Why mammoths? Last isolated island populations of these huge beasts disappeared about 4 thousand years ago, when the Pleistocene extinction, which destroyed the major part of the world megafauna, was long gone. So why?
According to a new study, the last mammoths disappeared after a long, slow decline for a number of reasons.

Woolly mammoths (image Mauricio Anton valley).

Woolly mammoths (Mammuthus primigenius) loved cold dry steppes of the Northern hemisphere. Their remains, in particular, often in the vicinity of Beringia - an ancient land bridge connecting East Siberia and Alaska. On them and focus group, which was led by Glen McDonald of the University of California in Los Angeles (USA).

The combination of geographical distribution of finds and radiocarbon dates helped trace the change in the number of mammoths over 45 thousand years.

20-45 thousand years ago (from first mammoth, considered by researchers to the last glacial maximum) population of the Far North were reduced, and the inner regions of Siberia - growing. Then, in the late Dryas (about 11.5 thousand years ago), woolly mammoths, on the contrary, began to focus on the North, and some populations have been isolated on Islands. This happened even before the warmer climate has replaced steppe pine forests, peatlands and thickets of dwarf birch.

"No single phenomenon cannot be responsible for the extinction", emphasizes Mr. McDonald. Climate change brought about changes in habitats of mammoths, bringing their number has decreased. Prehistoric hunters, who at the time was passing through Beringia might also have contributed. Previous studies, by the way, have shown that people could accelerate the extinction slowly prodeminca mammoths, which had already been weakened by environmental change.

Paleontologist Ross MacPhee from the American Museum of natural history notes that the number of Russian samples, taken into account by the researchers, was dated to the old methods and requires re-analysis. However, according to him, the findings fit into the overall picture, which States that the mammoths died out a long time. He stresses that previously accepted the hypothesis of a "blitzkrieg", vikasincheraa of these animals, is less wealthy. The idea of several factors seem to Mr. McPhee very attractive, but to tie them together yet.

The study is published in the journal Nature Communications.

Based on the materials of Nature News.