If I Could Live During the Pleistocene Part XII–My Mammal Checklist

I have a recurring fantasy (and it’s an ongoing irregular series on this blog) that I’ve found a time tunnel allowing me to travel back and forth from the present day to 36,000 years BP.  The site at the other end of the tunnel is located at what today is Elbert County, Georgia about 1 mile north of the Broad River and 2 miles west of the Savannah River, and at this location I’ve established a homestead.  I produce all my own food here, growing vegetables and fruits and raising milk cows, geese, chickens, and bees; so I rarely need to return to the present day for supplies.

Location of my imaginary Pleistocene homestead, 36,000 BP.

Varied pristine environments untouched by man offered many different habitats for wildlife here.  (Homo sapiens probably didn’t reach North America until 20,000 BP at the earliest.)  Interstadial climatic conditions prevailed 36,000 years ago–a warm spell between Ice Ages.  Oak trees predominated over pine, a situation that was reversed during cold stadials.  In the vicinity of my imaginary homestead there are moist slope forests consisting of beech, hickory, a variety of oaks, and walnut; open old growth woodlands composed of black oaks, red oaks, jack pine, and shortleaf pine; dry chestnut ridges; natural meadows; canebrakes; freshwater marshes; clear fish-filled rivers with lots of rocky shoals; creek bottoms laced with beaver ponds; brushy areas where storm-downed  trees resulted in open canopies; and recently burned over areas with dense stands of young trees.

In my imaginary life as a Pleistocene homesteader, I’ve surveyed the wildlife and produced a checklist of mammal species that I’ve collected or observed. The large animals are easy to see and catalogue, but the smaller ones are harder to collect and identify.  At night I set mist nets to capture bats–a more humane method than the one Frances Harper used in the early 20th century when he surveyed bats in the Okefenokee by smacking them down with a fishing rod.  I used live traps for small ground dwelling mammals.

Mist net for catching bats.

H.P Sherman trap for catching small mammals alive.

Below is a checklist of the mammals that I would probably collect or observe in this region during this time period.  I put question marks by the species that I might or might not find.  The fossil record in east central Georgia is very meager, and even in the surrounding states, it’s incomplete.  This checklist is simply an educated guess.

1. Opossum–Didelphis virginianus: Probably less common than today because of the abundance of mid to large-sized carnivores.

2. Southeastern shrew–Sorex longirostis

3. ?Smoky shrew?–Sorex fumeus

4. ?Longtail shrew?–S. disper

5. ?Pygmy shrew?–Microsorex hiyi: None of these 3 species of shrew are known in this region today, but they are known to have had wider ranges during some climatic phases of the Pleistocene.  At least one of these species might have occurred in east central Georgia then.

6. Least shrew–Cryptotis parva

7. Short-tailed shrew–Blarina brevicauda

8.  Star-nosed mole–Condylura cristata

9. Eastern mole–Scalopus aquaticus

10. ?Vampire bat?–Desmodus stocki–Lived in Georgia during warm interglacials.  Climate may have been too cold 36,000 years ago here.

11. Small footed myotis–Myotis leibi

12. Indiana myotis–M. sodalis

13. Gray myotis–M. grisecens

14. Little brown myotis–M. lucifruga

15. Southeastern myotis–M.austrariparius

16. ?Silver haired bat?–Lasionycteris noctivagus

17. Eastern pipistrelle–Pipistrellus subflavus

18. Big brown bat–Eptesicus fuscus

19. Hoary bat–Lasiurius cinereus

20. Red bat–L. borealis

21. Yellow bat–L. intermedius

22. Evening bat–Nycterius humeralis

23. Rafinesque’s big eared bat–Plectocus rafinesquis

23. Brazilian free-tailed bat–Tadarida brasiliensis: This species no longer occurs in this region.  It had a wider range before the Last Glacial Maximum and has yet to recolonize much of its former range.  It may do so in the future.

24. Northern pampathere–Holmesina septentrionalis: A 300 pound grass-eating armadillo that probably survived cold spells by digging underground burrows.

