Cuzin_Dave
Active member
To expand on the basic concept of Ne one must consider how Ne effects the F statistic (Coefficient of Inbreeding).
So let's assume an NE of say 4. The decline in heterozygosity or rate of inbreeding at from the first generation would be: F1 = (1) / (2 * Ne) or 1 / (2 * 4) = .125.
With each subsequent generation the decline in heterozygosity is cumulative. Take generation F6
F6 = 1 - (1 - F1) ^ 6 = 1 - (1 - .125) ^ 6 = .551
By the 6th generation 55% of the genetic diversity will have been lost in the line. By the 12th generation 1 - (.87.5) ^ 12 = 80 % of the genetic diversity will have been eliminated.
The larger the Ne the lower the rate is the actual loss of diversity through inbreeding.
So let's assume an NE of say 4. The decline in heterozygosity or rate of inbreeding at from the first generation would be: F1 = (1) / (2 * Ne) or 1 / (2 * 4) = .125.
With each subsequent generation the decline in heterozygosity is cumulative. Take generation F6
F6 = 1 - (1 - F1) ^ 6 = 1 - (1 - .125) ^ 6 = .551
By the 6th generation 55% of the genetic diversity will have been lost in the line. By the 12th generation 1 - (.87.5) ^ 12 = 80 % of the genetic diversity will have been eliminated.
The larger the Ne the lower the rate is the actual loss of diversity through inbreeding.