It shounds as though the San may have been isolated genetically by the sharp worldwide population reducation caused by Toba about 74,000 years ago. As for the Australia trip, didn’t the ocean get as much as 400 feet shallower at some point in there not the 150 feet the article mentioned.
Another item. With the discovery of the Kow Marsh hominids in Australia, which although only 12,000 years old have the appearance of the pre Neanderthal Heidelburgensis, is it possible for us to learn something from their DNA?
In less than ten years, we've discovered two new human lines that were alive less the 15,000 years ago. The 'Hobbits' and the Denisovans.
New Type Of Ancient Human Found—Descendants Live Today?
This hasn't gone away either. Maybe Toba killed all the Calico people, eh?