I never went to university https://prioritypeople.co.zw/children39s-motrin-cold-ingredients-8bfb.pdf ibuprofen and tylenol with codeine together Geneticists theorize that such mutations occur at a regular rate, with X number of mutations spontaneously appearing in the genome over Y number of years. So when geneticists make their estimates of last common ancestors, they take DNA samples from a large number of people, see how different those people's DNA are from each other, and then use some outside information to help them calculate how long it should have taken for those differences to arise. "It's basically distance equals rate times time," says David Poznik, the Stanford University scientist who did much of the dating work in his the paper with Bustamante.
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