also argue that megafauna extinctions in South America have yet to be properly studied, but are coincident with both human immigration and climate change (7). By around 15,000 years ago, the average mass of North America’s mammals had fallen from 216 pounds to just 17. “The fact that we don’t have them here could simply be that we’ve overlooked them,” says Greg McDonald, a Bureau of Land Management paleontologist who studies extinct South American sloths. Megafauna can be found on every continent and in every country. Barnosky et al. Turns out, they're far more ancient than they look, estimated to be at least 8,000 to 10,000 years old, and no known geologic process can explain them. Though North America was also once home to giant ground sloths and giant armadillos, you won’t find paleoburrows here. “Whether it be 50,000 years ago in Australia or 13,000 years ago in South America or 1000 years ago in New Zealand: it’s a perfect match.” But the real culprit, he says, is climate change. Nov. 26, 2019 — For the first time, the research suggests a combination of climate change and the impact of people sealed the fate of megafauna, at least in south-eastern Australia. The five: extinct megafauna ... Remains of mammoths have been found on all continents except Australia and South America. Researchers have found several colossal burrows in South America that are so huge and neatly constructed, you'd be forgiven for thinking humans dug them as a passageway through the forest. Three orders disappeared (Notoungulata, Proboscidea, Litopterna), as did all large xenarthrans, but how this fits into global extinction is uncertain, mainly due … A South American Thing. During the Miocene epoch, South America was cut off from the rest of the world's continents, resulting in the evolution of a bizarre array of mammalian megafauna. The debate however is far from closed.
The megafauna extinction in South America was one of the most profound events, with the loss of 50 genera (~ 83%).
The unmaking of the megafauna is a tragedy in itself, but it …