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Scientists discovered the foot bones of a 3.4-million-year-old pre-human species in 2009 in a part of Ethiopia known as Burtele. The bones belonged to a still unknown hominin, the researchers reported in March 2012 in the journal Nature. Particularly the big toe, which looks more similar to a gorilla's than a modern human's, is providing information about how humanity began to walk upright. The species also seems to have lived alongside Australopithecus afarensis, the first incontrovertible evidence for the presence of at least two pre-human species living at the same time and place around 3.4 million years ago.