The Ecology of Selection in Hybrid Populations of Tribolium castaneum

Abstract

Generation 1 adults removed after 3 dtl~, counted, cluaified and discarded Generation 2 adults re111oved after 3 de.ys, counted, clauitied and discan!ed lm111atures sa~t~plllld at pr~de ter~nined intervals raised at loor densities, adults counted andcl.IISsified rrr r UUDTI C.nent:ion 1 adults tranlllferred to c•sua jar after 3 daya; e,li.g& counted and replaced in cUlture jar 200 100 ,100 100 •&&• ~ll ,_.if: pu~e 200 100 100 100 egga an large pupae ,.._,.,_ 200 egga in Barlly-We1nbllrl l)'lati.c~s

Fitness components estimated from population budgets of genotypic mixtures and hybrid populations of Tribolium

“…4). This is quite consistent with previous findings (Sokal & Sonleitner, 1968;Kence, 1973) Underlined groups not significantly different by sum of squares simultaneous tesl procedure at P < .05. below. Unexpectedly, generation 2 had a faster mean developmental rate than generation 1 despite the higher population density.…”

“…The work was carried out to follow up on part of the study reported by Sokal & Sonleitner (1968) in which the two strains were mixed at various initial gene frequencies in Hardy-Weinberg proportions and observed for up to 25 generations. Sokal & The strains used were the Chicago Black strain marked with the autosomal semi-dominant black (bb) gene located in linkage group III (Sokoloff, 1966) and UPF, the Purdue University synthetic wild type strain.…”

Ecological differences between genotypes in a natural population of Daphnia magna

“…THE occurrence of genetic variation in primary fitness components has been well established in laboratory experiments (Dobzhansky, Lewontin and Pavlovsky, 1964;Sokal and Sonleitner, 1968). Studies on wild populations have been much more restricted because determination of characters such as fecundity or developmental rate ordinarily requires continuous monitoring of individuals.…”

Genetic variation and the ability to colonise new niches in the flour beetle Tribolium castaneum (Herbst) (Coleoptera, Tenebrionidae)

“…This suggests that new genetic combinations were formed in the synthetic strain which could exploit new resources when they became available. One explanation for the higher population size of genetically heterogeneous populations compared with populations with a more limited genetic background (e.g., Sokal and Sonleitner, 1968) may be that different genotypes use different sub-niches so that competition among them is minimized. Another possibility is "genetic facilitation" among genotypes (Lewontin 1955;Sokal and Huber 1963;Bryant 1969).…”