A statement released by Washington University in St. Louis in St. Louis, scientists analyzed residues on pottery recovered from prehistoric sites in Kenya and Tanzania, and detected traces of cooked milk, meat, and plants. Grillo said the ability for adults to digest milk, known as lactase persistence, had been thought to have evolved in East Africa about 5,000 years ago, based upon previous genetic studies and the bones of cattle, sheep, and goats found at archaeological sites.
Most people don’t think about the fact that we are not really designed to drink milk as adults — most mammals can’t. People who had mutations that allowed them to digest fresh milk survived better in Africa.
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