Consider a simplistic life cycle where the genotypes (a single locus way of referring to adults) produce gametes . These gametes mate to form new genotypes (=adults). See 5.1, pg. 93 and 5.3, pg. 99. The relationship between allele frequencies (sometimes called "gene" frequencies) and genotype frequencies is determined by the Hardy Weinberg Theorem which defines the probabilities by which gametes will join to produce genotypes. Consider a coin toss: probability of a head = 0.5; of a tail = 0.5; prob. of two heads = 0.5x0.5 = 0.25; prob. of one head and one tail = 0.5x0.5 = 0.25, etc. Each coin is analogous to the type of allele you can get from one of your diploid parents; the tossing of two coins is analogous to the mating of two individuals to produce four possible genotypes (but heads,tails is the same as tails,heads). Now consider a roll of the dice. The probability of each face is 1/6, and is actually analogous to cases where more than two different alleles exist in the population at a
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