The large, Ice Age big-game fauna in North America, now extinct. These Late Pleistocene food sources included mammoths, mastodon; giant bison, sloths, camels, and diprotodons. The term also covers extinct larger species of quite small animals, such as giant beavers. The late Pleistocene extinction of megafauna did not occur synchronously nor was it of equal magnitude throughout the world. Considerable doubt exists regarding the timing of the megafaunal extinction on various landmasses. Evidence suggests that the earliest mass megafaunal extinctions occurred in Australia and New Guinea about 30,000 or more years ago. Eighty-six percent of the Australian vertebrate genera whose members weighed more than 40 kilograms became extinct. Much smaller extinction events occurred in Africa, Asia, and Europe earlier in the Pleistocene, removing very large species such as rhinoceroses, elephants, and the largest artiodactyls. Other mass megafaunal extinction events occurred on the Eurasian tundra about 12,000 years ago (affecting mammoths, Irish elk, and woolly rhinoceroses); in North and South America they occurred about 11,000 years ago (affecting a wide variety of species, including elephants, giant sloths, lions, and bears). These extinctions have removed 29 percent of the vertebrate genera weighing more than 40 kilograms from Europe and 73 percent of such genera from North America. Until 1,000 to 2,000 years ago the megafauna of large, long-isolated landmasses such as New Zealand and Madagascar survived. Gigantic birds such as the elephant birds of Madagascar and the moas of New Zealand disappeared in the past few thousand years.