Maybe we're a miracle after all ...

Paleoanthropologists have long thought that humans descended from a chimpazeelike ancestor and that early human fossils belonged to a single evolving lineage. According to this view, only later did our predecessors diversify into multiple overlapping branches of humans, of which our species is the sole survivor.

Recent fossil discoveries have upended that scenario, however, providing intriguing evidence that the last common ancestor of humans and chimpanzees may not have looked particularly chimplike and that our early forebearers were not alone in Africa. The findings are forcing researchers to reconsider what traits indicate that a species belongs on the line leading to us -- and to question whether it will ever be possible to identify our last common ancestor.

--Scientific American (February 2013), p. 44; image from