I read something similar recently (though the blog post itself is from 2008): http://phenomena.nationalgeographic.com/2008/10/06/human-gut-bacteria-linked-to-ob

I read something similar recently (though the blog post itself is from 2008): http://phenomena.nationalgeographic.com/2008/10/06/human-gut-bacteria-linked-to-obesity/ http://phenomena.nationalgeographic.com/2008/10/06/human-gut... The whole gut bacteria thing is quite fascinating. It evolves depending on our diet. The intestinal flora of a fetus is boootstrapped with bacteria from his mother. Gut bacterias can get genes from ingested bacterias: http://phenomena.nationalgeographic.com/2010/04/07/gut-bacteria-in-japanese-people-borrowed-sushi-digesting-genes-from-ocean-bacteria/ http://phenomena.nationalgeographic.com/2010/04/07/gut-bacte... And this kind of symbiosis with bacterias is not limited to humans (the rumen of cows is filled with bacterias that break down normally undigestible components of grass such as cellulose.) I bet research on this symbiosis will produce lots of interesting results!