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Unformatted text preview: natural selection . The word " evolution " refers to a change in the genetic composition of a population. Natural selection produces evolutionary change because it changes the genetic composition of populations. A variety of other mechanisms can also produce evolutionary change. For example, suppose that 65% of the eye-color genes in a population were for individuals with blue eyes and 35% of the genes were for brown eyes. If most of the immigrants entering the population carried the blue gene, the overall composition might change from 65% blue to 70% blue. Evolution occurs in populations, not in individuals. Although mechanisms exist for individual bacteria to change their genetic composition, multicellular organisms do not change their genetic characteristics and therefore cannot evolve. Natural selection does not act on an individual to make it better adapted to its environment....
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This note was uploaded on 12/15/2011 for the course BIO BSC1010 taught by Professor Gwenhauner during the Fall '10 term at Broward College.
- Fall '10