
Cave specimens are C. latrans.
Discussion--Identification of these canid fossils is based on their size,
being substantially larger than C. latrans but considerably less robust than
C. dirus. They do, however, fit within the large size range of C. familiaris,
so the identification must be tentative. Goodrich (1965) reported C. lupus
from Smith Creek Cave but did not describe the material. C. lupus has been
reported living in the Snake Range in Recent times (Hall 1981) although Man
has now reduced its range and numbers considerably.
Material--Skull with right P1/,2/,4/, left P4/, M2/ (BYUVP 8299), posterior
portion of right maxilla with M1/,2/ (BYUVP 7466), partial left maxilla with
M1/,2/ (BYUVP 7467), two right C1/'s (BYUVP 7468, 7470), left C1/ (BYUVP
7469), right P4/ (BYUVP 7474), left P4/ (BYUVP 7471), right dentary with M/2
(BYUVP 7461), posterior portion of right dentary with P/4, M/1,/2 (BYUVP
7463), left dentary with M/1,/2 (BYUVP 7464), anterior portion of left
dentary with M/1,/2 (BYUVP 7462), right P/4 (BYUVP 7475), left P/4 (BYUVP
7472). An anterior fragment of a right dentary without teeth (BYUVP 7465) and
an anterior fragment of a left dentary without teeth (BYUVP 7476) also
compare favorably with this species.
Discussion--Vulpes is distinguished from Urocyon by the configuration of the
crest on top of the skull and the lack of a prominent "step" on the
posteroventral margin of the dentary. The ventral margin of the dentary of
Vulpes curves upward posteriorly beginning at the posterior end of the tooth
row while in Urocyon it remains uncurved well behind the tooth row all the
way to the "step." Urocyon, which ranges from the cave site southward and
throughout North America, is intermediate in size between V. vulpes and V.
velox. Four of the Crystal Ball Cave specimens include the posterior dentary
and lack the "step" characteristic of Urocyon, and all the Crystal Ball Cave
specimens are larger than the largest Urocyon specimen examined but compare
well in size and shape to V. vulpes.
V. vulpes does not presently occur around Crystal Ball Cave but V. velox and
U. cinereoargenteus do (J. C. Bates 1983 personal communication, Hall 1981).
The presence of the more northern V. vulpes but not the more southern U.
cinereoargenteus in the cave assemblage represents a northward shift of the
boundary between these two species. The ranges of V. vulpes and U.
cinereoargenteus do overlap to a degree now, but in the western United States
the overlap is not great, and where it does occur V. vulpes favors the higher
elevations and U. cinereoargenteus the lower elevations (Hall 1981). Based on
range maps in Hall (1981), the range of V. vulpes in the western United
States is quite scattered, suggesting that it is relectual and that this
species is diminishing in numbers there. U. cinereoargenteus has a distinct
northern boundary across Utah and Nevada with no remnant populations,
suggesting that this species has been making a northward invasion. The
Crystal Ball Cave assemblage confirms that U. cinereoargenteus has been
expanding its range at the expense of V. vulpes.
Material--Left dentary with P/3 and partial M/1 (BYUVP 7477), posterior
portion of left M/1 (BYUVP 7479). A partial left dentary with M/2 (BYUVP
7478) also compares favorably with this species.
Discussion--V. velox and V. macrotis are now considered conspecific (Hall
1981). The dentary (BYUVP 7477) lacks the "step" of Urocyon, and the M/1
lacks a small cuspule found on the posterolabial margin of the main cusp of
all the Urocyon specimens but none of the Vulpes specimens examined. The
Crystal Ball Cave specimens listed above are smaller than U. cinereoargenteus
but may be similar in size to the smaller U. littoralis, which is known only
from islands along the coast of southern California (Miller 1971).
Since V. velox still lives around Crystal Ball Cave (J. C. Bates 1983
personal communication), its presence in the assemblage is not surprising.
Its low frequency compared to the now-extirpated V. vulpes suggests that it
may not have always inhabited the area, may have inhabited it in much smaller
numbers, or may have had a different microhabitat causing it to frequent the
cave area less than V. vulpes. The ranges of V. vulpes and V. velox presently
overlap to a degree, especially in the midwest, but in the western United
States this overlap is small (Hall 1981). Although V. velox occurs in the
Snake Range now, it is a more southern species than V. vulpes so its northern
range extensions may be of Recent age.
Material--Left M1/ (BYUVP 7487), right dentary with P/2,/3, M/1,/2 (BYUVP
7483), partial right dentary without teeth (BYUVP 7484), left dentary with
M/1,/2 (BYUVP 7488), left dentary with M/1 (BYUVP 7485), partial left dentary
with M/1,/2 (BYUVP 7486).
Discussion--All these Mustela specimens compare best in size with M. frenata,
which presently lives around Crystal Ball Cave. The size range of M. frenata
is overlapped by the smaller but more variable M. erminea (Kurten and
Anderson 1980) which also ranges in the cave area (Hall 1981). The specimens
could belong to M. erminea since this species is dentally similar to M.
frenata. M. rixosa is always smaller and M. nigripes and M. vison are always
considerably larger than the Crystal Ball Cave specimens. M. frenata was the
most abundant mustelid at Smith Creek Cave, but M. erminea was also present
(Miller 1979). Since all the Crystal Ball Cave specimens fall in the narrow
size range of M. frenata, they are referred to this species.
Material--Left M1/ (BYUVP 7482). A juvenile left dentary without teeth
(BYUVP 7491) also compares well with this species.
Discussion--This isolated tooth was compared with a variety of Recent
mustelids and other small carnivores and found most similar to M. vison. This
is North America's largest extant species of Mustela (although the extinct
sea mink, M. macrodon, was larger) and is distinctly larger than but similar
in shape to M. frenata (described above). M. vison was recovered from Smith
Creek Cave (Miller 1979) and presently occurs 100 miles (160 km) north and
east of Crystal Ball Cave (Hall 1981), but it does not currently live in the
Snake Range. This species requires lakes or streams to survive (Hall 1946),
so its extirpated nature in the Snake Range may have been due to the
recession of Lake Bonneville and/or loss of perennial streams in the area at
the end of the Pleistocene.
M. vison is sometimes confused with M. nigripes since both are of similar
size (Kurten and Anderson 1980), and no distinction in isolated molars could
be found in the literature. M. nigripes is currently endangered, and no
comparative material was available. It has never been reported from western
Utah or Nevada, so the Crystal Ball Cave specimens are referred to M. vison,
which is known to have lived in the area.
Material--Left dentary with M/1 (BYUVP 7480), left M/1 (BYUVP 7481). The
anterior portion of a right dentary without teeth (BYUVP 7489) and the
posterior portion of a right dentary without teeth (7523) probably also
belong to this taxon.
Discussion--Anderson (1970), in her systematic review of the genus Martes,
considered M. nobilis (found in four caves in Wyoming, Idaho, and northern
California) to be a distinct species from M. americana. Of the two, M.
nobilis is larger, and its lower carnasial has a relatively shorter trigonid.
The lower canines of M. nobilis sometimes have faint grooves on the external
surface not found in M. americana (Anderson 1970). The only other species of
Martes presently living in Utah is M. pennanti, the fisher. It is
considerably larger than M. americana, M. nobilis, and the Crystal Ball Cave
specimens. Neither M. americana nor M. pennanti currently live in the Snake
Range, but both occur in the mountains of central Utah and northward.
BYUVP 7480 is as large as the largest M. americana specimen to which it was
compared, and judging from the incisor socket, its incisor was slightly
larger. The other specimens are the same size as most Recent M. americana
specimens. Both lower carnasials match perfectly in shape with M. americana
and do not show a relatively shorter trigonid, so they are assigned to M.
americana. A right M1/ of M. nobilis was recovered from Smith Creek Cave
(Miller 1979) but M. americana has never been reported. The ecological and
chronological separation of these two species in the Snake Range is,
therefore, problematic. Brown (1971) listed M. americana as one of eight
species of boreal mammals that presently range in the Sierra Nevada and the
Rocky Mountains but on none of the isolated Great Basin ranges in between.
This citing demonstrates that M. americana did range at least as far east in
the Great Basin as the Snake Range before becoming extirpated.
Type--Anterior portion of skull including a complete palate except the most
posterior (smallest) socket of each M1/ and extending posteriorly to include
the entire anterior wall of the braincase (BYUVP 7490, see figure 5). Only
the right P4/ was found in situ, but a right and left M1/ (previously
cataloged as BYUVP 7492 and 8298 respectively) fit perfectly into the sockets
of the type specimen where they have been permanently mounted. The type
specimen is of a young adult based on complete fusion of the premaxillae,
maxillae, nasals, and frontals and on lack of significant tooth wear. Both
the skull and isolated M1/'s were recovered from Site 1, Channel A, Crystal
Ball Cave, Millard County, Utah (see figures 1 and 3) by Wade E. Miller and
party on March 19, 1977. The type specimen is housed at the Brigham Young
University Vertebrate Paleontology Laboratory.
Diagnosis--Brachyprotoma brevimala has a short face and a maxillary tooth
formula of I3/-3/, C1/-1/, P2/-2/, M1/-1/ as in B. obtusata. Face and
maxillary dental measurements average 15% smaller than those of B. obtusata.
B. brevimala is distinguished from B. obtusata by P4/ being transversely
narrower and having a more posteriorly directed lingual cusp, and by M1/
being more reduced and distinctly shorter anteroposteriorly. In other known
characters B. brevimala is equivalent to B. obtusata. B. brevimala has the
most reduced P4/ and M1/ of any known skunk.
Description--The maxillary dental formula of I3/-3/, C1/-1/, P2/-2/, M1/-1/
is known among the mustelids only in two genera of skunks, Conepatus and
Brachyprotoma (although I found one abnormal Recent Spilogale putorius
specimen with this formula). The Crystal Ball Cave specimen is clearly a
skunk (subfamily Mephitinae) based on the presence of only 2 pairs of upper
premolars (mephitines have 2 or 3, all other mustelids have 3 or 4), the
small size (only the subfamilies Mustelinae and Mephitinae have such small
adult individuals), the lingual cusp of P4/ extending from the middle of the
tooth (as opposed to the more anterior extension in the mustelines), M1/
being anteroposteriorly shorter labially than lingually (mustelines have the
opposite condition), and the internal nares extending almost as far
anteriorly as the posterior end of the tooth row (they are much more
posterior in mustelines).
Compared to extant mephitines the Crystal Ball Cave specimen represents an
individual of similar size to Spilogale but much smaller than Conepatus and
Mephitis. The palate is shorter and wider than that of Spilogale putorius,
but the interorbital breadth shows that the type specimen represents a larger
individual than the average S. putorius. The P4/ is similar to Spilogale,
differing only in having the lingual cusp slightly more posterior, but it is
proportionally much narrower than the P4/ of Mephitis and Conepatus. The
M1/'s are proximo-distally shorter than any of the living mephitines
(especially Conepatus and Mephitis that have large square M1/'s) and are
closest to Spilogale in shape and cusp pattern. The rostrum of the type
specimen is shorter than that of Spilogale, matching that of Conepatus in
proportions. The external nare is steep as in Conepatus, but it is relatively
small and round as in Spilogale. Both infraorbital canals are single rather
than double or triple, a species-diagnostic character in Conepatus (Hall
1981) but variable in Mephitis and Spilogale.
