Homo Sapiens (modern) By Katherine Sullivan

Characteristics Average brain size: 1350 cc The forehead rises sharply, eyebrow ridges becoming very small or even absent, and the chin prominent. The Cro-Magnon culture appeared forty thousand years ago. 20,000 years ago, artwork, such as decorated tools, cave paintings, beads, ivory carvings, clay figures and musical instruments appeared.

Physical differences between Homo sapiens sapiens and Neanderthals Humans have more delicate skeletons. Relatively high foreheads and pointed chins. The brow ridges of Neanderthals and later archaic humans protrude more. An occipital bun on the back of the skull.

Cro-Magnons The Cro-Magnons are defined as modern humans that lived 10,000-35,000 years ago. There is no significant difference between these and living modern humans. In 1868, near a village in France, five skeletons (three adult males, one adult female, and one child) where uncovered. They are estimated to be 30,000 years old. With the skeletons, they also found stone tools, carved reindeer antlers, ivory pendants, and shells.

This Skull  Cro-Magnon 1, male, with a brain size of 1600 cc, which is about 200 cc more than the average modern humans.

Beginnings The earliest known remains of modern Homo sapiens were found in Ethiopia, and were initially believed to be just over 100,000 years old. At the time, researchers thought that this was unlikely for modern humans. They were later discovered to be 195,000 years old. Evidence indicates that modern humans were present in Europe 40,000 years ago, and maybe 46,000 years ago. They seem to have been in Asia for at least 60,000 years.

The Replacement Model An interpretation of the fossil record: The replacement model of Christopher Stringers and Peter Andrews suggests that modern humans evolved from archaic humans exclusively in Africa 200,000 years ago, and began migrating elsewhere and replacing Neanderthals and other late archaic humans only 40-60 thousand years ago. If this theory is correct, all living humans share a relatively modern African ancestry, with regional anatomical differences being developed relatively recently. Also, all descendants form the Homo erectus line would have presumably died.

Arguments for the this model Thus far, the earliest finds (up to 200,000 years old) of modern humans were in Africa. Fossils of modern humans in Southeast Asia at least 100,000 years ago and only 40-60 thousand years ago elsewhere in Europe and Asia. Rebecca Cann (University of California) compared DNA from various living peoples around the world and concluded that Africa has the greatest genetic diversity, suggesting that Africa is the homeland of all modern humans. Others have argued the great genetic diversity is only because more people have lived in Africa the past several hundred thousand years.

The Regional Continuity Model Another interpretation of the fossil record. Proposes that modern humans all evolved at the same time from local archaic humans in all regions of Europe, Asia, and Africa, known as the Old World. Supporters of this theory believe that while subspecies are to be expected, sufficient gene flow between various scattered populations prevented them from developing into separate species.

Bibliography http://anthro.palomar.edu/homo2/mod_homo_4.htm http://www.iht.com/articles/2005/02/16/news/human.php http://www.talkorigins.org/faqs/homs/cromagnon.html