Sure it does if you add the component missing from this article, the end of the Ice Age.
The last big 'burp' of ice melt occurred rather suddenly about 8,000 years ago. Sundaland (around Indonesia), an area the size of present day India, goes underwater and everyone there has to find somewhere else to live.
Dr Stephen Oppenheimer covers this very well in his book East Of Eden as does Dr Robert Schoch in his book Voyages Of The Pyramid Builders. They both have excellent ideas that the first Sumerians came from Sundaland.
Everywhere in that peroid was flooding and people were migrating everywhere.
So the grounds closest to the stem percolated last?