Anthony D Barnosky

University of California, Berkeley

This chapter has been compiled from information provided by the authors of chapters in part 2.

At least 127 species are known as fossils from the 26 localities in Porcupine Cave (2 amphibians, 4 reptiles, 48 birds, and 73 mammals). More than 20,000 specimens have been studied in detail. The fauna includes two species that are newly recognized and extinct, Brachylagus coloradoensis (Colorado pygmy cottontail) and? Cynomys andersoni (prairie dog), and two more that suggest that new species should be formally recognized when more material becomes available, Mustela sp. A (extinct marten) and Martes sp. A (extinct mustelid). Twenty-eight extant species (20 birds and 8 mammals) make their earliest North American appearance in Porcupine Cave deposits: Falcipennis canadensis (Spruce Grouse), Centrocercus urophasianus (Greater Sage Grouse), Dendrograpus cf. D. obscurus (Blue Grouse), Numenius madagascariensis or N. arquata (Far Eastern or Eurasian Curlew), Phalaropus cf. P. lo-batus (Red-necked Phalarope), Nyctea scandiaca (Snowy Owl), Pica hudsonia (Black-billed Magpie), Gymnorhinus cyanocephalis (Pinyon Jay), Corvus corax (Common Raven), Eremophila alpestris (Horned Lark), Tachycineta cf. T. bicolor (Tree Swallow), Sitta carolinensis (White-breasted Nuthatch), Spizella breweri (Brewer's Sparrow), Spizella cf. S. passerina (Chipping Sparrow), Zonotrichea leucophrys (White-crowned Sparrow), Chondestes grammacus (Lark Sparrow), Junco hyemalis (Dark-Eyed Junco), Leucosticte tephrocotis (Gray-crowned Rosy-finch), Leucosticte artrata (Black Rosy-finch), Carpodacus cassinii (Cas-sin's Finch), Mustela nigripes (black-footed ferret), Spermo-philus cf. S. elegans (Wyoming ground squirrel), Lemmiscus curtatus (sagebrush vole), Neotoma cinerea (bushy-tailed wood rat), Neotoma mexicana (Mexican wood rat), Neotoma floridana (eastern wood rat), Neotoma micropus (southern plains wood rat), and Neotoma stephensi (Stephens' wood rat). Sylvilagus audubonii (desert cottontail) and Sylvilagus nuttalli (Nuttall's cottontail) may also have their earliest records in Porcupine

Cave, a possibility regarded as tentative given the difficulty in distinguishing the dental remains of these species (chapter 15).

Most genera represented by the fossils are still extant, but at the species level an admixture of many extinct with extant species predominates. The large number of extinct species is no surprise, given the antiquity of the deposits. Among extinct species, the cave yields the earliest North American record for Oreamnos harringtoni (extinct mountain goat), as well as the earliest records in mountainous western America for Brachy-protoma obtusata (short-faced skunk), Gulo cf. G. schlosseri (Schlosser's wolverine), Martes diluviana (extinct fisher), and Miracinonyx cf. M. inexpectatus (Irvingtonian cheetah). Two taxa exhibit their youngest geological record in Porcupine Cave: Hypolagus (rabbit) and Phenacomys gryci (Gryci's vole).

Most of the fossils date from the Irvingtonian North American Land Mammal Age (NALMA), especially in the range of about 600 Ka to perhaps as old as 1 Ma (chapters 2, 7). However, at least two localities in the cave, Mark's Sink and Fissure Fill A, may be considerably older, potentially reaching into the Blancan NALMA, as suggested by arvicoline rodents (chapter 19) and horses (chapter 20), respectively. The Blancan-Irvingtonian boundary dates to somewhere between 1.3 and 1.5 Ma (Bell et al., in press).

This chapter presents summary species lists for each locality, and when possible provides estimates of number of identifiable specimens (NISP) and minimum numbers of individuals (MNI) for each species at each locality. These lists make clear that the most abundant fossils are those of small mammals, particularly rodents such as ground squirrels, wood rats, and voles, which are represented by thousands of specimens each. Other rodents and rabbits are commonly represented by hundreds of specimens per species. Insectivores, carnivores, and ungulates are much less common and typically are known by tens of specimens. Each amphibian, reptile, and bird species generally is represented by fewer than 10 specimens.

