Saturday, February 9, 2008

Got Milk?

What does Natural Selection have to do with lactose intolerance? Read below to find out!

Medical News Today
9 February 2008

Got Milk?


If you're lactose intolerant, you're not alone most of the world's adults can't digest this sugar found in milk. African tribal people who took up cattle herding thousands of years ago are an interesting exception. Sarah Tishkoff of the University of Maryland discovered that natural selection for lactose tolerance was so strong that it evolved independently in three distinct rural African populations. Lactose tolerance enabled people to drink cow's milk during droughts and survive to produce more offspring who also carried the trait.

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