Human origins story given twist by fossil study
8 September 2011 Last updated at 20:01 BST
Scientists in South Africa say two skeletons could completely change our understanding of how and where humans evolved.
Humans are thought to have descended from a creature called Homo erectus, which lived more than a million years ago, and it in turn was descended from more primitive species.
But the two 1.9-million-year-old fossils, from a species known as Australopithecus sediba, suggest creatures with anatomy and capabilities more advanced than other species from the same time, making them more likely ancestors for H. erectus.
Pallab Ghosh reports.