MNI NISP

MNI NISP

Anura (frog or toad)

Amphibia

Aves

Anatidae, indeterminate Buteo sp. (Hawk)

Corvus brachyrhynchos (American Crow) Corvus corax (Common Raven)

Mammalia t Mylodontidae (ground sloth) Soricidae cf. Sorex sp. (shrew) Ochotonidae

Ochotona cf. O. princeps (pika) Leporidae Lepus sp. (hare or jackrabbit) Sylvilagus sp. (cottontail rabbit) Leporid (rabbit or hare) t Aztlanolagus sp. (Aztlan rabbit) Brachylagus coloradoensis (Colorado pygmy cottontail) cf. Brachylagus (pygmy cottontail) Sciuridae Marmota sp. (marmot) Spermophilus sp. (species indeterminate)

(ground squirrel) Spermophilus lateralis (golden-mantled ground squirrel) Spermophilus cf. S. elegans (Wyoming ground squirrel) t Cynomys andersoni new sp.

(prairie dog) Cynomys sp. (prairie dog) Geomyidae

Thomomys sp. (pocket gopher) Muridae

Neotoma sp. (wood rat) Peromyscus sp. (deer mouse) Arvicolinae t Allophaiomys pliocaenicus (vole) t Mimomys virginianus (Virginia mimomys)

7 14

t Phenacomys gryci (Gryci's vole) Microtus 5T (vole)

t Mictomys kansasensis/meltoni (extinct bog lemming) Ondatra sp. (muskrat) Erethizontidae

Erethizon sp. (porcupine) Mustelidae t Martes diluviana (extinct fisher) Mustela frenata (long-tailed weasel) Mustela nigripes (black-footed ferret) t Mustela species A (extinct mustelid) cf. Lutra (river otter) Taxidea taxus (badger) Spilogaleputorius (spotted skunk) t Brachyprotoma obtusata (short-faced skunk)

Mephitis mephitis (striped skunk) Canidae Canis latrans (coyote) t Canis edwardii (Edward's wolf) Canis sp. (small canid) Vulpes vulpes (red fox) Felidae Lynx rufus (bobcat) t Miracinonyx cf. M. inexpectatus (Irvingtonian cheetah) Tayassuidae t Platygonus sp. (peccary) Cervidae

Odocoileus sp. (deer) Antilocapridae

Antilocapridae, genus and species indeterminate Bovidae

Ovis sp. (bighorn sheep) Ovibovini, genus and species indeterminate Equidae t Equus sp. (large) (horse) t Equus sp. (small) (horse)

15 1

122 45

notes: x, taxa present, but estimates for MNI and NISP are unavailable; t, extinct species.

Only the Pit (CM 1925 / UCMP V93173) and Badger Room (CM 1928 / DMNH 942 / UCMP V93176) are considered completed excavations and have had nearly all specimens identified. For this reason, the paleoecological, evolutionary, and paleoenvironmental conclusions presented in part 3 focus primarily on those two localities.

All of the other localities should be regarded as incompletely sampled, or, as in the case of the DMNH Velvet Room localities, well sampled but with many of the specimens remaining to be identified. Absence of a species in the faunal lists for these localities does not necessarily imply that the species is not there; much unidentified material awaits analy table 10.2

Faunal Lists for Badger Dome, Come-A-Long Room, Cramped Quarters, Crystal Room, and Damp Room

MNI NISP MNI NISP

Badger Dome

Crystal Room

Mammalia

Mammalia

Mustelidae

Arvicolinae

Taxidea taxus (badger)

1

4

t Microtus paroperarius (vole)

1

1

Microtus 5T (vole)

1

1

Come-A-Long Room

Mustelidae

Mammalia

Taxidea taxus (badger)

1

Spermophilus cf. S. elegans (Wyoming

Canidae t Canis edwardii (Edward's wolf) Felidae

Lynx rufus (bobcat) Camelidae t Camelops sp. (camel) Antilocapridae

1

2

ground squirrel) Antilocapridae

1

1

1

3

Antilocapridae, genus and species indeterminate

1

1

1

1

Cramped Quarters

Antilocapridae, genus and species indeterminate Bovidae

1

1

Mammalia

Felidae

t Oreamnos harringtoni (extinct mountain

Lynx rufus (bobcat)

1

1

goat)

1

1

Equidae

t Equus sp. (large) (horse)

1

1

Damp Room

Unidentified specimens

x

x

notes: x, estimates for MNI and NISP are unavailable; t, extinct species.

notes: x, estimates for MNI and NISP are unavailable; t, extinct species.

sis. For these cursorily or unanalyzed localities, the species lists, as well as the NISP and MNI estimates, are subject to change as future workers examine the specimens. They should be interpreted in light of the excavation information provided in chapter 2 and used primarily as a guide for where future efforts might most profitably be focused. The NISP and MNI of lagomorphs in the Badger Room are inflated relative to those of lagomorphs at other localities because postcranial bones, cranial material, and teeth were all identified in the Badger Room, whereas only cranial and dental fossils were identified from other localities. Comparisons between the Badger Room and Pit localities (chapters 7, 22, 23) take this into account.

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