Originally posted by shahenshah
Two interesting links are given below
http://www.newscientist.com/article/dn20965-spies-could-hide-messages-in-genemodified-microbes.html

Only in the movies, would spies actually need such high tech to hide their messages. But then again, the spy industry has a record of wasting funds.

Originally posted by shahenshah
http://www.scientificamerican.com/article.cfm?id=genetics-supports-cultural-interaction-was-more-east-west-than-north-south

An interesting hypothesis, but they seem to be claiming to have proved it - with 2 samples. I am not impressed.

Originally posted by twhitehead
An interesting hypothesis, but they seem to be claiming to have proved it - with 2 samples. I am not impressed.

They haven't proved it, exactly, and it's not their hypopthesis, either. It's rather old. I recall an article by (IIRC) Asimov arguing that the native Americans were particularly susceptible to Eurasian diseases, while the opposite did not apply, for a very similar reason. After all, diseases often need vectors, which are usually limited by climate. Thus, people all over Eurasia could share, and develop a resistance to, one another's diseases, which therefore evolved to be more virulent. By contrast, diseases in America were limited to a smaller group of humans, and stayed relatively mild.
It's a pretty obvious hypothesis, if you look at a map. But "pretty obvious when you look at a map" proves nothing, of course. You need evidence other than reasoning. And that is what these people have provided - genetic evidence that backs up this existing theory. It doesn't prove anything, and in fact the article never uses that word, but it does support the theory. More evidence may be desired, but this is support for, not against it.
678 markers investigated in 68 populations is rather more than "2 samples", by the way.

Richard

Originally posted by Shallow Blue
678 markers investigated in 68 populations is rather more than "2 samples", by the way.

The two samples are the two continents. They have shown almost without a doubt that there was more interbreeding of people east-west in Eurasia than north-south in the Americas.
But they haven't shown any actual connection to 'east-west' / 'north-south'. There are hundreds of other possible explanations.
Did they do similar studies for Africa / Australia / the pacific? Why not?