Today, there are only two sloth species, but historically, there were dozens of them, including one with a bottle-nosed snout that ate ants and another that likely resembled the ancestors of modern armadillos. Most of these extinct sloths also didn’t live in trees, because they were too big. The largest sloths — members of the genus Megatherium — were about the size of Asian bull elephants and weighed roughly 3.63 tons (8,000 pounds). Ancient...
