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Use of Mammalian Remains in Interpreting Quaternary Environments. Functional morphology is absolutely critical!. The Woolly Mammoth, Mammuthus primigenius , is one of the archetypical mammals of the Pleistocene megafauna. But it wasn't the ONLY North American elephant!.
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Use of Mammalian Remains in Interpreting Quaternary Environments Functional morphology is absolutely critical!
The Woolly Mammoth, Mammuthus primigenius, is one of the archetypical mammals of the Pleistocene megafauna. But it wasn't the ONLY North American elephant!
Then there was the American Mastodon, Mammut americanum. Just another elephant you say ?
Put 'em side by side and they look no more alike than a collie and a pit bull! (These lineages diverged in the Oligocene!) This is a major ecological difference - a grazer (Mammuthus) and a browser (Mamut). They occupied different habitats entirely. How do we know?
Look at the teeth! At right, a pair of mastodon molars - below, mammoth. These are lineages that diverged in the Oligocene, over 20 million years ago ... Mammuthus exilis Mammuthus columbi Mammuthus primigenius
Dima, a juvenile mammoth carcass found in Siberia ca. 1974
Archidiskodon meridionalis, the giant Siberian mammoth of the middle Pleistocene Mammuthus columbi, the Columbian mammoth, of North America
Family structure is probably reasonable - but how could they all be fed in the Arctic?
The saiga, the Mongolian steppe antelope, was also a member of the circumpolar Pleistocene mammal fauna. Aren't those tiny feet cute?
Aren't those tiny feet cute? Compare these to the hooves of the caribou (a.k.a. reindeer) that lives in the same regions today! Saiga couldn't survive in today's soft, wet tundra.
Smilodon, the sabre-toothed cat, is another Pleistocene animal of near-mythic proportions. This predator is the official state fossil of California.
Carnivore teeth tend to be high-crowned and three-lobe pointed, like these examples. Above, a cave bear from Siberia. Upper right, a shrew mandible fragment. At right, an extinct wild dog mandible.
Wild horses, believed to have been closely related to the Siberian wild ass (Equus przewalskii, above) were widespread and highly varied across North America. Teeth at UR are from Florida, the one to the right is Alaskan.
The woolly rhinoceros was an Old World Pleistocene form that made it into central Siberia, but never quite made it farther east to get into North America.
MOST important, most abundant, and most informative, are actually the teeth of microtine rodents - the mice, voles, lemmings, and other tiny critters. These are the most rapidly evolving group of organisms on the planet, the most widespread of mammals, and the most abundant in terms of numbers per any given area (or volume of sediment!)