My latest issue of Scientific American came in the other day. One of the articles ("When the Sea Saved Humanity") deals with how close H. Sapiens almost went extinct. This article was very interesting as it discussed climate change & the struggle to survive the changes. Note that from a certain point on in our very early period of existence for a very long time Africa went from lush landscape to desert & back proved challenging.
There is also an article "Our Neanderthal Brethren" that discusses genome sequencing & what is coming out from that. The author's point is that H. Neanderthalgensis & H. Sapien both share the same parent &, therefore, are brothers. Reviewing NOVA's 3-part series, "How We Became Human", I found the common ancestor to be H. Heidelburgensis.
The NOVA series recapped as well as made some points clear (for me). The air dates were in late 2009. This series + related information can be found on http://www.pbs.org/.
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