Ecological Dynamics on Yellowstone's Northern Range (2002) / Chapter Skim
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Appendix A: Understanding the Past
Appendix A: Understanding the Past
Pages 168-176
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From page 168... ...
in a regional perspective for the late Quaternary, especially for taxa that occur throughout the surrounding area. Mammal faunas from these sites date from the latest Pleistocene (20,000 to 10,000 years before present tYBP]
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From page 169... ...
As the climate began to warm about 14,000 years ago and glaciers recedednorthward and higher, so did some of the boreal mammalian fauna. The collared lemming that today lives on the tundra in Alaska and Canada was one of the first mammals to be extirpated from the surrounding areas and probably the GYE, having vacated the contiguous northwestern United States by at least 10,000 YBP (Faunmap Working Group ~994~.
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From page 170... ...
The sporadic presence of this species in the cave record may indicate the occurrence of more tall grass habitat in the vicinity of the cave at certain periods in the past. Although general faunal composition has been relatively stable, relative frequencies of environmentally sensitive species fluctuated through time and appeared to correspond with climatic events in the late Holocene.
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From page 171... ...
Also, an assemblage of bones from a pit cave, which acts as a natural trap, is quite different from that of a cave with a horizontal entrance, which permits both entrance and egress (Brain 19811. The behavior of animals is also important in the formation of bone accumulations.
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From page 172... ...
The ability to identify skeletal elements to species or even generic levels varies with the taxon and the experience of the faunal analyst. Most of the skeletal elements of the ungulates should be readily identifiable, but there is a
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From page 173... ...
with similar histories of accumulation. A series of late Quaternary sites from the Pryor Mountains of Montana clearly illustrate the problems of various accumulation histories and how they can influence faunal samples and bone counts.
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From page 174... ...
The main difference between the bone assemblages from the two caves is in the abundance of large mammal remains. The assemblage from Shield Trap is primarily composed of bison bones, whereas False Cougar Cave contains small mammal remains (rabbit to marmot size and smaller)
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From page 175... ...
concluded that these proportions were quite different from the proportions of the ungulate species in modern populations. For the Dead Indian Creek site, Kay did not explicitly explain how he treated the sample, but again it appears that he calculated MNIs for the various ungulate species for the entire site and then compared proportions.
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From page 176... ...
Also, grouping of data, as done by Kay (1990) by combining different stratigraphic units within sites, probably mixes various accumulation pathways for these stratigraphic levels, which again would significantly bias the frequency distributions.
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