Unlike many extinct animals, mammoths have been found frozen in Siberian permafrost for centuries, giving scientists a chance to study them very closely. The permafrost yields not only the fossilized bones of these animals, but also the frozen flesh. There were several species of mammoth living in Eurasia and North America. The woolly mammoth, (Mammuthus primigenius) was actually the smallest member of this group, though as one of the last to survive this species looms as famous.
Mammoth Relatives
Mammoths belonged to the order Proboscidea just as elephants, both Asian and African do. Aside from elephants, the closest relatives to mammoths and all proboscideans are rock hyraxes, manatees and dugongs. Although these animals are markedly different from one another, inhabiting various habitats and dissimilar body forms, scientists have been united in naming them as relatives for some time. It was proposed with morphological evidence first, comparing physical features, but also more recently genetic evidence has helped link hyraxes, dugongs, and manatees to proboscideans.
Mammoth Ancestors
Sometime between 60 and 70 million years ago, pig-sized animals developed and distinguished themselves from other plant eating mammals of the time into the first recognized proboscideans. This first grouping was called the Moeritheres. These were pig-sized quadrupeds that had stubby legs, possibly a very short trunk like a modern-day tapir, and pointy tusks. They lived around 55 to 60 million years ago in Africa and were probably fond of wet habitats like marshes, wetlands, and swamps.
Around 40 million years ago a new group arose called the Palaeomastodons. These animals and their relatives form the stem of the mammoth and elephant family tree. They were larger, cow-sized, with a bit of a trunk and larger tusks. They resembled elephants and mammoths much more than the hippo-like Moeritheres.
The Family Elephantidae
The family Elephantidae appeared only 5 million years ago with Primeelephas which looked basically like today’s modern elephants. The African and Asian elephant originated in Africa with the mammoth, all closely related species. Asian elephants headed out of Africa, as did the mammoths, leaving African elephants alone on the continent.
Mammoths specifically evolved from the African mammoth, (Mammuthus africanavus). They lived in Northern Africa between 4 and 3 million years old. Their descendants migrated north all over Eurasia and were called the “southern mammoths,” Mammuthus meridionalis. It was this mammoth species that migrated first to North America in the early Pleistocene. By the middle Pleistocene this mammoth had evolved into a new North American species: the Imperial mammoth (Mammuthus imperator). The Columbian Mammoth appeared in the late Pleistocene (Mammuthus columbi or Mammuthus jeffersoni).
The Woolly Mammoth
The traditional woolly mammoth, often wrongly assumed to be the only elephantine species during the Ice Age, evolved back in Eurasia from the steppe mammoth (Mammuthus trogontherii), which lived some 200,000 years ago. Mammuthus primigenius appeared at last.
Woolly mammoths were actually the smallest of the mammoths species discussed here but survived up to 5,000 years ago. it had long, thick, reddish-brown fur, making its common name very apt. unlike modern day elephants, woolly mammoths had small ears and a humped back to stay warm during long, bitter cold streaks. Males and females had tusks, as in modern African elephants.
It crossed into North America by way of the Bering land bridge just as the “southern mammoth” had done before it. In North America their southern migration spread as far south as what is now Kansas.
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