We human beings belong to a very exclusive group of animals. There are only four types of "great apes" in existence today, those being humans, chimpanzees, orangutans, and gorillas. As the name "great ...

Some extinct mammals from Australia's Mammoth Cave included (from left) a giant long-nosed echidna, a short-faced kangaroo, a wombat-like marsupial and a Tasmanian thylacine. - Peter Schouten Recent ...