Zigzagman
5-8-11, 6:55pm
I dvr'ed this program last week from PBS and just watched it today. I thought it was fascinating.
By analyzing DNA from people in all regions of the world, geneticist Spencer Wells has concluded that all humans alive today are descended from a single man who lived in Africa around 60,000 years ago.
Today, there is general agreement that Homo erectus, the precursor to modern humans, evolved in Africa and gradually expanded to Eurasia beginning about 1.7 million years ago. By around 100,000 years ago, several species of hominids populated the Earth, including H. sapiens in Africa, H. erectus in Southeast Asia and China, and Neandertals in Europe.
By around 30,000 years ago, the only surviving hominid species was H. sapiens.
But when did we leave Africa and where did we go? Here's where opinions diverge widely.
Wells says his evidence based on DNA in the Y-chromosome indicates that the exodus began between 60,000 and 50,000 years ago.
In his view, the early travelers followed the southern coastline of Asia, crossed about 250 kilometers [155 miles] of sea, and colonized Australia by around 50,000 years ago. The Aborigines of Australia, Wells says, are the descendants of the first wave of migration out of Africa.
The story takes it from that point and progresses around the globe from a DNA perspective. Like most National Geographic documentaries this was very well done and very enjoyable to watch.
We are all part of the same genetic family tree - sometimes we forget that.
Peace
I just found out that this is available on You-tube (http://www.youtube.com/watch?v=OV6A8oGtPc4). It is split into 13 segments but well worth watching.
By analyzing DNA from people in all regions of the world, geneticist Spencer Wells has concluded that all humans alive today are descended from a single man who lived in Africa around 60,000 years ago.
Today, there is general agreement that Homo erectus, the precursor to modern humans, evolved in Africa and gradually expanded to Eurasia beginning about 1.7 million years ago. By around 100,000 years ago, several species of hominids populated the Earth, including H. sapiens in Africa, H. erectus in Southeast Asia and China, and Neandertals in Europe.
By around 30,000 years ago, the only surviving hominid species was H. sapiens.
But when did we leave Africa and where did we go? Here's where opinions diverge widely.
Wells says his evidence based on DNA in the Y-chromosome indicates that the exodus began between 60,000 and 50,000 years ago.
In his view, the early travelers followed the southern coastline of Asia, crossed about 250 kilometers [155 miles] of sea, and colonized Australia by around 50,000 years ago. The Aborigines of Australia, Wells says, are the descendants of the first wave of migration out of Africa.
The story takes it from that point and progresses around the globe from a DNA perspective. Like most National Geographic documentaries this was very well done and very enjoyable to watch.
We are all part of the same genetic family tree - sometimes we forget that.
Peace
I just found out that this is available on You-tube (http://www.youtube.com/watch?v=OV6A8oGtPc4). It is split into 13 segments but well worth watching.