The AA population has been in the US for an average of about five generations and we do not have evidence of major immigration for the current AA generation, so gene flow resulting in HWD in our AA sample is unlikely.
The smaller N, the fewer generations lasts this similitude; say three generations for N = 10 and about six generations for N = 50.
For his information, there are about three generations of contemporary African-American and Hispanic writers who have successfully captured the rhythms of jazz in their work.
"You can maintain a Jewish identity for only about four generations after the rituals are given up," said Rabbi Buchwald, who founded the National Jewish Outreach Program, which offers crash courses like basic Judaism and Hebrew.
If genetic screening is not feasible, we suggest propagating the wild progenitor for about ten generations, using only one individual from each generation as a parent for the next, and then using the F10 generation individual to establish an inbred stock of "clonal" individuals.
Apparently the loss of penicillin production is partly reversible after a period of cultivation under carbon excess conditions, which lasted in this case for about ten generations.
An additional study of Atlantic salmon conducted as a 'common garden' experiment concluded that offspring of a locally derived hatchery population that had been completely segregated from the wild population for about five generations exhibited survival equal to offspring of the wild fish from egg to adult (McGinnity et al. 2004).
Cells were grown in biological triplicates in 1.2% (v/v) 2-butanol and harvested at OD600 ≈ 1 (corresponding to roughly 1 x 10 cells/ml), a point at which exponential growth would still continue for about two generations and nutrient limitation would not be a major problem.
Thus, about four generations of monarchs occur annually.
Even if two thirds of the original innovations are adaptive ones, and only one item in twenty becomes garbled or obsolete in each generation, their model tells us that if the average innovation hangs around for more than about seven generations, cultural learning itself becomes maladaptive.
For pedigree BLUP, G ¯ reached a plateau after about two generations of selection.