In addition to the three extant genera, three fossil genera have been named:
Buisnictis, Brachyprotoma, and Osmotherium (Kurten and Anderson 1980).
Osmotherium can be ruled out since it is large and very similar to Mephitis
(Kurten and Anderson 1980), the living skunk genus that is most distinct from
the Crystal Ball Cave specimen. Both Buisnictis and Brachyprotoma are small
and have proportionally short jaws like the Crystal Ball Cave specimen.
Buisnictis has been recovered from Late Pliocene deposits of southwestern
Idaho (Bjork 1970) and Middle Pliocene to Early Pleistocene deposits of
Kansas and Oklahoma (Hibbard 1941, 1950, 1954), but it has no record in the
Late Pleistocene or Recent. Buisnictis has a short jaw with crowded
premolars, but it differs from the Crystal Ball Cave specimen in having 3
pairs of upper premolars instead of 2 (Kurten and Anderson 1980). Based on an
illustration by Hibbard (1954), the P4/ of Buisnictis has its lingual cusp
extending from the anterior part of the tooth as in the mustelines, and the
M1/ is distinctly longer than that of the Crystal Ball Cave specimen. These
morphologic and age differences show that the Crystal Ball Cave specimen is
distinct from Buisnictis.
The Crystal Ball Cave specimen matches the genus Brachyprotoma in having
short jaws, only 2 pairs of upper premolars, P4/ and M1/ similar in shape and
cusp pattern to Spilogale, and in the age of deposits in which they have been
recovered. Until recently Brachyprotoma was only known from a few early
Pleistocene to early Recent age ave deposits in the eastern United States.
But during the period of this study P. M. Youngman (1984 personal
communication) recovered several Brachyprotoma specimens from two cave
deposits in the Yukon Territory of Canada. Although no previous Brachyprotoma
specimens have been reported closer than 1130 miles (1880 km) from Crystal
Ball Cave, morphology clearly allies the Crystal Ball Cave specimen with this
genus. But there are specific differences between the Crystal Ball Cave
specimen and other skulls which have been assigned to the genus
Brachyprotoma. To test the amount of variation to be expected within a
species of skunk, I measured 73 specimens of Recent Spilogale putorius, 60
from the Harvard University Museum of Comparative Zoology and 13 from the
Brigham Young University Monte L. Bean Museum. Spilogale putorius makes a
good standard for the expected individual variation in species of
Brachyprotoma, both because Spilogale is probably the most closely related
extant genus to Brachyprotoma and because S. putorius borders on being
divisible into multiple species (although most workers presently consider it
a single species). Based on the great amount of variation seen between the
Crystal Ball Cave specimen and other skulls assigned to the genus
Brachyprotoma compared with the amount of variation seen among individuals of
S. putorius, I believe the Crystal Ball Cave specimen warrants the status of
a new species.
The B. brevimala type is smaller than specimens of B. obtusata in most
measured characters, averaging about 15% smaller (see table 3). The greatest
differences occur in P4/ and M1/, which are the most varied maxillary teeth
between skunk taxa. The mean length of P4/ in B. obtusata is only 7% greater
than in B. brevimala while the mean width is 22% greater. The lingual cusp of
P4/ in B. brevimala also points more posteriorly than in B. obtusata, being
nearer M1/ at its lingual tip rather than closer at its base or parallel as
in B. obtusata. The M1/ of B. obtusata is 16% transversely wider on the
average, but the labial anteroposterior length is 30% greater and the lingual
anteroposterior length is 59% greater than in the B. brevimala type on the
average. Since there is only minor variation in these characters among B.
obtusata skulls (see table 3) but distinct difference between them and the
Crystal Ball Cave specimen, and because the differences between the B.
brevimala type and specimens of B. obtusata are far greater than would be
expected within a species (based on the variation found among 73 individuals
of Spilogale putorius, the most closely related extant species), erection of
a new species for the Crystal Ball Cave specimen is clearly justified.
Discussion--Brachyprotoma specimens have been previously recovered from the
following deposits of Early Pleistocene to Early recent age: Port Kennedy
Cave and Frankstown Cave, Pennsylvania (Cope 1899, Peterson 1926), Cumberland
Cave, Maryland (Gidley and Gazin 1938), Crankshaft Cave and Brynjulfson Cave,
Missouri (Oesch 1967, Parmalee and Oesch 1972, Parmalee et al. 1969), Connard
Fissure, Arkansas (Brown 1908), and two caves in northern Yukon Territory,
Canada (P. M. Youngman 1984 personal communication). Most of these specimens
are lower jaws, and the only 7 skulls (or skull fragments) that have been
previously reported are Carnegie Museum 11057A and 20233, American Museum of
Natural History 11772 and 12426, U.S. National Museum 8155 and 11960, and a
specimen identified as Carnegie Museum 308 by Oesch (1967) but which does not
correspond to that number in the Carnegie Museum catalogs (M. R. Dawson 1984
personal communication). Parmalee et al. (1969) illustrated this latter
specimen but did not identify it by catalog number.
Cope (1899) named Mephitis (Spilogale) obtusatus, for a single small dentary
from Port Kennedy Cave, but E. D. Cope died before the completion of this
paper, and a footnote stated that "none of the specimens labelled by Prof.
Cope bear this name." Brown (1908) named the genus Brachyprotoma, and he
considered M. obtusatus to belong to this genus as well as M. fossidens and
M. leptops, two species named by Cope previous to the naming of M. obtusatus.
From Connard Fissure Brown (1908) reported B. fossidens, B. leptops, and B.
obtusatus based on dentaries, and he named B. pristina based on two partial
skulls and three dentaries (the skull cataloged as American Museum of Natural
History 12426 is the type for the genus and species) and B. spelaea based on
one dentary. The dentaries Brown (1908) identified as B. fossidens and B.
leptops are far too large to belong to the same genus as the small specimens
he identified as B. obtusatus, B. pristina, and B. spelaea, and no one since
has considered these two species as belonging to the genus Brachyprotoma.
Later Hay (1923) named B. putorius from Frankstown Cave. Peterson (1926)
identified material from Frankstown Cave as B. obtusata, correcting the
specific ending to match the gender of the generic name.
The naming of multiple species of Brachyprotoma in the early publications
listed above has been widely criticized by later workers because the
variation among specimens is less than that seen within living species. Hall
(1936) and Kurten and Anderson (1980) considered the genus Brachyprotoma to
be clearly monotypic with the only valid species being B. obtusata, the
earliest named species that can be applied to the genus. The Brachyprotoma
skull from Crystal Ball Cave is the first specimen of Brachyprotoma distinct
enough from B. obtusata to warrant the erection of an additional species of
this genus.
Concerning the paleoecology of Brachyprotoma, Kurten and Anderson (1980)
stated that this genus has always been associated with boreal faunas although
other skunk genera were also recognized at each site. This matches the "more
boreal than present" nature of the Crystal Ball Cave assemblage and suggests
that the post-Pleistocene climatic shift may have lead, directly or
indirectly, to the extinction of Brachyprotoma. Since fossils of
Brachyprotoma are only found in a few deposits and even then are few in
number, this genus probably never had a high density of individuals in
life.
The Brachyprotoma brevimala type was first misidentified as Spilogale (Heaton
1984), the most similar living genus. Miller (1982) reported cf. Spilogale
from Crystal Ball Cave, possibly based on this same specimen. Mephitis was
also mentioned in my preliminary report (Heaton 1984), but further
examination proved that the anterior right dentary (BYUVP 7489) upon which
the identification was based was equally referable to Martes americana, which
is represented by additional material. Although both Mephitis mephitis and
Spilogale putorius (=gracilis) now inhabit the Snake Range (Hall 1981), and
Spilogale has been recovered from deposits over 12,000 years old in Smith
Creek Cave (Mead et al. 1982), their presence is unconfirmed in the Crystal
Ball Cave assemblage.
Since Brachyprotoma seems to have lived contemporaneously with other skunk
genera, it is interesting to speculate about how their niches varied. All
living skunks tend to be nocturnal and omnivorous, so they are rarely tied to
specific foods or habitats. Minor niche differences do occur between living
North American genera: Spilogale is the most carnivorous, Mephitis the most
herbivorous, and Conepatus the most insectivorous. Spilogale has narrow sharp
teeth, Conepatus at the other extreme has very broad teeth, and Mephitis is
intermediate but has the longest tooth rows. Brachyprotoma (especially B.
brevimala) has pushed the narrowing of the teeth seen in Spilogale to an
extreme, converging on the carnivorous genus Mustela. This suggests that
Brachyprotoma was more carnivorous than any of the living skunks.
Why Brachyprotoma lost P2/ and shortened its tooth rows, paralleling the
genus Conepatus, is a mystery. Members of the genus Mustela have longer tooth
rows than skunks, so in that respect Brachyprotoma diverged from Mustela.
Brachyprotoma was trending in a direction that is difficult to explain.
Brachyprotoma also did not survive the post-Pleistocene changes as did the
aforementioned genera (although some species were lost and ranges altered).
I propose that these two facts are correlated. Brachyprotoma was probably
adapting to a specialized niche that existed during the Pleistocene but
disappeared during the Recent. I also propose that this specialization was a
feeding habit and/or preference for a particular prey item since the
specializations discussed are all dental. No postcranial material has been
reported to document additional specializations, and skunks' most diagnostic
characters, scent glands and color patterns, are in the soft anatomy which is
obviously unavailable. With such limited data (about 27 specimens from 9
sites), further speculation would be unwarranted. All that can be concluded
is that Brachyprotoma was restricted to boreal conditions, was widespread in
North America, was probably low in density, and did not survive the
post-Pleistocene changes.
The evolution of the genus Brachyprotoma has been discussed by Kurten and
Anderson (1980). They stated that it seems most closely related to Spilogale,
but both were probably derived from the Mio-Pliocene genus Promephitis. No
intermediate forms are available to show the exact phylogeny, however. Some
speculation can be made about the relationship of B. brevimala to B.
obtusata. B. brevimala has gone to a greater extreme in the characters that
differentiate Brachyprotoma from other skunks (shorter face and narrower
teeth) and is therefore more specialized. Since specialists almost always
evolve from generalists, B. brevimala probably evolved from B. obtusata. The
fact that B. obtusata has been found in deposits from early Pleistocene to
early Recent age (Kurten and Anderson 1980) while B. brevimala is known only
from a late Pleistocene to Recent deposit also supports this conclusion.
Material--Partial left ectocuneiform (BYUVP 7530), claw (BYUVP 7497). Miller
(1982) reported cf. Smilodon from Crystal Ball Cave based on a single
vertebra (W. E. Miller 1983 personal communication), but this specimen is
apparently lost (possibly due to an explosion that affected the
collection).
Discussion--The ectocuneiform is dense, worn, and coated with a calcite
crust. The claw is missing the outer plates but is otherwise in good
condition. The specimens were compared with Smilodon and Felis atrox, the
only two late Pleistocene cats large enough to be considered, and both
compare best with Smilodon (W. E. Miller 1984 personal communication). The
ectocuneiform was previously referred to Panthera atrox (Heaton 1984), but
comparison with actual specimens rather than casts shows that it was clearly
Smilodon. The only previous citing of Smilodon in Utah is from the Silver
Creek fauna of north-central Utah (Miller 1976), but it has been found in
Pleistocene assemblages throughout North America.
Kurten and Anderson (1980) considered S. fatalis to be the only valid species
of late Pleistocene Smilodon in North America, but it has been known by many
other names. Based on this synonymy, the Crystal Ball Cave specimens are
referred to S. fatalis although they are doubtfully species specific.