25. Beautiful armadillo–Dasypus bellus: As I’ve speculated in a previous blog entry (https://markgelbart.wordpress.com/2012/08/19/is-the-9-banded-armadillo-dasypus-novemcinctus-a-dwarf-mutation-of-the-pleistocene-species-dasypus-bellus/), I hypothesize the modern 9 banded armadillo is a dwarf mutation of this supposedly extinct species.

26. Jefferson’s ground sloth–Megalonyx jeffersonii

27. Harlan’s ground sloth–Glossotherium harlani: Jefferson’s prefered woodlands; Harlan’s preferred grasslands.

28. Fisher–Martes pennanti: I think this species would have a wider modern range, if not for its high quality fur.  Fisher skeletel material has  been found in the fossil and archaeological record of north Georgia.

29. Long tailed weasel–Mustela frenata

30. ?Badger?–Taxidea taxus:  There may or may not have been enough pure grassland in this region then to support a population of this prairie-loving  species.

31. Mink–Mustela vison

32. River otter–Lutra canadensis

33. Spotted skunk–Mephitis putorius

34. Striped skunk–Mephitis mephitis

35. Hog-nosed skunk–Conepatus leuconotus: This is another species that had a wider range during the Pleistocene.  The desert grassland habitat it requires completely disappeared in this region during the Holocene.

36. Coyote–Canis latrans

37. Dire wolf–Canis dirus: Probably one of the most common large carnivores in the region then.

38. ?Dhole?–Cuon alpinus: Dhole fossils have only been found at 2 sites in North America in Mexico and Alaska.  This species may have been more widespread than the fossil record indicates. See https://markgelbart.wordpress.com/2011/06/01/did-the-dhole-cuon-alpinus-range-into-southeastern-north-america-during-the-pleistocene/

39. Gray fox–Urocyon cineaoargenteus

40. Red fox–Vulpes vulpes

41. Raccoon-Procyon lotor

42. Florida spectacled bear–Tremarctos floridanus: This species likely didn’t hibernate and required year round forage.  It may have been as common as the black bear in Florida and the coastal plain of  the south where winters were especially mild but less so in the piedmont and mountains.

43. Giant short-faced bear–Arctodus simus: Probably a wide ranging occasional animal that would have been scary to encounter.  A kleptoscavenger that drove other predators from their kills.

44. Black bear–Ursus americanus: Probably very common in east central Georgia then.  Pleistocene black bears grew as large as grizzlies, and I hypothesize were more aggressive than they are today thanks to the big cats below.

45. Saber-tooth–Smilodon fatalis: I would have loved to have seen one of these alive and in action.

46. Scimitar-tooth–Dinobastis serum: Ditto.

47. ?American lion?–Panthera atrox: A denizen of open grassland habitat.  Unknown whether enough grassland existed to support this species in east central Georgia 36,000 BP, but it did colonize Florida during the LGM when drier conditions fostered more grassland.

48. Jaguar–Panthera onca: Probably the most common big cat in this region then.

49. Cougar–Puma concolor

50.? Margay?–Leopardus amnicola: An arboreal cat that was common and widespread in southeastern North America during the Sangamonian Interglacial.  It’s difficult to determine whether it still survived in the region 36,000 BP.  Winters may have gotten too cold by then.

51. Bobcat–Lynx rufus

52. Woodchuck–Marmota monax

53. ?13-lined ground squirrel?–Spermophilus tridecemlineatus: Difficult to determine if there were enough relic grasslands to support a population of this species in this region during this climatic phase.

54. Eastern chipmunk–Tamias striatus

55. Giant chipmunk–Tamias aristus: Fossils of this species have been found at sites dating to the Sangamonian Interglacial.  It may not have become extinct until the Last Glacial Maximum.  I hypothesize it was a year round forager, unlike its smaller cousin which hibernates. See https://markgelbart.wordpress.com/2011/01/20/tamias-aristus-the-extinct-kicked-up-version-of-the-eastern-chipmunk/

56. Fox squirrel–Scirius niger

57. Gray squirrel–Scirius carolinensis

58. Red squirrel–Tamiascirius hudsonicus

59. Southern flying squirrel–Glaucomys volans

60. Eastern pocket gopher–Thomomys orientalis

61. Southeastern pocket gopher–Geomys pinetus

62. Giant beaver–Casteroides dilophidus: Giant beavers favored treeless marshes, but may have occasionally built dams.  Modern beavers create habitat favorable to giant beavers by felling lots of trees and the 2 species did not compete as some scientists erroneously claim.  They ate different foods.

