Full Text:
Elephant-dwarfing wooly mammoths, elephant-sized ground sloths and various saber-toothed cats highlighted the array of massive mammals roaming Earth between 2.6 million and 12,000 years ago. Prior research suggested that such large mammals began disappearing faster than their smaller counterparts -- a phenomenon known as size-biased extinction -- in Australia around 35,000 years ago.
With the help of emerging data from older fossil and geologic records, the new study estimated that this size-biased extinction started at least 125,000 years ago in Africa. By that point, the average African mammal was already 50 percent smaller than those on other continents, the study reported, despite the fact that larger landmasses can typically support larger mammals.Image credit: Troy Fedderson/University of Nebraska-Lincoln