Material-First right metacarpal (BYUVP 7502), 4 claws (BYUVP 7498-7501).
Discussion-F. concolor is the only cat of its size presently living in North
America, but similar-sized species of Acinonyx and Homotherium existed during
the Pleistocene. Lynx and other species of Felis (disregarding those often
placed in the genus Panthera) are distinctly smaller than F. concolor, and
Smilodon, Panthera atrox, and P. onca are distinctly larger. The Crystal Ball
Cave specimens were compared with material of Felis species, Acinonyx, and
Homotherium at the Los Angeles County Museum and found to match perfectly in
size and shape with F. concolor but to clearly differ from the other felids
mentioned. F. concolor presently lives throughout the Snake Range (Hall
1981), and J. C. Bates (1983 personal communication) reported a citing in the
Snake Valley near Gandy as well as many higher in the mountains.
Material--Right C1/ (BYUVP 7494), right P/4 (BYUVP 7496). The anterior
portion of a right maxilla without teeth (BYUVP 7495) is probably also
referable to Lynx.
Discussion--L. rufus currently inhabits the area of Crystal Ball Cave (J. C.
Bates 1983 personal communication) while L. canadensis ranges only as close
as central Utah and northward and prefers colder climates (Hall 1981). L.
canadensis is slightly larger than L. rufus and has considerably larger feet
(Ingles 1965). The specimens recovered fall in the size range of both L.
rufus and L. canadensis, but they tend to be closer in size to L. rufus. None
of the claws recovered could be referred to this genus, so the difference in
foot size was not helpful. Since L. rufus presently lives around the cave,
the specimens are referred to it.
Material--Left cuneiform (BYUVP 7542), right lunar (BYUVP 7544), 2 right
scaphoids (BYUVP 7549, 7550), right magnum (BYUVP 7561), second phalanx (LACM
123683), third phalanx (BYUVP 7595). A juvenile left P/2 (BYUVP 7623), a
partial juvenile first phalanx (BYUVP 7586), a second phalanx (BYUVP 7588),
3 partial third phalanges (BYUVP 7596, 7607, 7608), and a distal sesamoid
(BYUVP 7622) probably belong to this species also. Phalanx measurements are
listed in tables 4, 5, and 6.
Discussion--Several species of large horses have been recognized from the
late Pleistocene of western North America. The Rancho La Brea asphalt
deposits have yielded a single species of large horse (Savage 1951) usually
referred to E. occidentalis (Merriam 1913, Stock 1963, Willoughby 1974),
although the validity of this name has been questioned (Miller 1971). Based
on comparative material and measurements made by Willoughby (1974), the large
Crystal Ball Cave horse is distinct from the Rancho La Brea horse in having
more transversely broad phalanges (see figures 6, 7, and 8) and carpals with
relatively larger articulation surfaces. The Crystal Ball Cave specimens are
distinctly larger than E. niobrarensis based on measurements given me by A.
H. Harris (1983 personal communication) and in Harris and Porter (1980). A.
H. Harris (1983 personal communication) also provided me with measurements of
E. pacificus (although the validity of this species has been questioned by
Savage 1951) from Fossil Lake, Oregon, and phalanges of this species match
well in size with the large Crystal Ball Cave horse but are not as
transversely broad.
Gazin (1936) listed measurements of the type specimen of E. scotti, and of
all specimens and data seen, only it has phalanges that are as transversely
broad as the Crystal Ball Cave specimens. The second phalanx (LACM 123683) is
slightly larger than the E. scotti type but has identical proportions (see
figure 7), and the third phalanx (BYUVP 7595), although smaller because it is
of a subadult, has the same proportions as the anterior third phalanges of
the E. scotti type (see figure 8). Dalquest (1964) stated that E. scotti was
very heavily built, and this would suggest that the foot and toe bones are
broad compared with other species of Equus. The large carpals from Crystal
Ball Cave mentioned above, especially the cuneiform and magnum, are broad and
have much larger articulation surfaces than the Rancho La Brea horse. Based
on this limited information in the literature, the largest carpals listed
above compare most favorably with E. scotti also.
E. scotti was originally named and described from Texas by Gidley (1900), and
most specimens have been found in that state (Dalquest 1964, Gidley 1903,
Johnston 1937). Hopkins et al. (1969) recovered a left metatarsal from the
Late Pleistocene American Falls Lake Beds of southeastern Idaho that they
referred to E. scotti. It is therefore not unlikely that E. scotti lived in
Utah. A large horse was represented at Smith Creek Cave by a single vestigial
metapodial (Miller 1979), but no attempt was made to identify it to
species.
BYUVP 7588 is not as laterally broad as LACM 123683 but is too large to
belong with the smaller species. The epiphysis is not fully fused, showing
that it represents a subadult. It is the only bone from Crystal Ball Cave
that matches well with the Rancho La Brea horse, although it is slightly
smaller. But since it may differ by only individual, foot, or age variation
from the better represented E. cf. scotti, it is tentatively referred to that
species.
Material--Right M3/ (LACM 123677), thoracic vertebra (BYUVP 7687), 3 right
pisiforms (BYUVP 7536-7538), left pisiform (BYUVP 7539), 2 right cuneiforms
(BYUVP 7540, 7541), 4 right lunars (BYUVP 7543, 7545-7547), partial left
lunar (BYUVP 7548), 4 right scaphoids (BYUVP 7551-7558), 4 partial left
scaphoids (BYUVP 7555-7558), 2 right trapezium-trapezoids (BYUVP 7559, 7560),
2 right magnums (BYUVP 7562, 7563), partial right magnum (BYUVP 7564), left
magnum (LACM 123678), 2 partial right unciforms (BYUVP 7565, 7566), proximal
tibia epiphysis (BYUVP 7570), distal epiphysis of right tibia (BYUVP 7571),
partial distal epiphysis of left tibia (BYUVP 7572), right calcaneum (LACM
123679), left calcaneum (BYUVP 7573), right astragalus (BYUVP 7575), right
juvenile astragalus (BYUVP 7574), left astragalus (LACM 123680), right
navicular (BYUVP 7576), left navicular (BYUVP 7577), left cuboid (BYUVP
7579), right meso-ento (BYUVP 7578), proximal portion of left metatarsal
(BYUVP 7567), 2 distal metapodial epiphyses (BYUVP 7568, 7569), 6 first
phalanges (BYUVP 7580, 7581, 7583, LACM 123684, 123685), 3 partial first
phalanges (BYUVP 7582, 7584, 7585), 5 second phalanges (BYUVP 7589, 7593,
7594, LACM 123684, 123685), 4 partial second phalanges (BYUVP 7587,
7590-7592), 5 third phalanges (BYUVP 7597, 7600, 7601, 7605, 7606), 2 partial
third phalanges (BYUVP 7602, 7603), juvenile third phalanx (BYUVP 7610), 11
proximal sesamoids (BYUVP 7611-7621). Phalanx measurements are listed in
tables 4, 5, and 6.
Discussion--In addition to the fossils of large horses from Crystal Ball Cave
(referred to E. cf. scotti) are numerous bones of small horses. Some of these
compare well with E. conversidens, the species to which most small
Pleistocene North American horse fossils have been assigned, while others do
not. Considerable time has been spent evaluating the size and morphologic
variation among these bones and comparing the results with descriptions and
measurements in the literature. But both complexities within this collection
and disagreements regarding valid species in the literature have prevented
positive species identification of these small horse bones.
E. conversidens (Owen 1869) has been considered by some to be the only
species of small Pleistocene horse in North America (Harris and Porter 1980,
Miller 1971), and most other named species of small Pleistocene horses have
at some time been synonymized with this species (Dalquest and Hughes 1965,
Hibbard 1955, Hibbard and Taylor 1960). However most workers presently
recognize at least two species. Owen (1869) named E. tau at the same time he
named E. conversidens. Poor illustrations of the type specimens have caused
some workers to consider E. conversidens and E. tau synonymous (Hibbard
1955). But Dalquest (1979) and Mooser and Dalquest (1975), after researching
the early descriptions (the type specimen of E. tau is lost), considered
these two species distinct. The teeth that Mooser and Dalquest (1975)
assigned to E. tau are smaller than those of E. conversidens, and the
metapodials are longer and more slender. Skinner (1942) assigned a first
phalanx from Papago Springs Cave, Arizona to E. tau because it was much
narrower than those of E. conversidens from the same assemblage. But based on
his measurements this phalanx is narrower transversely than
anteroposteriorly, making it doubtful of being horse at all.
Hay (1915) named E. francisci, which was synonymized with E. conversidens by
Hibbard and Taylor (1960). But Lundelius and Stevens (1970) reprepared the
metatarsal of the type specimen and found it to be distinctly longer and
narrower than that of E. conversidens. Lundelius and Stevens (1970) therefore
considered E. francisci a valid species, and they synonymized E. quinni
(based on the similar long metatarsal) and Onager zoyatalis (based on dental
similarities) to it. Dalquest (1979) considered E. francisci, as well as E.
littoralis, E. achates, and E. quinni, to be synonymous with E. tau, and he
considered E. conversidens and E. tau the only two valid species of small
Pleistocene North American horses.
Based on an illustration in Lundelius and Stephens (1970), the M3/ of E.
francisci is distinctly wider transversely than that of E. conversidens
although they are of similar anteroposterior length. LACM 123677, although
quite worn, has the same width and length as the E. francisci type and has an
enamel pattern most similar to it also. Dalquest (1979) synonymized E.
francisci with E. tau, but the M3/ of the lectotype of E. tau illustrated by
Mooser and Dalquest (1975) is not transversely broad like the E. francisci
type and Crystal Ball Cave M3/. Unfortunately the only phalanx measurements
given in the literature are for E. conversidens, except the questionable
first phalanx assigned to E. tau by Skinner (1942).
The only phalanges from Crystal Ball Cave that compare well with measurements
of E. conversidens phalanges in the literature are three of the five second
phalanges (see figure 7). The other two second phalanges (BYUVP 7593, 7594)
are distinctly smaller than any assigned to E. conversidens yet have complete
epiphyseal fusion. All nine first phalanges are from individuals intermediate
in size between those represented by the two sets of second phalanges, and
all are small compared with the first phalanges assigned to E. conversidens
in the literature (see figure 6). Six of the seven third phalanges articulate
well with the three larger second phalanges yet are smaller than the third
phalanges assigned to E. conversidens in the literature (see figure 8). The
other third phalanx (BYUVP 7600) is larger than any assigned to E.
conversidens and too large to articulate with any of the second phalanges
under discussion.
It is important to consider sexual dimorphism, individual variation, and
variation among different feet of the same individual to see how much
variation is expected within a species. Willoughby (1974), in a table of bone
measurements from 25 species and races of Equus, listed mean dimensions for
both sexes with respect to two characters: metacarpal mid-width and
metacarpal mid-width divided by length. Metacarpals of males had a mid-width
of 3.1% to 7.3% greater than females and a mid-width divided by length of
2.3% to 6.9% greater than females. Species with more sexual dimorphism in
metacarpal width tended to also have more dimorphism in width relative to
length, so male metacarpals tend to be more robust and just slightly longer
than female metacarpals. These measurements show that sexual dimorphism is
not great in Equus and certainly not sufficient to have caused the
variability seen among the small Crystal Ball Cave equids.
