SCIENCE -- October 18, 2013 at 4:48 PM ET
'Unimaginable' discovery could rewrite the history of human ancestry
It's time to prune some branches off the human family tree. In a discovery that reveals how much we have to learn about the evolution of our own species, archaeologists in the former Soviet Republic of Georgia uncovered a huge cache of pre-human bones and skulls. After eight years of analysis, the research team says the skulls have yielded their secret: human ancestry followed a relatively linear route. It turns out there were far fewer dead ends on the path through our evolution than previously thought.
PBS NewsHour Reporter/Producer David Coles interviewed Dr. Donald Johanson, co-discoverer of one of the oldest-known human ancestors known as "Lucy." Dr. Johanson will speak with Jeffrey Brown on tonight's PBS NewsHour. Dr. Johanson explained how important the Georgia skulls are to the fossil record of human evolution:
Normally we are pleased when find a chunk of bone or a handful of teeth, but this discovery far surpasses that. This is cache of bones, including nearly complete skulls, one of them nearly intact, with an antiquity of 1.8 million years. It is unimaginable that someone would make such a discovery.
One thing that is quite surprising about these fossils is their similarity with an upper jaw we found in Ethiopia dated to 2.4 million years. So it really looks like our genus arose in Africa and that Africa is really the crucible of human evolution.
But it does indicate that our ancestors had an inquisitiveness and spirit of curiosity to leave Africa and begin to populate the rest of the world.