ANTH 203 Lecture : Part 4 Evolution and Modern Humans Chapter 14, 15
12 Apr 2012
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Document Summary
Human vary in numerous ways: language, culture, fashion, technology, architecture etc. Culture is an important source of environmental variation. It is difficult to determine the relative importance of genetic and environmental influences for particular phenotypic traits: both genetic transmission and shared environments cause parents and offspring to be similar. Genetic variation is governed by the processes of organic evolution: mutation, drift and selection. By establishing the connection between particular dna sequences and specific traits, scientists have shown that variation in some traits is genetic. We can prove that traits are controlled by genes at a single genetic locus by showing that their patterns of inheritance conform to mendel"s principles. Mutation can maintain deleterious genes in populations, but only at a low frequency. Many diseases are caused by recessive genes: natural selection steadily removes such genes but they are constantly being reintroduced by mutation.
