According to CNN, the Sterkfontein Caves have been the site where hundreds of Australopithecus fossils have been recovered since the site was discovered in 1936. Since then, major fossil discoveries including an almost completely intact female skull known as Mrs. Ples, and an almost complete skeleton known as Little Foot were both found there (via BBC News). However, there has been disagreement in the anthropological community about the true age of these fossils.
“Sterkfontein has more Australopithecus fossils than anywhere else in the world,” Darryl Granger, professor of Earth, atmospheric and planetary sciences in Purdue University’s College of Science, said. “But it’s hard to get a good date on them. People have looked at the animal fossils found near them and compared the ages of cave features like flowstones and gotten a range of different dates. What our data does is resolve these controversies. It shows that these fossils are old — much older than we originally thought.”