Lucy's Older Brother

Remember “Lucy”, the first nearly complete skeleton of Australopithecus afarensis, an extinct species of early human ancestor? Well, now partial remains of her older “big brother” have been found, though technically he’s not her brother because he lived nearly half a million years earlier. But at 5 – 5 ½ feet tall he is big by early human ancestor standards. Kadanuumuu, or “big man”, as he was nicknamed, had a rib cage and shoulder blade (scapula) more like a modern human than a chimpanzee. In addition, his legs were long compared to his arms, another feature that is more humanlike than apelike.

This second Australopithecus afarensis partial skeleton strengthens the hypothesis that although early human ancestors were not entirely humanlike, they also did not resemble modern apes or chimpanzees.

Details were published online on June 21 in the Proceedings of the National Academy of Science, ahead of the print version.