Woolly Mammoth - Extinction

Extinction

Most woolly mammoth populations disappeared during the late Pleistocene and early Holocene, alongside most of the Pleistocene megafauna, during the Quaternary extinction event. Scientists are divided over whether hunting or climate change, which led to the disappearance of its habitat, was the main factor that contributed to the extinction of the woolly mammoth, but it is likely that it was a combination of the two. Whatever the cause, large mammals are generally more vulnerable than smaller ones due to their smaller population size and low reproduction rates. Different woolly mammoth populations did not die out simultaneously across their range, but gradually went extinct over time. The last mainland population existed in the Kyttyk Peninsula of Siberia 9,650 years ago. A small population of woolly mammoths survived on St. Paul Island, Alaska, until 6,400 years ago. The last known population remained on Wrangel Island in the Arctic Ocean until 4,000 years ago.

A 2008 study estimated that changes in climate shrank suitable mammoth habitat from 7,700,000 km2 (3,000,000 sq mi) 42,000 years ago to 800,000 km2 (310,000 sq mi) 6,000 years ago. Woolly mammoths survived an even greater loss of habitat at the end of the Saale glaciation 125,000 years ago, and it is likely that humans hunted the remaining populations to extinction at the end of the last glacial period. Studies of a 11,300–11,000 year old trackway in southwestern Canada showed that M. primigenius was in decline while coexisting with humans, since far fewer tracks of juveniles were identified than would be expected in a normal herd.

A 2010 study hypothesises that the decline of the woolly mammoth could have increased temperatures by up to 0.2°C at high latitudes in the northern hemisphere. Mammoths frequently ate birch trees, creating a grassland habitat. With the disappearance of mammoths, birch forests, which absorb more sunlight than grasslands, expanded, leading to regional warming.