Howe (1970), in a study of Equus (Plesippus) simplicidens, showed that
individual variation in bone size can be greater than previously thought.
Because the large number of specimens at Nebraska's Broadwater Quarry fell
into a single size curve with no gaps, he concluded that they all represent
a single species, and he synonymized a number of species which had previously
been named based on limited material at other sites. Table 5 of Howe (1970)
shows that the largest metacarpal and metatarsal lengths and widths average
32% larger than the smallest corresponding measurements, and none are more
than 36% larger. Even with a sample size of 97 to 190, the metapodials
measured by Howe (1970) show less variation than do the few second and third
phalanges from Crystal Ball Cave.
Isolated front and rear phalanges are usually indistinguishable and therefore
have an additional degree of variation. Front and rear phalanx measurements
were taken from recent E. caballus and E. burchelli specimens, and the larger
measurements for each species averaged 4.2% larger than the smallest
corresponding measurements with a maximum of 9.4% larger. But even this much
variability, in addition to sexual and individual variation, does not
adequately account for the great size range among the small Crystal Ball Cave
equids.
Six measurements of the 5 second phalanges from Crystal Ball Cave (excluding
those referred to E. scotti) show that the largest measurements are 24% to
43% larger than the smallest corresponding measurements with an average of
31.5% larger. Eleven measurements of the 9 third phalanges from Crystal Ball
Cave show that the largest measurements are 7% to 122% larger than the
smallest corresponding measurements with an average of 50.7% larger.
Considering the second and third phalanges separately, each have enough
variation to make it marginal whether they could all be assigned to the same
species considering sexual, individual, and foot variation. The variation
seems even more extreme when one considers that the smallest second phalanges
(BYUVP 7593, 7594) are from much smaller individuals than the smallest third
phalanx, and the largest third phalanx (BYUVP 7600) is from a larger
individual than the largest second phalanx. This is far more variation than
can be accounted for by the sexual, individual, and foot variation for a
single species as discussed above, and it suggests that multiple species of
horse smaller than E. cf. scotti are represented at Crystal Ball Cave.
Finding a dividing line between two species in this material is nearly
impossible, however. Most of the material could be assigned to a species of
horse 15% smaller than E. conversidens, but the two smallest second phalanges
(BYUVP 7593, 7594) and the largest third phalanx (BYUVP 7600) seem too far
from the mean to belong to this supposed species. Until more phalanx
measurements are available for small Pleistocene horses other than E.
conversidens, it is difficult to determine how many species are represented
by the smaller Equus fossils from Crystal Ball Cave and whether most of the
material represents an unusually small variety of E. conversidens, a species
distinct from E. conversidens such as E. tau and/or E. francisci, or both.
Material--Right scaphoid (LACM 123686), left scaphoid (LACM 123687), left
lunar (BYUVP 7624), left magnum (BYUVP 7625), right unciform (BYUVP 7626),
distal fragment of metapodial (BYUVP 7629), 2 first phalanges (BYUVP 7627,
LACM 123689), proximal portion of first phalanx without epiphysis (LACM
123691), partial proximal epiphysis of first phalanx (BYUVP 7638), 3 second
phalanges (LACM 123692, BYUVP 7630, 7632), 3 proximal portions of second
phalanges (BYUVP 7633, 7634, 7637), 3 partial proximal portions of second
phalanges (BYUVP 7628, 7635, 7636), 3 third phalanges (BYUVP 7639, 7641,
7642). Six sesamoids (BYUVP 7644-7649) are probably of Camelops but may
represent Bison. Phalanx measurements are listed in tables 7, 8, and 9.
Discussion--Webb (1965, 1974) recognized only four valid genera of late
Pleistocene North American camels: Titanotylopus, Camelops, Hemiauchenia
(=Tanupolama), and Paleolama (in order of decreasing size). Titanotylopus is
somewhat common and Camelops is very common in late Pleistocene assemblages
of western North America, but neither has been found in the east (Webb 1974).
Hemiauchenia is found in late Pleistocene deposits throughout the Americas
(Webb 1974) and is commonly associated with Camelops (Miller 1979). Paleolama
has only been found in Florida, Texas, and southern California in Pleistocene
deposits of North America (Miller 1976). Miller (1982) identified Camelops
and Hemiauchenia from Crystal Ball Cave.
The specimens listed above fall within the range of variation of Camelops
hesternus measurements from Rancho La Brea, southern California (Webb 1965)
and Selby and Dutton, eastern Colorado (Graham 1981). T. E. Downs (1984
personal communication) provided me with 8 first phalanx measurements of
Titanolopus sp., 21 of Camelops hesternus, and 21 of Hemiauchenia sp. from
southern California deposits. Those of Titanolopus range from 105 to 138 mm
in length with an average of 121 mm, those of Camelops hesternus range from
105 to 125 mm in length with an average of 116 mm, and those of Hemiauchenia
range from 91 to 110 mm in length with an average of 94 mm. The two complete
first phalanges from Crystal Ball Cave, both of which are of adults based on
epiphyseal fusion and bone density, measure 114 and 117 mm in length (see
table 7). Although there is some overlap in first phalanx length between
these genera, the Crystal Ball Cave specimens clearly match best with
Camelops.
Savage (1951) recognized four valid species of Camelops: C. hesternus and C.
huerfanensis, which are larger, and C. sulcatus and C. minidokae, which are
smaller; and Webb (1965), in his detailed description of Camelops, supported
this system. Based on limb bone measurements given by Savage (1951), C.
minidokae was about 14% smaller than C. hesternus. C. huerfanensis can only
be distinguished from C. hesternus and C. sulcatus can only be distinguished
from C. minidokae based on dental characters (Graham 1981, Savage 1951). Both
C. minidokae and C. sulcatus are too small to match the Crystal Ball Cave
specimens, and both are known only from pre-Wisconsinan deposits (Kurten and
Anderson 1980).
C. hesternus and C. huerfanensis are very similar and may be conspecific
(Hopkins 1955, Savage 1951). Both are known from the late Pleistocene, and
both are known from Idaho (Gazin 1935, Hopkins 1955, Hopkins et al. 1969) and
Colorado (Cragin 1892, Graham 1981). C. hesternus is the only species of
Camelops reported from Utah. A Camelops hesternus skull was recovered from a
lava tube 87 miles (140 km) east-southeast of Crystal Ball Cave (Romer 1928,
1929) and dated at 11,075 =225 Y.B.P. (Nelson and Madsen 1979). Camelops cf.
hesternus was reported from the Silver Creek fauna in north-central Utah
(Miller 1976). Camelops sp. was reported from Smith Creek Cave (Harrington
1934, Stock 1936, Miller 1979), but the only material mentioned is a right
navicular (Miller 1979), and no attempt was made to identify it to
species.
Since the Crystal Ball Cave specimens match measurements of C. hesternus by
T. E. Downs (1984 personal communication), Graham (1981), and Webb (1965),
and since C. hesternus is the only species reported from the state of Utah,
the Crystal Ball Cave specimens are referred to this species. But since the
only diagnostic character to distinguish C. hesternus from C. huerfanensis is
a dental feature not applicable to the Crystal Ball Cave specimens (Hopkins
1955, Savage 1951), C. huerfanensis cannot be positively eliminated on the
basis of these foot elements.
Material--Distal right portion of metapodial (LACM 123688), first phalanx
(LACM 123690), partial proximal portion of first phalanx (BYUVP 7640), second
phalanx (BYUVP 7631). Phalanx measurements are listed in tables 7, 8, and
9.
Discussion--Two genera of small camels are recognized from the Pleistocene of
North America: Hemiauchenia and Paleolama (Webb 1974). Based on illustrations
of Hemiauchenia (=Tanupolama) macrocephala (=stevensi) by Stock (1928) and
Paleolama mirifica by Webb (1974), the metapodials of H. macrocephala are 63%
longer but 3% transversely narrower at the distal end than those of P.
mirifica. The Crystal Ball Cave metapodial fragment is 12% transversely
narrower than the H. macrocephala specimens illustrated by Stock (1928) and
measurements from the Vallecito Creek and Ringold sites of southern
California provided by T. E. Downs (1984 personal communication). The first
phalanges from Crystal Ball Cave fall well within the range of Hemiauchenia
specimens reported by T. E. Downs (1984 personal communication), McGuire
(1980), and Schultz (1937). Nothing was available to compare the second
phalanx with, but it is from the same size of camel as the other elements.
The Crystal Ball Cave specimens clearly match the more narrow-legged
Hemiauchenia rather than the more broad-legged Paleolama.
Webb (1974) synonymized the North American genus Tanupolama with the South
American genus Hemiauchenia and recognized six valid species. Of these, only
H. macrocephala is found in the late Pleistocene of North America. H.
macrocephala represents the synonymy of a number of previously named North
American species (Webb 1974), and it is the best-known Pleistocene llama
(Kurten and Anderson 1980). Since only this species matches the age and
locality of the Crystal Ball Cave assemblage, and since the Crystal Ball Cave
specimens match specimens from other sites assigned to this species, the four
Crystal Ball Cave specimens are referred to H. macrocephala. Characters
separating this species from others of Hemiauchenia are almost entirely
dental (Webb 1974), however, and are therefore not applicable to the Crystal
Ball Cave material.
Miller (1982) reported Hemiauchenia from Crystal Ball Cave based on the same
material reported here. Miller (1979) reported ? Hemiauchenia sp. from Smith
Creek Cave based on a left cuboid, the proximal portion of a scapula, and a
juvenile metapodial. Hemiauchenia is better represented than Camelops at
Smith Creek Cave by a ratio of 3 to 1, but Camelops is better represented
than Hemiauchenia at Crystal Ball Cave by a ratio of 7 to 1. This difference
seems even more dramatic in light of the selection for smaller bones at
Crystal Ball Cave but not at Smith Creek Cave. Although this difference could
be explained by slight age differences in these faunas, human intervention,
or chance preservation, I feel it is more likely due to habitat differences
between these two genera of camels.
Kurten and Anderson (1980) stated that ". . . Hemiauchenia had a long stride
and was highly cursorial. It was a plains-dweller and probably fed primarily
on grass." About Camelops they stated: "Although primarily a grazer,
Camelops, with its long neck and legs, was probably an occasional browser."
Although these two camels are thought to have been plains-dwelling grazers,
it is interesting to speculate about their habitat differences. Webb (1974)
presented strong evidence that Hemiauchenia gave rise to the mountainous
living South American llamas. Camelops, on the other hand, probably resembled
the living dromedary camel (Kurten and Anderson, 1980) which prefers flat
plains habitats. The fact that Camelops is by far the better represented
camel at Crystal Ball Cave, located in a small outlier surrounded by a flat
valley, while Hemiauchenia is better represented at nearby Smith Creak Cave,
located in a canyon at the base of a high mountain, suggests that
Hemiauchenia preferred higher elevations and/or more rugged terrain than
Camelops.
Material--First phalanx (BYUVP 7811).
Material--Partial right dentary with P/3,/4, M/1 (BYUVP 7651) and anterior
left dentary with P/3,/4, M/1,/2 (BYUVP 7650, probably from the same
individual), partial right dentary with P/3 (BYUVP 7652), left patella (BYUVP
7934). Of 21 first and 51 second phalanges of non-camelid artiodactyls, most
compare best in size and proportions with Odocoileus.
