Posted on 08/06/2010 6:41:18 PM PDT by SunkenCiv
At some point between 195,000 and 123,000 years ago, the population size of Homo sapiens plummeted, thanks to cold, dry climate conditions that left much of our ancestors' African homeland uninhabitable. Everyone alive today is descended from a group of people from a single region who survived this catastrophe...
...studies of the DNA of modern-day people indicate that, once upon a time, our ancestors did in fact undergo a dramatic population decline. Although scientists lack a precise timeline for the origin and near extinction of our species, we can surmise from the fossil record that our forebears arose throughout Africa shortly before 195,000 years ago. Back then the climate was mild and food was plentiful; life was good. But around 195,000 years ago, conditions began to deteriorate. The planet entered a long glacial stage known as Marine Isotope Stage 6 (MIS6) that lasted until roughly 123,000 years ago.
A detailed record of Africa's environmental conditions during glacial stage 6 does not exist, but based on more recent, better-known glacial stages, climatologists surmise that it was almost certainly cool and arid and that its deserts were probably significantly expanded relative to their modern extents. Much of the landmass would have been uninhabitable. While the planet was in the grip of this icy regime, the number of people plummeted perilously -- from more than 10,000 breeding individuals to just hundreds. Estimates of exactly when this bottleneck occurred and how small the population became vary among genetic studies, but all of them indicate that everyone alive today is descended from a small population that lived in one region of Africa sometime during this global cooling phase.
(Excerpt) Read more at scientificamerican.com ...
I'm doubtful. Do you have a source for this info.
SunkenCiv had nothing to do with the naming of GGG. This was done by an ex-FReeper named SabreTooth, Ernest-at-the-Beach and myself, a long time ago before SunkenCiv joined us.
(Albeit, GGG probably would have died some time back without the excellent dedication of SunkenCiv...my 'hat is off to him.')
http://en.wikipedia.org/wiki/Mitochondrial_Eve
This says 200,000. I couldve sworn it was 20,000, so I don’t know if they moved it backwards, or I remembered it wrong.
Okay, thanks.
Heh, never noticed that one, or its nuking. That big pile of drivel near the top should have been nuked as well.
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