What defines a human as a human? Though it’s a tricky question, paleontologists and archaeologists tend to cite a couple specific characteristics in an attempt to answer. Homo sapiens, they typically say, create complex tools, make sophisticated social and symbolic meanings and communicate with one another using words and sentences — all characteristics that are tough to find in the fossil record.
Slightly more manifest in this record is a species’ ability to walk upright, which some specialists see as one of the most defining traits of Homo sapiens, as well as a host of other hominins including Homo habilis and Homo erectus. That said, despite its importance, scientists still struggle to determine when hominin bipedalism developed, and with which specific species.
According to a new analysis of fossils in Nature, a team of researchers has found that the oldest hominin species, Sahelanthropus tchadensis, walked on two feet. This supports ...
