A photo taken in 2002 shows the jaw from the skeleton of a giant marsupial lion, thylacoleo carnifex, from a cave in the Nullarbor Plain. Caves in the Sun-scorched, treeless wilderness of southern Australia's Nullarbor plain have revealed one of the world's most remarkable collections of fossils, including species of now-extinct kangaroos that lived hundreds of thousands of years ago.(AFP/HO/File/Clay Bryce)