Abstract
An approximation method for calculating the effective generation interval in populations with overlapping generations was presented and illustrated with Drosophila melanogaster data where a sustained heterosis (or pseudo-overdominance) was observed for sex-linked genes balanced by an inversion. An equilibrium frequeney was established in replicated 2-bottle population eages which was different for males and females. The fitnesses of the genotypes were thus estimable and the expected gene frequencies with diserete generations were calculated. The effective generation interval was estimated by fitting the observed frequencies to those expected by minimizing the lack of fit chisquare. The best fit resulted if the interval was allowed to increase as the population approached a stable age distribution. The best estimate indicated that there was an average interval of 14.75 days per generation in the first 5 generations and 16.25 days thereafter. This estimate is particular to 2-bottle eages; as the number of bottles increases the expected generation interval is also expected to inerease.
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Journal Paper Number 79-5-211 of the University of Kentucky Agricultural Experiment Station, and Journal Paper Number 7942 of the Purdue University Agricultural Experiment Station.
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Muir, W.M., Bell, A.E. Estimation of effective generation interval in Drosophila population cages. Genetica 55, 33–37 (1981). https://doi.org/10.1007/BF00134001
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DOI: https://doi.org/10.1007/BF00134001