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Why do you think lactose intolerance came about, if not as evolution's way to ensure that the available milk went to those who needed it because they were not y
by raldi 12y ago
Why do you think lactose intolerance came about, if not as evolution's way to ensure that the available milk went to those who needed it because they were not yet old enough to eat normal food?
- samatman 12y agoProducing lactase is costly, those proteins could be doing other things. What's the evolutionary selection pressure to continue digesting a food source that's only present in the infant diet? None.
- raldi 12y agoThat's circular reasoning. The only reason it was "only present in the infant diet" is because of the evolution of lactose intolerance. Without that development, children would keep drinking milk for as long as they could get away with it. But don't take my word for it; here's what Slate has to say: "With Cain weaned, Abel could claim more of his mother's attention and all of her milk. This kept a lid on sibling rivalry [...] while allowing women to bear more young." http://www.slate.com/articles/health_and_science/human_evolution/2012/10/evolution_of_lactose_tolerance_why_do_humans_keep_drinking_milk.html http://www.slate.com/articles/health_and_science/human_evolu...