Discussion--BYUVP 7650 and 7651 are of a juvenile and compare best in size
and degree of hypsodonty with juvenile individuals of O. hemionus. The P/4's
in these dentaries have 3 lobes rather than 2, a condition seen in juveniles
of Odocoileus but not Antilocapra. The P/3 of BYUVP 7652 is identical to
adult O. hemionus and distinctly larger and less hypsodont than A. americana.
The first and second phalanges from Crystal Ball Cave that compare best with
Odocoileus have a slightly larger mean size than those of Recent O. hemionus
living in Utah. This demonstrates that the Crystal Ball Cave specimens are of
O. hemionus rather than the smaller O. virginiana (Hall 1981), and it
suggests that deer decreased in size at the end of the Pleistocene much like
Ovis canadensis did (Harris and Mundel 1974).
Based on numbers of phalanges, Odocoileus is the best represented artiodactyl
in the Crystal Ball Cave assemblage; but Antilocapra americana is now the
dominant artiodactyl of the local fauna. Odocoileus sp. was reported at Smith
Creek Cave by Goodrich (1965), but no material was found by Miller (1979).
Mule deer now live in Smith Creek Canyon (Miller 1979) and sometimes come
down to Gandy at night to feed in cultivated fields (J. C. Bates 1984
personal communication). The replacement of Odocoileus by Antilocapra,
suggested by comparison of the Crystal Ball Cave assemblage with the living
community, shows that plant communities preferred by deer apparently moved
upward in altitude from Snake Valley to higher elevations in the Snake Range
at the close of the Pleistocene.
Material--Partial left maxilla with M1/,2/,3/ (BYUVP 7656).
Discussion--The M3/ was distinguished from Odocoileus by being very hypsodont
and having a more pointed posterior end as in Antilocapra. It is identical in
size and proportions to the largest male specimen of A. americana available
for comparison and distinctly larger than the extinct Pleistocene
antilocaprids.
Since A. americana presently lives around Gandy Mountain in small herds, it
is not surprising to find it in the assemblage. But it is not well
represented as a fossil, suggesting that Snake Valley has not always been the
treeless desert that it is now. Since Odocoileus hemionus is the dominant
artiodactyl in the fossil assemblage while Antilocapra americana is the
dominant living artiodactyl in the area, Antilocapra americana must have
become abundant in the area in Recent times at the expense of Odocoileus
hemionus.
Material--Posterior portion of lower right jaw with M/1,/2,/3 (LACM 123695)
and posterior portion of lower left jaw with M/3 (LACM 123696, probably from
the same individual), left magnum (BYUVP 7780).
Discussion--The molars of LACM 123695 and 123696 are distinctly larger and
more robust than Ovis aries and are even slightly larger than Recent Ovis
canadensis. This suggests that the jaws are Pleistocene rather than Recent in
age because Harris and Mundel (1974) demonstrated that O. canadensis became
reduced in size at the end of the Pleistocene.
Pleistocene bighorn sheep are commonly found in assemblages in the Great
Basin (Hibbard and Wright 1956, Stokes and Condie 1961). Even in historic
times they have been reported natively in the Snake Range (Durrant 1952, Hall
1946, 1981). O. canadensis was temporarily lost from the Snake Range but was
reintroduced in the middle 1900s and presently thrives in the higher
elevations (Mead et al. 1982). Shortly after this reintroduction, one young
ram lived on Gandy Mountain for several months (J. C. Bates 1983 personal
communication), but this is the only citing I know of at such a low elevation
in the area.
Ovis Canadensis is the best represented ungulate in the Smith Creek Cave
assemblage, and Oreamnos harringtoni is also well represented (Miller 1979).
No Oreamnos material has been identified from Crystal Ball Cave, and Ovis is
less represented than horse, camel, and deer. This difference between the two
assemblages is probably because wild goats and sheep are mountainous animals
and would rarely venture into Snake Valley. It may also represent the fact
that Smith Creek Cave was a shelter for humans since many Ovis fossils found
there appear butchered (Miller 1979).
Material--Right metacarpal and two first phalanges found associated (BYUVP
8300).
Discussion--These associated bones were found as float near the east entrance
of Crystal Ball Cave, and their greasy appearance suggests that they are
Recent. The length and shape of the metapodial demonstrates that it is of the
genus Ovis, and it is slightly longer than the O. aries specimens to which it
was compared but distinctly smaller than living O. canadensis. O. aries is
now a common domestic animal in the area, and many roam on Gandy Mountain
each winter (J. C. Bates 1984 personal communication).
Since this species is a Recent introduction from Europe, its presence has
little significance to this study. It does show, however, that the smaller
bones of large mammals are still being deposited in Crystal Ball Cave,
probably by woodrats since gates on the cave entrances would keep out all but
the smallest carnivores. These specimens were found just north of the east
entrance, an area where woodrats and their nests are often found.
Material--Second phalanx (BYUVP 7923), distal portion of second phalanx
(BYUVP 7924), 2 partial second phalanges (BYUVP 7925, 7926), 2 distal
portions of second phalanges (BYUVP 7921, 7922).
Discussion--These short, broad second phalanges compare best among living
species to Ovibos moschatus but are slightly longer and narrower. BYUVP 7923
is the most complete specimen, missing only one side of the distal extension.
It has a length of 42 mm, a proximal transverse width of 27 mm, and a
proximal anteroposterior width of 26 mm. BYUVP 7924 has the same proximal
measurements as BYUVP 7923, and BYUVP 7925 has a proximal anteroposterior
width of at least 26 mm. The distal ends taper in such a way that they are
hard to measure. The general shape of these second phalanges shows that they
are from an animal more closely related to Ovibos than any other living
bovid. Few phalanx measurements of Pleistocene oxen are available, but Nelson
and Madsen (1980) and Stokes and Hansen (1937) reported abundant isolated
Symbos cavifrons and Bootherium bombifrons crania from Lake Bonneville
deposits, and McGuire (1980) reported Euceratherium from a late Pleistocene
deposit in central Nevada.
Kurten and Anderson (1980) described Symbos cavifrons as being taller and
more slender than Ovibos moschatus, and this description matches the
difference between the Crystal Ball Cave specimens and Ovibos moschatus
perfectly. Bootherium is smaller than Symbos and is thought by many to
represent females or juveniles of that genus (Kurten and Anderson 1980,
Nelson and Madsen 1980). Euceratherium was larger and more heavily built than
Ovibos (Kurten and Anderson 1980), and a first phalanx illustrated by McGuire
(1980) is far too big at the distal end to match the second phalanges from
Crystal Ball Cave. So although no comparative material was available, both
the description and known range of Symbos cavifrons make the Crystal Ball
Cave specimens most referable to that species.
It is difficult to say if any other animals besides wood rats
contributed to transporting fossils into the cave. No other rodents
are known to transport bones as wood rats do. Small carnivores
could have done so, but the low abundance of carnivore fossils in
the assemblage suggests that none habitually used the cave as a
home. The small size of the original cave entrance would have
prevented the entry of any large mammals. Both the distance of the
fossils inside the cave and the low abundance of birds compared to
mammals suggests that birds did not transport any fossils in, and
this is one of the main differences between Crystal Ball Cave and
Smith Creek Cave (and most other cave deposits). Clearly no
inorganic processes such as wind, water, or gravity could have been
responsible for the fossil deposits since they are in fine dust in
an isolated part of the cave where none of these forces had a
magnitude capable of transporting bones.
Crystal Ball Cave has been accumulating fossils from at least
23,000 years ago to the present. Although some of the fossils are
Recent, the assemblage as a whole shows dramatic differences from
the present-day local fauna. The poor representation of many
mammals that currently live in the area may be due to the shift
from Neotoma cinerea to N. lepida as the wood rat that inhabited
the cave, and it also suggests that the shift to the present
climate occurred very recently in the history of the assemblage.
Brachyprotoma, Smilodon, several species of Equus, Camelops,
Hemiauchenia, and Symbos (or a closely related genus) are
represented in the assemblage, all of which are now extinct. As
mentioned earlier, there was a widespread extinction of large
mammals at the close of the Pleistocene, the cause of which is
under debate. This assemblage does not resolve that problem, but it
does demonstrate that a marked climatic shift did take place
contemporaneously with the extinctions, and this suggests to me
that the extinctions were also a result of this climatic shift.
Equally as significant as the extinctions are the shifts in species
ranges that the Crystal Ball Cave assemblage documents. The
presence of Ondatra zibethicus and Mustela cf. vison, both of which
require perennial water and are extirpated from the area, represent
the drying of Lake Bonneville and perennial streams around Gandy
Mountain. Ochotona princeps and Martes americana were extirpated
from the Snake Range without replacement but still live at high
elevations in nearby ranges. Marmota flaviventris, Cervus elaphus,
and Ovis canadensis are represented in the assemblage but now
inhabit only higher elevations in the Snake Range.
In other cases species now abundant at Gandy Mountain are
unrepresented or poorly represented in the assemblage while their
more boreal counterparts, now extirpated or rare in the area, are
well represented as fossils. Among jack rabbits, Lepus californicus
is presently the dominant species while L. townsendii, its more
boreal counterpart, is by far the better represented species in the
fossil assemblage. Among cottontails, Sylvilagus audubonii and S.
nuttallii make up the present local fauna, but only S. nuttallii,
the more northern species, is found in the assemblage. Lepus
americanus, a functional cottontail (J. A. White 1984 personal
communication) and a very boreal animal, is probably represented
but is now extirpated from the Snake Range. Neotoma lepida, the
only wood rat seen living in Crystal Ball Cave, is rare in the
assemblage while N. cinerea, its more boreal counterpart, is one of
the two most abundant fossil species. Vulpes vulpes is well
represented in the cave assemblage but extirpated from the area
while Urocyon cinereoargenteus, a more southern fox of similar
size, now inhabits the area but is not found as a fossil.
Although the fossil assemblage differs dramatically from the
present-day local fauna, it is not atypical of late Pleistocene
assemblages in the region. Figure 9 shows the location of and table
10 compares the fauna of 10 late Pleistocene-Recent cave
assemblages within 240 miles (400 km) of Crystal Ball Cave. The
most unique feature of the Crystal Ball Cave assemblage is the
presence of Brachyprotoma since it represents the first citing of
the genus from the western United States and the first recovery of
the new species herein named B. brevimala. Ondatra zibethicus was
found in Crystal Ball Cave but not at the other localities,
probably because of this cave's close proximity to Lake Bonneville.
Symbos cavifrons may be present at Crystal Ball Cave but absent
from the other assemblages for the same reason since it is most
common in Lake Bonneville deposits.
Some interesting paleoecological information can be inferred from
the differences between the Smith Creek Cave and Crystal Ball Cave
assemblages in particular since they are close geographically but
located in somewhat different habitats. Several species of
Spermophilus have been recovered from Smith Creek Cave, but large
numbers of a single species have been recovered from Crystal Ball
Cave. This can probably be attributed to the greater habitat
diversity at Smith Creek Cave, which is at the base of a high
mountain. Among camels, Hemiauchenia is better represented at Smith
Creek Cave but Camelops is better represented at Crystal Ball Cave.
