Climate, hunting, or both

Why they died out

The cause of extinction of the woolly mammoth, Mammuthus primigenius, is still debated, a 1993 Nature letter by Vartanyan, Garutt and Sher says. A major environmental change at the Pleistocene-Holocene boundary, hunting by early man, or both together are among the main explanations that have been suggested. Nature, 1993 Scientists have been debating mammoth extinction, Lister says, with two main suspects. There is an ongoing argument among researchers as to the relative contribution of climate change and vegetation change on one hand, and human hunting on the other. Natural History Museum

The species is named for the appearance of its long thick coat of fur. Thriving during the Pleistocene ice ages, woolly mammoths died out after much of their habitat was lost as Earth’s climate warmed in the aftermath of the last ice age. Britannica Woolly mammoths were largely extinct by about 10,000 years ago, due to the pressures of a warming climate (which reduced the habitat of these cold-adapted mammals) combined with hunting by humans. Britannica

Towards the end of the Pleistocene, as Earth crept out of the last ice age, the mammoths’ open habitat started shrinking and being replaced by forest and tundra. In line with that change, the fossil record shows mammoth populations shrinking and contracting. Natural History Museum Some people would argue that that happened cyclically, Lister notes, because there were many ice age climate cycles. Woolly mammoths were squeezed into smaller favourable areas, known as refugia, in warm periods, then bounced back as the climate cooled. So why, he asks, did they only go extinct the last time around? Natural History Museum

Mammoths were important to our ancestors for food, as well as for their bones, ivory and skins. They feature in cave art, such as the 158 mammoths depicted on the walls of Rouffignac Cave in south-west France, by people 13,000 years ago. Natural History Museum We have evidence they were occasionally hunted, Lister says: there are a few mammoth fossils with broken ends of spear points in them. But that does not mean they were hunted to extinction. Natural History Museum Mammoths figured significantly in the art of primitive humans; cave dwellers in Europe realistically depicted herds of these animals. Britannica Remains of arctic plants have been found in the digestive tracts of frozen mammoth carcasses. It is clear that the mammoth was hunted by early North American hunters. Britannica

Lister thinks it may be a combination of the two. He thinks the data better fits the climate model as the main driver, but we can’t rule out that humans contributed. Natural History Museum

We last see Columbian mammoths in the fossil record about 12,000 years ago, indicating they may have gone extinct alongside lots of other large Pleistocene mammals. Natural History Museum Woolly mammoths died out on the mainland a little later, around 10,500 years ago. But populations survived on the islands left behind after the Bering land bridge was swallowed by the sea. Natural History Museum

Researchers have mapped the reduction in genetic diversity that led up to the mammoth’s extinction, which may have contributed to its ultimate demise. They have also shown how one genetic group, originating in North America, spread over a period of 40,000 years of the last ice age to replace populations in Siberia and ultimately Europe. Natural History Museum

The last island populations, and the open question of what ended the Wrangel herd, have their own page: the last mammoths.