Why Did Alaska's Last Woolly Mammoths Go Extinct?

Global warming might seem like a recent phenomenon, but the truth is, climate change has been a threat to a variety of species for thousands of years. Even during an ice age, a warming planet can be devastating, as evidenced by the demise of one of the last known groups of woolly mammoths, approximately 5,600 years ago. The mammoths had been living on St. Paul Island off the coast of what is now Alaska, surviving on what they could find in such a remote location, which included water from lakes. But scientists now believe that the water evaporated during a long hot spell, and the mammoths didn't make it. In a sense, the mammoths on St. Paul Island had been lucky. Most of their kind had died 5,000 years earlier, probably due to human hunters and other causes, but the isolated group on the Bering Sea island were more protected.

According to one of the researchers, it seems likely that as the lakes shrunk, the mammoths -- as well as other creatures on the island -- began congregating en masse around whatever watering holes they could find, which led to the destruction of the surrounding vegetation. In effect, they cut off their food supply as they desperately clung to the water.

The very last known group of mammoths, on Wrangel Island in the Arctic Ocean, died out just 4,000 years ago.

A woolly world:

• Paleontologists can determine the age of a woolly mammoth and the season when it died by examining the number of rings in its tusks and their color.
• DNA research has confirmed that the Asian elephant is the closest living relative of the woolly mammoth.
• The Rouffignac cave in France is known as "The Cave of the Hundred Mammoths" because of its huge collection of paintings and carvings of woolly mammoths.