This suggests that Hemiauchenia favored higher and/or more rugged
terrain than Camelops because Smith Creek Cave is located in the
main Snake Range while Crystal Ball Cave is located in an outlier
in Snake Valley. Of the non-camelid artiodactyls, Odocoileus
hemionus is the best represented in the Crystal Ball Cave
assemblage and Ovis canadensis is the best represented in the Smith
Creek Cave assemblage. Oreamnos harringtoni fossils have been found
in Smith Creek Cave but not in Crystal Ball Cave. Now Antilocapra
americana is the best represented artiodactyl in Snake Valley,
Odocoileus hemionus is the best represented artiodactyl in the
Snake Range, Ovis canadensis is found only at high elevations in
the Snake Range, and Oreamnos harringtoni is extinct. This suggests
that these four artiodactyls can be placed in the following order
of elevation preference starting at the highest: Oreamnos
harringtoni, Ovis canadensis, Odocoileus hemionus, and Antilocapra
americana. At the end of the Pleistocene, in rough terms, each of
these species moved upward in elevation to fill the habitat of the
next higher species. The one at the top went extinct; the one at
the bottom became abundant. Differences of lesser magnitude between
the Crystal Ball Cave and Smith Creek Cave assemblages must be
dealt with more carefully because they may represent slight
differences in the age of the deposits, biases in the mode of
deposition, human intervention, or chance preservation.
Identification of more material, especially at Smith Creek Cave,
could make comparison of these two assemblages a very valuable
paleoecological study.
The Crystal Ball Cave fauna, like many previously studied faunas,
shows that a dramatic climatic shift occurred at the end of the
Pleistocene and caused of many species to move northward in
latitude and upward in elevation and to become extinct. This shift
is particularly well expressed in the Crystal Ball Cave assemblage
because its close proximity to Lake Bonneville made the drying
trend very severe in the area. The Crystal Ball Cave fauna
documents the previous ranges and abundances of many taxa that
helps in reconstruction of details of the last Pleistocene ice
age.
Howard C. Stutz identified the plants, Lee F. Braithwaite the
gastropods, and Stephen L. Wood the beetle. John A. White provided
information valuable for identifying the lagomorphs. Elaine
Anderson provided information helpful in evaluating the
Brachyprotoma skull. Phillip M. Youngman provided unpublished
information and measurements on Brachyprotoma specimens he
recovered from Yukon Territory, Canada. Arthur H. Harris provided
bone measurements for several species of horses. Theodore E. Downs
gave me information on Pleistocene horses and measurements of
Pleistocene camels. Jim I. Mead identified some of the bovid
specimens and provided other helpful encouragement. Wade E. Miller,
J. Keith Rigby, Morris S. Petersen, Lehi F. Hintze, Elaine
Anderson, and Phillip M. Youngman made critical reviews of the
manuscript. Thanks is especially due my wife, Julie, for help with
collection and curation of specimens, gathering of literature, and
preparation of the manuscript.
This study was funded by grants from the National Speleological
Society and Associated Students of Brigham Young University, by a
private donation from Herbert H. Gerisch, and by Brigham Young
University research assistantships to the author. Publication costs
were paid for by the Joseph M. and Jessie K. D. Savage Endowment of
the Brigham Young University Monte L. Bean Museum and the Brigham
Young University College of Physical and Mathematical Sciences.
Anderson, E. 1968. Fauna of the Little Box Elder Cave, Converse
County, Wyoming. Univ. Colorado Stud. Earth Sci. Ser. 6:1-59.
________. 1970. Quaternary evolution of the genus Martes
(Carnivora, Mustelidae). Acta. Zool. Fennica 130:1-132.
Bjork, P. R. 1970. The carnivora of the Hagerman local fauna (late
Pliocene) of southwestern Idaho. Amer. Phil. Soc. Trans.
60(7):1-54.
Brattstrom, B. H. 1976. A Pleistocene herpetofauna from Smith Creek
Cave, Nevada. South. California Acad. Sci. Bull. 75:283-284.
Brown, B. 1908. The Connard Fissure, a Pleistocene bone deposit in
Northern Arkansas: with description of two new genera and twenty
new species of mammals. Amer. Mus. Nat. Hist. Mem. 9(4):157-208.
Brown, J. H. 1971. Mammals on mountaintops: nonequilibrium insular
biogeography. Amer. Nat. 105(945):467-478.
________. 1978. The theory of insular biogeography and the
distribution of boreal mammals. Great Basin Nat. Mem. 2:209-227.
Bryan, A. L. 1979. Smith Creek Cave. In The archaeology of Smith
Creek Canyon, Eastern Nevada. Tuohy, D. R. and D. L. Rendall (eds.)
Nevada State Mus. Anthrop. Pap. 17:162-251.
Chamberland, R. V., and D. T. Jones. 1929. A descriptive catalog of
Mollusca of Utah. Univ. Utah Biol. Ser. Bull. 1(1):1-203.
Cope, E. D. 1899. Vertebrate remains from the Port Kennedy bone
deposit. Philadelphia Acad. Nat. Sci. J. 11:193-267.
Cragin, F. W. 1892. Observations on llama remains from Colorado and
Kansas. Amer. Geol. 9:257-260.
Currey, D. R. 1982. Lake Bonneville: selected features of relevance
to neotectonic analysis. U.S. Geol. Surv. Open-File Rept.
82-1070:1-29.
Dalquest, W. W. 1964. Equus scotti from a high terrace near
Childress, Texas. Texas J. Sci. 16(3):350-358.
________. 1979. The little horses (genus Equus) of the Pleistocene
of North America. Amer. Midland Nat. 101(1):241-244.
________, and J. T. Hughes. 1965. The Pleistocene horse, Equus
conversidens. Amer. Midland Nat. 74(2):408-417.
Davies, W. E. 1960. Origin of caves in folded limestone. Nat.
Speleo. Soc. Bull. 22:5-19.
Davis, W. M. 1930. Origin of limestone caverns. Geol. Soc. Amer.
Bull. 41:475-628.
Durrant, S. D. 1952. Mammals of Utah. Univ. of Kansas Press,
Lawrence, 1-549.
________, M. R. Lee, and R. M. Hansen. 1955. Additional records and
extensions of known ranges of mammals from Utah. Univ. Kansas Mus.
Nat. Hist. Pub. 9(2):69-80.
Finley, R. B., Jr. 1958. The wood rats of Colorado: distribution
and ecology. Univ. Kansas Mus. Nat. Hist. Pub. 10(6):213-552.
Gazin, C. L. 1935. Annotated list of Pleistocene mammalia from
American Falls, Idaho. Washington Acad. Sci. J. 25(7):297-302.
________. 1936. A study of the fossil horse remains from the Upper
Pliocene of Idaho. U.S. Nat. Mus. Proc. 83(2985):281-320.
Gidley, J. W. 1900. A new species of Pleistocene horse from the
Staked Plains. Amer. Mus. Nat. Hist. Bull. 13:111-116.
________. 1903. The freshwater Tertiary of northwestern Texas,
American Museum expedition of 1899-1901. Amer. Mus. Nat. Hist.
Bull. 19:617-635.
________, and C. L. Gazin. 1938. The Pleistocene vertebrate fauna
from Cumberland Cave, Maryland. U.S. Nat. Mus. Bull. 171:1-99.
Gilbert, G. K. 1890. Lake Bonneville. U.S. Geol. Surv. Mon.
1:1-438.
Giles, E. 1960. Multivariate analysis of Pleistocene and Recent
coyotes (Canis latrans) from California. Univ. California Geol.
Sci. Pub. 36:369-390.
Goodrich, R. B. 1965. The Quaternary mammalian microfaunal
assemblage of Smith Creek Cave, Nevada. Unpublished thesis.
California State Univ., Los Angeles, 1-45.
Graham, R. W. 1981. Preliminary report on late Pleistocene
vertebrates from the Selby and Dutton Archeological/Paleontological
Sites, Yuma County, Colorado. Univ. Wyoming Contrib. Geol.
20(1):33-56.
Grayson, D. K. 1977. On the Holocene history of some northern Great
Basin lagomorphs. J. Mammal. 58(4):507-513.
________. 1983. Small mammals. In The archaeology of Monitor
Valley: 2, Gatecliff Shelter. Thomas, D. H. (ed.) Amer. Mus. Nat.
Hist. Anthrop. Pap. 59(1):99-126.
Green, D. J. 1961. Introduction to the speleology of Utah and
adjacent areas. Nat. Speleo. Soc. Salt Lake Grotto Tech. Notes
2(60):192-201.
Gruhn, R. 1961. The archaeology of Wilson Butte Cave, south-central
Idaho. Idaho State Mus. Occas. Pap. 6.
Hall, E. R. 1936. Mustelid mammals from the Pleistocene of North
America; with systematic notes on some Recent members of the genera
Mustela, Taxidea and Mephitis. In Studies of Tertiary and
Quaternary mammals of North America. Carnegie Inst. Washington
Contrib. to Paleont. 473:41-119.
________. 1946. Mammals of Nevada. Univ. California Press,
Berkeley, 1-710.
________. 1951. A synopsis of the North American lagomorpha. Univ.
Kansas Mus. Nat. Hist. Pub. 5(10):119-202.
________. 1981. The Mammals of North America, 2nd Edition. John
Wiley and Sons, New York, 1-1181.
Halliday, W. R. 1957. The caves of Gandy Mountain, an initial
reconnaissance. Nat. Speleo. Soc. Salt Lake Grotto Tech. Notes
2(38):31-37.
Handley, C. O., Jr. 1959. A revision of American bats of the genera
Euderma and Plecotus. U.S. Nat. Mus. Proc. 110(3417):95-246.
Harington, C. R. 1972. Extinct animals of Rampart Cave. Canadian
Geog. J. 85(5):178-183.
Harper, K. T., D. C. Freeman, W. K. Ostler, and L. G. Klikoff.
1978. The flora of Great Basin mountain ranges: diversity, sources,
and dispersal ecology. Great Basin Nat. Mem. 2:81-103.
Harrington, M. R. 1934. Ancient horses and ancient Men in Nevada.
Masterkey 8:165-169.
Harris, A. H., and P. Mundel. 1974. Size reduction in bighorn sheep
(Ovis canadensis) at the close of the Pleistocene. J. Mammal.
55(3):678-680.
Harris, A. H., and L. S. W. Porter. 1980. Late Pleistocene horses
of Dry Cave, Eddy County, New Mexico. J. Mammal. 61(1):46-65.
Hay, O. P. 1915. Contributions to the knowledge of the mammals of
the Pleistocene of North America. U.S. Nat. Mus. Proc.
48:515-575.
________. 1921. Descriptions of Pleistocene vertebrata, types of
specimens of which are preserved in the United States National
Museum. U.S. Nat. Mus. Proc. 59:617-638.
________. 1923. The Pleistocene of North America and its
vertebrated animals from the States east of the Mississippi River
and from the Canadian Provinces east of Longitude 95. Carnegie
Inst. Washington Pub. 322:1-499.
Heaton, T. H. 1984. Preliminary report on the Quaternary Vertebrate
fossils from Crystal Ball Cave, Millard County, Utah. Cur. Res.
1:65-67.
Hibbard, C. W. 1941. New mammals of the Rexroad Fauna from the
Upper Pliocene of Kansas. Kansas Acad. Sci. Trans. 44:265-313.
________. 1944. Abnormal tooth pattern in the lower dentition of
the jackrabbit, Lepus californicus deserticola (Mearns). J. Mammal.
25:64-66.
________. 1950. Mammals of the Rexroad Formation from Fox Canyon,
Kansas. Univ. Michigan Mus. Paleontol. Contrib. 8(6):113-192.
________. 1952. Vertebrate fossils from late Cenozoic deposits of
central Kansas. Univ. Kansas Paleontol. Contrib. 2:1-14.
