Ardipithecus ramidus May Have Walked and Climbed

NEW YORK CITY, NEW YORK—Science News reports that a new study suggests Ardipithecus ramidus, which lived some 4.4 million years ago and has been nicknamed “Ardi,” was able to both walk upright like a human and climb trees like an ape. Biological anthropologists Elaine Kozma and Herman Pontzer of the City University of New York, and an international team of researchers, collected data from the measurements of an 18-million-year-old pelvis from Ekembo nyanzae, an African ape; an Ardipithecus ramidus pelvis; and the pelvises of Lucy, a 3.2-million-year-old Australopithecus afarensis individual; and a 2.5 million-year-old Australopithecus africanus. The scientists then compared the measurements to data collected from the pelvises of modern humans, chimpanzees, and monkeys. In this way, the scientists were able to evaluate the relationship between the shape and orientation of the creatures’ lower pelvises and their ability to walk and climb. “Ardi evolved a solution to an upright stance, with powerful hips for climbing that could fully extend while walking, that we don’t see in apes or humans today,” Pontzer explained. The study also suggests that Australopithecus afarensis and Australopithecus africanus would have been able to walk upright, but had lost the ape-like climbing power possessed by Ardi. An earlier study of Ardi’s lower back also suggests it was flexible enough to support upright, straight-legged walking. For more, go to “Cosmic Rays and Australopithecines.”