Ardi stands tall: Earliest human ancestor revealed

Ardipithecus ramidus, AKA Ardi, as she may have looked 4.4m years ago Photograph: J.H. Matternes/Science

Cradle of humanity: The area where Ardi was found is rich in hominin fossil sites Photograph: AAAS/Science

Reconstructed frontal view of the skeleton. Researchers were struck by how different our common ape ancestor must have looked from modern apes Photograph: J.H. Matternes/Science

Ardi stood only four feet (1.2m) tall and weighed a little under eight stone (50kg), making her similar in size and weight to a modern chimpanzee. Her brain was also the size of a chimp's Photograph: J.H. Matternes/Science

Original and reconstructed pelvis. Ardi would have spent much of her time in the trees, but her pelvis was adapted to walking upright Photograph: AAAS/Science

Digitally rendered composite hand. Ardi had very long arms and fingers ... Photograph: AAAS/Science

... and opposable toes that would have helped her grasp branches while swinging through the forest Photograph: AAAS/Science

Digital representations of Ardi's cranium and lower jaw bone Photograph: AAAS/Science

Eleven papers from an international team are published in a special issue of the journal Science tomorrow. They describe the anatomy of the newly discovered species and its habitat and discuss the implications for human evolution. One of the take-home messages is that, like humans, living great apes have evolved considerably since we parted company with them more than 6m years ago Photograph: T. White/Science