________. 1954. A new Pliocene vertebrate fauna from Oklahoma.
Michigan Acad. Sci. Arts Let. Pap. 39:339-359.
________. 1955. Pleistocene vertebrates from the Upper Becerra
(Becerra Superior) Formation, Valley of Tequixquiac, Mexico, with
notes on other Pleistocene forms. Univ. Michigan Mus. Paleontol.
Contrib. 12:47-96.
________. 1963. The origin of the P/3 pattern of Sylvilagus,
Caprolagus, Oryctolagus and Lepus. J. Mammal. 44(1):1-15.
________, and D. W. Taylor. 1960. Two late Pleistocene faunas from
Southwestern Kansas. Univ. Michigan Mus. Paleontol. Contrib.
16:1-223.
________, and B. A. Wright. 1956. A Pleistocene bighorn sheep from
Arizona. J. Mammal. 37(1):105-107.
Hill, C. A. 1976. Cave minerals. The Speleo Press, Austin, Texas,
1-137.
Hopkins, M. L. 1955. Skull of a fossil camelid from American Falls
lake bed area of Idaho. J. Mammal. 36:278-282.
________, R. Bonnichsen, and D. Fortsch. 1969. The stratigraphic
position and faunal associates of Bison (Gigantobison) latifrons in
southeastern Idaho, a Progressive Report. Tebiwa 12(1):1-8.
Howard, H. 1935. A new species of eagle from a Quaternary cave
deposit in eastern Nevada. Condor 37:206-209.
________. 1952. The prehistoric avifauna of Smith Creek Cave,
Nevada, with a description of a new gigantic raptor. South.
California Acad. Sci. Bull. 51(2):50-54.
Howe, J. A. 1970. The range of variation in Equus (Plesippus)
simplicidens Cope from the Broadwater Quarries of Nebraska. J.
Paleontol. 44:958-968.
Humphrey, S. R., and T. H. Kunz. 1976. Ecology of a Pleistocene
relict, the western big-eared bat (Plecotus townsendii), in the
southern Great Plains. J. Mammal. 57(3):470-494.
Ingles, L. G. 1965. Mammals of the Pacific States. Stanford Univ.
Press, 1-506.
Jefferson, G. T. 1982. Late Pleistocene vertebrates from a Mormon
Mountain cave in southern Nevada. South. California Acad. Sci.
81(3):121-127.
Johnston, C. S. 1937. Notes on the craniometry of Equus scotti
Gidley. J. Paleontol. 11:459-461.
Kurten, B., and E. Anderson. 1972. The sediments and fauna of
Jaguar Cave: II-The fauna. Tebiwa 15(1):21-45.
________. 1980. Pleistocene Mammals of North America. Columbia
Univ. Press, New York, 1-442.
Logan, L. E. 1983. Paleoecological implications of the mammalian
fauna of Lower Sloth Cave, Guadalupe Mountains, Texas. Nat. Speleo.
Soc. Bull. 45(1):3-11.
Lundelius, E. L., Jr., R. W. Graham, E. Anderson, J. Guilday, J. A.
Holman, D. W. Steadman, and S. D. Webb. 1983. Terrestrial
vertebrate faunas. In Late-Quaternary environments of the United
States: Volume I, The late Pleistocene. Porter, S. C., (ed.) Univ.
Minnesota Press, 311-353.
________, and M. S. Stevens. 1970. Equus francisci Hay, a small
stilt-legged horse, middle Pleistocene of Texas. J. Paleontol.
44(1):148-153.
Malott, C. A. 1938. Invasion theory of cavern development. Geol.
Soc. Amer. Proc. 1937:323.
Martin, L. D., and A. M. Neuner. 1978. The end of the Pleistocene
in North America. Nebraska Acad. Sci. Trans. 6:117-126.
Martin, P. S. 1967. Prehistoric overkill. In Pleistocene
extinctions: The search for a cause. Martin, P. S., and H. E.
Wright, Jr. (eds.) Yale Univ. Press, New Haven, 75-120.
McGuire, K. R. 1980. Cave sites, faunal analysis, and big game
hunters of the Great Basin: a caution. Quat. Res. 14:263-268.
Mead, J. I., and A. M. Phillips III. 1981. The late Pleistocene and
Holocene fauna and flora of Vulture Cave, Grand Canyon, Arizona.
Southwestern Nat. 26(3):257-288.
Mead, J. I., R. S. Thompson, and T. R. Van Devender. 1982. Late
Wisconsinan and Holocene fauna from Smith Creek Canyon, Snake
Range, Nevada. San Diego Soc. Nat. Hist. Trans. 20(1):1-26.
Mehringer, P. J., Jr. 1967. The environment of extinction of the
late Pleistocene megafauna in the arid southwestern United States.
In Pleistocene extinctions: The search for a cause. Martin, P. S.,
and H. E. Wright, Jr. (eds.) Yale Univ. Press, 247-266.
Merriam, J. C. 1913. Preliminary report on the horses of Rancho La
Brea. Univ. California Pub. Dept. Geol. Bull. 7:397-418.
Mifflin, M. D., and M. M. Wheat. 1979. Pluvial lakes and estimated
pluvial climates of Nevada. Nevada Bureau Mines Geol. Bull.
94:1-57.
Miller, S. J. 1979. The archaeological fauna of four sites in Smith
Creek Canyon. In The archaeology of Smith Creek Canyon, eastern
Nevada. Tuohy, D. R., and D. L. Rendall (eds.) Nevada State Mus.
Anthrop. Pap. 17:271-329.
Miller, W. E. 1971. Pleistocene vertebrates of the Los Angeles
Basin and vicinity (exclusive of Rancho La Brea). Los Angeles Co.
Mus. Nat. Hist. Bull. 10:1-124.
________. 1976. Late Pleistocene vertebrates of the Silver Creek
local fauna from north central Utah. Great Basin Nat.
36(4):387-424.
________. 1982. Pleistocene vertebrates from the deposits of Lake
Bonneville, Utah. Nat. Geog. Res. Rept. 14:473-478.
Moore, G. W., and B. G. Nicholas. 1964. Speleology: The study of
caves. D. C. Heath and Company, Boston, 1-120.
Mooser, O., and W. W. Dalquest. 1975. Pleistocene mammals from
Aguascalientes, Central Mexico. J. Mammal. 56(4):781-820.
Mosimann, J. E., and P. S. Martin. 1975. Simulating overkill by
Paleoindians. Amer. Sci. 63:304-313.
Myers, A. J. 1969. Geology of the Alabaster Cavern Area. Oklahoma
Geol. Surv. Guidebook 15:6-16.
Nelson, M. E., and J. H. Madsen, Jr. 1979. The Hay-Romer debate:
fifty years later. Univ. Wyoming Contrib. Geol. 18(1):47-50.
________. 1980. Paleoecology of the late Pleistocene, large mammal
community in the northwestern Bonneville Basin, Utah. Geol. Soc.
Amer. Abs. Progr. 12(6):299.
Nelson, R. B. 1966. Structural development of northernmost Snake
Range, Kern Mountains, and Deep Creek Range, Nevada and Utah. Amer.
Assoc. Petrol. Geol. Bull. 50(5):921-951.
Nelson, R. S., and H. A. Semken. 1970. Paleoecological and
stratigraphic significance of the muskrat in Pleistocene deposits.
Geol. Soc. Amer. Bull. 81(12):3733-3738.
Oesch, R. D. 1967. A preliminary investigation of a Pleistocene
vertebrate fauna from Crankshaft Pit, Jefferson County, Missouri.
Nat. Speleo. Soc. Bull. 29(4):163-185.
Owen, R. 1869. On fossil remains of equines from central and south
America referable to Equus conversidens, Ow., Equus tau, Ow., and
Equus arcidens, Ow., Royal Soc. London Phil. Trans. 159:559-573.
Parmalee, P. W., and R. D. Oesch. 1972. Pleistocene and Recent
faunas from the Brynjulfson Caves, Missouri. Illinois State Mus.
Rept. Inves. 25:1-52.
________, and J. E. Guilday. 1969. Pleistocene and Recent
vertebrate faunas from Crankshaft Cave, Missouri. Illinois State
Mus. Rept. Inves. 14:1-37.
Peterson, O. A. 1926. The fossils of the Frankstown Cave, Blair
County, Pennsylvania. Ann. Carnegie Mus. 16:249-315.
Repenning, C. A. 1962. The giant ground squirrel, Paenemarmota. J.
Paleontol. 36:540-556.
Romer, A. S. 1928. A "fossil" camel recently living in Utah.
Science 68(1749):19-20.
________. 1929. A Fresh Skull of an Extinct American Camel. J.
Geol. 3:261-167.
Savage, D. E. 1951. Late Cenozoic vertebrates of the San Francisco
Bay Region. Univ. California Pub. Dept. Geol. Sci. Bull.
28:215-314.
Schultz, J. R. 1937. A late Cenozoic vertebrate fauna from the Coso
Mountains, Inyo County, California. Carnegie Inst. Washington Publ.
487(4):77-109.
Scott, W. E., W. D. McCoy, R. R. Shroba, and M. Rubin. 1983.
Reinterpretation of the exposed record of the last two cycles of
Lake Bonneville, Western United States. Quat. Res. 20:261-285.
Semken, H. A. 1966. Stratigraphy and paleontology of the McPherson
Equus Beds (Sandahl Local Fauna), McPherson County, Kansas. Univ.
Michigan Mus. Paleontol. Contrib. 20:121-178.
Skinner, M. F. 1942. The fauna of Papago Springs Cave, Arizona.
Amer. Mus. Nat. Hist. Bull. 80(6):143-220.
Smith, G. R. 1978. Biogeography of intermountain fishes. In
Intermountain biogeography: a symposium. Harper, K. T. and J. L.
Reveal (eds.) Great Basin Nat. Mem. 2:17-42.
________, W. L. Stokes, and K. F. Horn. 1968. Some late Pleistocene
fishes of Lake Bonneville. Copeia 4:807-816.
Stock, C. 1928. Tanupolama, a new genus of llama from the
Pleistocene of California. Carnegie Inst. Washington Pub.
393:29-37.
________. 1936. A new mountain goat from the Quaternary of Smith
Creek Cave, Nevada. Southern California Acad. Sci. Bull.
35(3):149-153.
________. 1963. Rancho La Brea. Los Angeles Co. Mus. Sci. Ser.
20:1-83.
Stokes, W. L., and K. C. Condie. 1961. Pleistocene bighorn sheep
from the Great Basin. J. Paleontol. 35(3):598-609.
Stokes, W. L., and G. H. Hansen. 1937. Two Pleistocene musk-oxen
from Utah. Utah Acad. Sci. Arts Let. 14:63-65.
Thomas, D. H. 1983. Large mammals. In The archaeology of Monitor
Valley: 2, Gatecliff Shelter. Thomas, D. H. (ed.) Amer. Mus. Nat.
Hist. Anthrop. Pap. 59(1):126-129.
Thompson, R. S. 1979. Late Pleistocene and Holocene packrat middens
from Smith Creek Cave, White Pine County, Nevada. In The
archaeology of Smith Creek Canyon, eastern Nevada. Tuohy, D. R.,
and D. L. Rendall (eds.) Nevada State Mus. Anthrop. Pap.
17:361-380.
________, and J. I. Mead. 1982. Late Quaternary environments and
biogeography in the Great Basin. Quat. Res. 17(1):39-55.
