Introduction to evolution: Difference between revisions

Revision as of 19:08, 9 December 2006

Revision as of 19:19, 9 December 2006

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The Hardy-Weinberg Theorem states that: The frequencies of alleles in a population’s gene pool will not change over time unless acted upon by forces other than both random reshuffling of alleles during sex cell formation and random combination of sex cells during fertilization.

For example: In a population of mice that inhabit a barn, there are only two variations in the gene that controls fur color. One allele codes for black and accounts for 75% of the gene pool, the other for white, which accounts for the remaining 25%. According to the Hardy-Weinberg Theorem, if only the only factors determining an allele’s potential to be passed on to the next generation are random formation of sex cells and fertilization; the frequencies will remain 75% black and 25% white. In this case, no changes in the frequencies of alleles in the mouse population, thus no microevolution, at least in regards to fur color. Such a population is said to be in Hardy-Weinberg Equilibrium

For a population to exist in Hardy-Weinberg Equilibrium the following conditions must be met.