Traits Are Heritable

Traits Are Heritable - natural selection . The word "...

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Traits Are Heritable Those individuals that reproduce more will pass their superior genes to the next generation. Individuals that reproduce less as a result of "poorer genes" will not pass those genes to the next generation in high numbers. As a result, the population will change from one generation to the next. The frequency of individuals with better genes will increase. This process is called natural selection . Fitness We often hear natural selection described as "survival of the fittest." The word "fitness" used in a biological context means "reproductive." It does not have anything to do with physical fitness or strength. In the example above, it is the fastest rabbits that reproduce the most, not the strongest. Natural Selection Produces Evolutionary Change If the conditions discussed above are met, the genetic composition of the population will change from one generation to the next. This process is called
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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.

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