N

and then solving in terms of the effective population size

gives an expression that can be applied to the simulation data. Table 3.4 shows the computational steps required to estimate N1 for the 10 replicate populations. In a similar fashion, Table 3.5 works through the computations necessary to estimate N ve for the 10 replicate populations using equation 3.56.

The estimates of N ve and N1e are close to each other but both are an order of magnitude lower than the expected population size of 28 or 29. What happened? The estimates are poor for a number of reasons that

Table 3.4 Data from simulated allele frequencies in Fig. 3.20 used to estimate the effective population size. Here, the ratio of heterozygosity in generations three and four is used to estimate inbreeding effective population size (N'e) according to equation 3.59. Initial allele frequencies were p = q = 0.5, so Ht=1 = 0.5. One generation of genetic drift took place, hence 1 is used in the numerator of the expression for N'e. The average N e excludes the negative values.

Table 3.4 Data from simulated allele frequencies in Fig. 3.20 used to estimate the effective population size. Here, the ratio of heterozygosity in generations three and four is used to estimate inbreeding effective population size (N'e) according to equation 3.59. Initial allele frequencies were p = q = 0.5, so Ht=1 = 0.5. One generation of genetic drift took place, hence 1 is used in the numerator of the expression for N'e. The average N e excludes the negative values.

H=3

Ht=4

In

Ht=4

0 0

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