63. Beaver–Castor canadensis

64. Rice rat–Oryxomys palustris

65. Eastern harvest mouse–Reithrodontomys humulis

66. Deer mouse–Peromyscus manisculatus

67. Old field mouse–P. polionatus

68. White-footed mouse–P. leucopus

69. Cotton mouse–P. gossypinus

70. Golden mouse–Ochrotomy nuttali

71. Cotton rat–Sigmodon hispidus

72. Red-backed vole–Clethritonomy gapperi: No longer occurs this far south.

73. Meadow vole–Microtus pennsylvanius

74. Pine vole–M. pinetorum

75. ?Prairie vole?–M. ochrogaster

76. ?Florida muskrat?–Neofiber alleni: This species formerly had a much wider range.  They require year round green vegetation.  Difficult to determine exactly when they disappeared from east central Georgia.

77. Muskrat–Ondatra zibethicus

78. Southern bog lemming–Synaptomys cooperi

79. Meadow jumping mouse–Zapus hudsonicus

80. Porcupine–Erethizon dorsatum: Had a wider range during the Pleistocene.  Archaeological evidence suggests Indians overhunted them in the southeast.

81. Capybara–Hydrochoerus holmesi: 2 species of capybaras lived on the coastal plain of Georgia during the Pleistocene.  It’s unknown exactly how far inland they ranged. They favor grassy flooded marshes alongside rivers.

82. Eastern cottontail–Sylvilagus floridanus

83. Swamp rabbit–S. aquaticus

84. Horse–Equus ferus

85. Half-ass–Equus scotti

86. Tapir–Tapirus veroensis

87. Long-nosed peccary–Mylohyus nasatus: Probably one of the most common large mammals in east central Georgia then and would be common table fair for a Pleistocene homesteader.

88. Flat-headed peccary–Platygonnus compressus

89. Large-headed llama–Hemiauchenia macrocephala

90. Stout-legged llama–Paleolama mirifica

91. White-tailed deer–Odocoileus virginianus: Probably at least as common then as today and an important part of my diet at my Pleistocene homestead.

92. ?Caribou?–Rangifer tarandus: Fossils of this species dating to the LGM have been found as far south as Charleston, S.C.  There were probably large herds of caribou seasonally migrating just south of the glacial margin which at the time was near the Canadian border.  Some of these herds evidentally broke off and wandered south.

93. ?Stag-moose?–Cervalces scotti: May have been another rare straggler that was more common farther north.

94. ?Elk?–Cervus elephus: Occurred in central Georgia as recently as the 18th century.  Genetic evidence suggests elk didn’t cross the Bering land bridge until ~15,000 years BP, but perhaps a different lineage occurred here then.

95. ?Helmeted muskox?–Bootherium bombifrons: Colonized Louisiana and Mississippi during the LGM, but fossils are unknown this far southeast. See https://markgelbart.wordpress.com/2011/07/27/the-south-central-salient-of-the-helmeted-musk-ox-ovibos-cavifrons-or-bootherium-bombifrons/

96. Long-horned bison–Bison latifrons: Probably fairly common here then.

97. Mastodon–Mammut americanus: Were either seasonal or year round residents here.

98. Columbian mammoth–Mammuthus colombi: Ditto.

99. ?Gompothere?–Cuvieronius tropicalis: Another elephant-like mammal that lived in the southeast.  Climate may have become too cold for this species in this region by 36,000 years BP.

100. 9-banded armadillo–Dasypus novemcitus: Genetic evidence suggests it co-occurred with the beautiful armadillo.

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