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So... okay, the picture is fuzzy, and Asia is much more important as thought. What I don't understand is, the article also says the genetical picture still poi

So... okay, the picture is fuzzy, and Asia is much more important as thought. What I don't understand is, the article also says the genetical picture still points to the established ("old") theories centering on Africa? As someone only reading about the subject on the side whenever something interesting comes up I'm slightly confused by this aspect of the article. I'm not confused about there not being a linear but a convoluted story - I never thought there was (except when I was fresh out of an East German school quite some time ago and everything being a linear progress story eventually leading to communism was quite clear :) ).

summarite 10y ago
The fixed factor is that 97℅ of our DNA matches with that of fossils in Africa. So our ancestors must have come from there, but that doesn't mean there were a few intermediate stops. Also always worth remembering that the classification as eg sapiens, heidelbergensis or erectus is not one checklist that always ticks the same boxes. In each of these groups defined by us on the basis of some common features but there is much variation. And of course there are regional or temporal differences within eg sapiens. Then you have parallel evolutions, interbreeding, fakes, unclear dating, and you never know if a particular specimen that you find really has 'typical ' features and genes for that time and space, eg it could have been that one lady/guy that happened to have wandered far from where the rest of its group remained, or could have been somewhat different. Eg imagine the only specimen that remains from our era is an inbred Egyptian pharaoh or someone with down syndrome. Those are bad examples as you could probably figure such things somewhat from the DNA, but it's not so clear for every condition, eg if epigenetics* had some bigger effect. * = A layer on your genes that De/activates or strengthens/weakens their effects and that we barely understand. The famous example is that data on Danish military recruits, which were measured upon entry into service, showed that if a man suffers starvation/malnutrition in his childhood his sons (!) will on average be less tall than others of their generation. One generation is not enough for genetic selection, so it must be a change in epigenetics.
- summarite 10y ago
  Forgot to add this second main piece of evidence that modern humans are 'out of Africa': modern African populations have more genetic diversity. When populations migrate it's not a representative sample of all genes, but rather just limited groups, so you can find most diversity at/near the place where it evolved.
- ww520 10y ago
  > The fixed factor is that 97℅ of our DNA matches with that of fossils in Africa. Chimpanzee and human DNA are 96 to 99% identical. Does the 97% DNA match between human and the African fossil have any significance at all?
  - mhuffman 10y ago
    I believe that this is being brushed over. Cats have 90% DNA matches with modern humans as well as the overlap with chimps you mentioned. It is clear that just a couple of percent different is a HUGE difference in animals (I am including humans as animals). So, while it is clear that there is some relationship, the percentage of DNA matches does not seem like strong evidence of "this follows from that" and seems more like "this and that share common previous DNA". And of course there is a political and social-responsibility component to this, even though people pretend like scientist are immune to politics or social trends.

summarite 10y ago

The fixed factor is that 97℅ of our DNA matches with that of fossils in Africa. So our ancestors must have come from there, but that doesn't mean there were a few intermediate stops. Also always worth remembering that the classification as eg sapiens, heidelbergensis or erectus is not one checklist that always ticks the same boxes. In each of these groups defined by us on the basis of some common features but there is much variation. And of course there are regional or temporal differences within eg sapiens. Then you have parallel evolutions, interbreeding, fakes, unclear dating, and you never know if a particular specimen that you find really has 'typical ' features and genes for that time and space, eg it could have been that one lady/guy that happened to have wandered far from where the rest of its group remained, or could have been somewhat different. Eg imagine the only specimen that remains from our era is an inbred Egyptian pharaoh or someone with down syndrome. Those are bad examples as you could probably figure such things somewhat from the DNA, but it's not so clear for every condition, eg if epigenetics* had some bigger effect. * = A layer on your genes that De/activates or strengthens/weakens their effects and that we barely understand. The famous example is that data on Danish military recruits, which were measured upon entry into service, showed that if a man suffers starvation/malnutrition in his childhood his sons (!) will on average be less tall than others of their generation. One generation is not enough for genetic selection, so it must be a change in epigenetics.

summarite 10y ago
Forgot to add this second main piece of evidence that modern humans are 'out of Africa': modern African populations have more genetic diversity. When populations migrate it's not a representative sample of all genes, but rather just limited groups, so you can find most diversity at/near the place where it evolved.
ww520 10y ago
> The fixed factor is that 97℅ of our DNA matches with that of fossils in Africa. Chimpanzee and human DNA are 96 to 99% identical. Does the 97% DNA match between human and the African fossil have any significance at all?
- mhuffman 10y ago
  I believe that this is being brushed over. Cats have 90% DNA matches with modern humans as well as the overlap with chimps you mentioned. It is clear that just a couple of percent different is a HUGE difference in animals (I am including humans as animals). So, while it is clear that there is some relationship, the percentage of DNA matches does not seem like strong evidence of "this follows from that" and seems more like "this and that share common previous DNA". And of course there is a political and social-responsibility component to this, even though people pretend like scientist are immune to politics or social trends.