Valastro, S., Jr., E. M. Davis, and A. G. Varela. 1977. Univ. of
Texas Austin Radiocarbon Dates XI. Radiocarbon 19(2):280-325.
Vaughan, T. A. 1972. Mammalogy. Philadelphia: W. B. Sanders Co.,
1-463.
Webb, S. D. 1965. The osteology of Camelops. Los Angeles Co. Mus.
Sci. Bull. 1:54.
________. 1969. Extinction-origin equilibria in late Cenozoic land
mammals of North America. Evolution 23:688-702.
________. 1974. Pleistocene llamas of Florida, with a review of the
lamini. In Pleistocene mammals of Florida. Webb, S. D. (ed.) Univ.
Presses Florida, 170-213.
Wells, P. V. 1983. Paleobiogeography of montane islands in the
Great Basin since the last glaciopluvial. Ecol. Mon.
53(4):341-382.
Willoughby, D. P. 1974. The empire of Equus. A. S. Barnes and
Company, South Brunswick, 1-475.
Ziegler, A. C. 1963. Unmodified mammal and bird remains from Deer
Creek Cave, Elko County, Nevada. In Deer Creek Cave, Elko County,
Nevada. Nevada State Mus. Anthrop. Pap. 11:15-22.
Zimina, R. P., and I. P. Gerasimov. 1969. The periglacial expansion
of marmots (Marmota) in middle Europe during the Upper Pleistocene.
In Etudes sur le Quaternaire dans le Monde. Ters, M. (ed.) CNRS,
Paris, 465-472.
Figure 1 - Index map showing the location of Crystal Ball Cave and
other features of the Snake Range and Snake Valley. The stippled
area represents the extent of Lake Bonneville at the Bonneville
Level.
Figure 2 - Looking west at Gandy Mountain. The arrow marks the
location of Crystal Ball Cave.
Figure 3 - Planimetric map of Crystal Ball Cave (modified from
Halliday 1957) showing the location of fossil sites.
Figure 4 - Plot of Sylvilagus and Lepus dentaries from Crystal Ball
Cave and ranges of variation for all species of leporids presently
living in and near Utah and Nevada. Some of the measurements of
Recent specimens were made by the author from the Brigham Young
University Monte L. Bean Museum mammal collection, and some were
provided by J. A. White (1984 personal communication). The number
of Recent specimens measured were 31 of S. idahoensis, 22 of S.
nuttallii, 33 of S. audubonii, 12 of S. floridanus, 40 of L.
americanus, 36 of L. californicus, and 29 of L. townsendii. Symbols
on the plot margins represent Crystal Ball Cave specimens on which
only one of the two plotted measurements could be made.
Figure 5 - Photographs of the type specimen of Brachyprotoma
brevimala (BYUVP 7490) in palatal and right side view (X3).
Figure 6 - Plot of Equus first phalanges from Crystal Ball Cave and
ranges of variation for some late Pleistocene North American
species. The number of specimens plotted to show the range of
variation were 46 of E. conversidens, 9 of E. niobrarensis, 6 of E.
occidentalis, 6 of E. pacificus, and 2 of E. scotti. These
measurements were taken from Dalquest and Hughes (1965), Gazin
(1936), A. H. Harris (1984 personal communication), and Harris and
Porter (1980).
Figure 7 - Plot of Equus second phalanges from Crystal Ball Cave
and ranges of variation for some late Pleistocene North American
species. The number of specimens plotted to show the range of
variation were 26 of E. conversidens, 3 of E. niobrarensis, 8 of E.
occidentalis, 4 of E. pacificus, and 2 of E. scotti. These
measurements were taken from Dalquest and Hughes (1965), Gazin
(1936), A. H. Harris (1984 personal communication), and Harris and
Porter (1980).
Figure 8 - Plot of Equus third phalanges from Crystal Ball Cave and
ranges of variation for some late Pleistocene North American
species. The number of specimens plotted to show the range of
variation were 6 of E. conversidens, 5 of E. niobrarensis, 1 of E.
occidentalis, 2 of E. pacificus, and 2 of E. scotti. These
measurements were taken from Dalquest and Hughes (1965), Gazin
(1936), A. H. Harris (1984 personal communication), and Harris and
Porter (1980).
Figure 9 - Map showing the location of ten late Pleistocene cave
faunas (see table 10 for a list of the mammalian taxa recovered)
and the Silver Creek fossil site described by Miller (1976).
Table 1 - List of taxa recovered from Crystal Ball Cave.
Table 2 - Radiometric dates of bone samples from Crystal Ball Cave
provided by Geochron Laboratories, Cambridge, Massachusetts.
Table 3 - Measurements of Brachyprotoma skulls. Brigham Young
University Vertebrate Paleontology (BYUVP) 7490 is from Crystal
Ball Cave, Utah. American Museum of Natural History (AMNH) 12426
and 11772 are from Connard Fissure, Arkansas (Brown 1908, Hall
1936). U.S. National Museum (USNM) 8155 is from Cumberland Cave,
Maryland (Gidley and Gazin 1938, Hall 1936). Carnegie Museum (CM)
11057A and 20233 are from Frankstown Cave, Pennsylvania (Hall 1936,
Peterson 1926, P. M. Youngman 1984 personal communication). A skull
mislabelled Carnegie Museum (CM) 308 (here listed as Cra. Pit is
from Crankshaft Pit, Missouri (Oesch 1967, Parmalee et al. 1969).
Starred measurements are based on photos only. All measurements are
in millimeters. The coefficients of variability (C.V.) have been
multiplied by 100.
Table 4 - Measurements of Equus first phalanges from Crystal Ball
Cave. All measurements are in millimeters and parallel to the main
bone axes.
Table 5 - Measurements of Equus second phalanges from Crystal Ball
Cave. All measurements are in millimeters and parallel to the main
bone axes.
Table 6 - Measurements of Equus third phalanges from Crystal Ball
Cave. All measurements are in millimeters and parallel to the main
bone axes.
Table 7 - Measurements of first phalanges of Camelops cf. hesternus
(C) and Hemiauchenia cf. macrocephala (H) from Crystal Ball Cave.
All measurements are in millimeters and parallel to the main bone
axes.
Table 8 - Measurements of second phalanges of Camelops cf.
hesternus (H) and Hemiauchenia cf. macrocephala (C) from Crystal
Ball Cave. All measurements are in millimeters and parallel to the
main bone axes.
Table 9 - Measurements of third phalanges of Camelops cf. hesternus
from Crystal Ball Cave. All measurements are in millimeters and
parallel to the main bone axes.
Table 10 - Comparison of the Crystal Ball Cave faunawith nine other
Late Pleistocene/Early Holocene mammaliancave faunas located within
240 miles (400 km) of Crystal Ball Cave. The locations of these
caves are shown in figure 9.
Division Tracheophyta
Class Gymnospermae
Family Ephedraceae
Ephedra cf. viridis
Family Asteraceae
Chrysothamnus sp.
Opuntia sp.
Symphoricarpos cf. longiflorus
cf. Elymus
Phylum Mollusca
Class Gastropoda
Order Pulmonata
Family Helicidae
Oreohelix strigosa
Class Crustacea
Order Isopoda
Family ? Armadillidae
Order Coleoptera
Family Scarabaeidae
Aphodius distinctus
Class Osteichthyes
Infraclass Teleosti
Order Squamata
Order Insectivora
Family Soricidae
Sorex sp.
Family Vespertilionidae
Myotis sp.
small unicusp premolars following the incisor, as opposed to one or none in
all other vespertilionids. Dentaries of Myotis and Plecotus are virtually
identical, both having the dental formula of I/3, C/1, P/3, P/3 and similar
size and proportions, and no character could be found to separate them.
Dentaries of Lasionycteris and Pizonyx also share this tooth formula but are
considerably larger. Myotis has not been reported living in Crystal Ball
Cave, but M. lucifugus, M. evotis, M. thysanodes, M. volans, and M. subulatus
are all found in the region (Hall 1981). Little work has been done to
separate species of Myotis dentally, and I was unable to find any species
variation that was greater than individual variation.
Family Ochotonidae
Ochotona princeps
Sylvilagus idahoensis
Family Sciuridae
Marmota flaviventris
Material--Right dentary with P/4, M/1,/2 (BYUVP 6812), 3 right
Thomomys umbrinus
Perognathus cf. formosus
Peromyscus maniculatus
Family Canidae
Canis cf. latrans
Material--Partial right M1/ (BYUVP 7455), left P/1 (BYUVP
7457),
Mustela cf. frenata
Smilodon cf. fatalis
Family Equidae
Equus cf. scotti
Family Camelidae
Camelops cf. hesternus
cf. Cervus elaphus
Discussion--Several cervid phalanges from Crystal Ball Cave are intermediate
in size between Cervus and Odocoileus. BYUVP 7811 (60.2 mm long) is the
largest of these and is much closer in size to Cervus. In comparison with the
others it is distinctly larger and more robust, yet high bone porosity
suggests that it is of a sub-adult. Navahoceros fricki is another late
Pleistocene cervid found as close to Utah as Arizona and Wyoming, and its
size is intermediate between Odocoileus and Cervus (Kurten and Anderson
1980). No character has been described to differentiate phalanges of
Navahoceros and Cervus, and no comparative material of Navahoceros was
available to the author. C. elaphus was recovered from Smith Creek Cave
(Miller 1979) and has been reported living in the Snake Range in Recent times
(Hall 1981), so the phalanx is referred to this species.
Antilocapra americana
The Crystal Ball Cave assemblage is the first late Wisconsinan
fauna reported from the state of Utah and represents the closest
known terrestrial fossil deposit to Lake Bonneville. The assemblage
differs from most other cave faunas by having its fossils far
inside the cave where man and birds probably had no influence on
what was deposited. As a result, the assemblage is better than
average in representing the proportions of animals that lived in
the area, but there are some obvious biases. Neotoma, always an
animal of low density, was the second most abundant genus in the
assemblage simply because it is one of the few animals that lives
in the cave. But other than cave-dwelling species, the assemblage
probably gives a fairly good record of the abundance of most
groups, at least those which lived in the immediate vicinity of the
cave. The assemblage, for example, contains a ratio of small
mammals to large mammals and carnivores to herbivores that might be
expected in a living community. One very strong bias is the size of
bones in the assemblage that I have attributed to the limit of bone
size that a wood rat can carry. Bones of large mammals were brought
in after the carcasses deteriorated, as evidenced by the presence
of only small isolated elements. This bias tends to make large
species less represented in the assemblage than in the living
community and very large species unrepresented. Proboscidian
fossils are common in Lake Bonneville deposits (Nelson and Madsen
1980) but are unrepresented at Crystal Ball Cave, probably because
there was no means to transport such large bones inside.
This study was supervised by Wade E. Miller who helped in
collecting and identifying specimens and preparing the manuscript.
His insistence that every identification be backed by thorough
research and explanation has made a lasting impression on me.
Thanks is also due Kenneth L. Stadtman and Clyde L. Pritchett for
providing comparative specimens and help in identification. Jerald
C. and Marlene Bates of Gandy allowed me access to Crystal Ball
Cave on many occasions and provided helpful information on the
history and original condition of the cave, as well as the mammals
that currently live in the immediate area. The Los Angeles County
Museum generously loaned me the Crystal Ball Cave specimens in
their possession so they could be included in this study.
Timothy H. Heaton:
E-mail,
Home page,
Phone (605) 677-6122, FAX (605) 677-6121