Sloths are slow, really slow, and rather sad (but cute) creatures. They may seem like weaklings today, but their ancestors used to walk the Americas as powerhouse herbivores.
Megatherium was a genus of elephant-sized ground sloths endemic to Central America and South America that lived from the Pliocene through Pleistocene eras, existing approximately 5.3 million years.
Megatherium was one of the largest land mammals known, weighing up to eight tons, about as much as an African bull elephant. Its huge size and formidable claws make the sloths of today seem like sloth babies. Who knows how many reckless saber-tooth tigers met their end by tangling with one of these giants.