ANTH 1001 Chapter : Exam 2 Notes
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Examples- sickle cell and other blood cell variants; lactase sufficiency. Lactase- enzyme that allows you to digest lactose, which is a sugar in milk. Humans can digest milk as babies but most of us lose the ability after weaning. Adults in some populations are lactose tolerant. Populations with long histories of dairying are typically lactose tolerant. Mutation for ability to digest milk as adults would have provided a natural selective advantage. Our species is polytypic: phenotypically different populations in a species, result of diversity of environments that we inhabit. Our populations diversify phenotypically and genetically because of natural selection, but our populations remain within single species because of gene flow. Race- not a biologically useful grouping of humans. Adaptation- evolutionary perspective, result of natural selection. Human variation perspective- any beneficial modification that relieves environmental stress and enhances survival of individuals. Types of adaptations: behavior, short-term (reversible) acclimatization, developmental (irreversible) acclimatization, genetic (result of natural selection)
