Mammuthus Merdjonals

mammuthus columbi islands. Its ancestors, probably the European elephant E. namadicus, migrated out of Africa in the Early Pleistocene and spread west into central Europe and east to India and China, and even reached Japan.

During the lower sea-levels of the glacial periods, this elephant was able to reach Malta, Cyprus, Crete and Sardinia. With the rise of sea level as the glaciers melted in the interglacial periods, these areas became isolated as islands in the Mediterranean sea. In this isolation arose the dwarf form E. falco-neri. Similar dwarf elephants arose on the Celebes Islands in Southeast Asia.

On islands such as these, natural selection would favor animals that made best use of smaller quantities of food, and dwarf varieties and species would evolve. A modern equivalent is the small Shetland ponies that have developed on the northern Scottish islands. There is a possible dinosaurian example, also, in the dwarf ankylosaur Struthiosaurus (pp. 158-163). The experience of very small animals such as rodents, however, is the exact opposite: rodents on the Mediterranean islands were often larger than elsewhere. In the absence of natural predators, there was little need to maintain a small and slender structure that could swiftly take refuge in holes and crevices (see pp. 282-285).

name: Mammuthus meridionalis time: Early Pleistocene locality: Europe (Spain) size: Up to 15 ft/4.5 m high

The mammoths were a wide-ranging group of largely cold-adapted animals that radiated from Africa to Eurasia and North America in the Early Pleistocene.

M. meridionalis was one of the first of the mammoths, evolving in open woodlands in southern Europe, where the climates were not severe, around 2 mil lion years ago. Its ancestors probably came from farther east, or from Africa.

M. meridionalis resembled the modern Indian elephant but had much larger tusks. It may have been the ancestor of a number of more-specialized mammoth-s, including the European M. primi-genius (below) and the North American M. imperator.

name: Mammuthus trogontherii time: Middle Pleistocene locality: Europe (England,

Germany) size: 15 ft/4.5 m high M. trogontherii was the steppe mammoth. It lived in the middle Pleistocene in central Europe, in much colder conditions than its ancestors, and was probably the first to develop the hairy coat that is the familiar feature of the mammoth group. It probably roamed in herds across the cold grasslands and ate the coarse grasses that grew there.

M. trogontherii was one of the largest of the mammoths. The spiral tusks, which were thicker in the males than in the females, were very long, some measuring about 17 ft/5.2 m.

name: Mammuthus columbi time: Late Pleistocene locality: North America (Carolina,

Georgia, Louisiana, Florida) size: 12 ft/3.7 m high M. columbi was one of the American mammoths which migrated from Asia to North America, late in the Pleistocene, during a mild period, when it was possible to walk dryshod across the Bering Straits. Such intervals occurred at the begining and end of an interglacial, when sufficient water was held up in ice sheets to lower the sea level and create a chain of islands across Beringia. During the peak of a glaciation the sea level would be still lower, but the temperatures would also have been much lower, thus making travel difficult and food hard to find.

M. columbi lived in warm grasslands in the south-eastern part of the continent, and may even have moved as far south as Mexico.

M. columbi had twisted tusks, which perhaps distinguish it from the other American mammoth M. imperator, whose long tusks curled backward in an even curve. This latter species or subspecies had a more westerly range and its remains have been found in the tar deposits of Rancho La Brea in Los Angeles.

name: Mammuthus primigenius time: Late Pleistocene locality: Europe, Asia and North

America size: 9 ft/2.7 high

M. primigenius, the wooly mammoth, is what most people think of as the typical mammoth. Relatively small for a mammoth, it was a cold-climate tundra-dweller, with a thick shaggy coat and a fatty hump.

Paleontologists are quite familiar with the animal's soft anatomy and appearance in life, since several well-preserved remains have been found buried in frozen mud in Siberia and Alaska. There are also the eye-witness reports of early people who painted and engraved the animal on cave walls in France and Spain.

The coat consisted of long black hair — not red as in most restorations. The red coloration, seen in specimens in which the hair is preserved, was due to a chemical reaction in the hair after death.

There was an undercoat of fine hair and a thick layer of fat to help the insulation. Behind the domed head was a hump of fat, evidently used as a source of nutrition when times were hardest during the winter.

Scratches on the ivory suggest that the characteristic curving tusks were used for scraping away snow and ice from the low tundra vegetation on which it fed.

M. primigenius survived until about 10,000 years ago. The warming of the climate that accompanied the end of the last glaciation may have reduced its numbers. Overhunting by early humans probably hastened its extinction.

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