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101.
M. H. D. Larmuseau J. Vanoverbeke A. Van Geystelen G. Defraene N. Vanderheyden K. Matthys T. Wenseleers R. Decorte 《Proceedings. Biological sciences / The Royal Society》2013,280(1772)
Recent evidence suggests that seeking out extra-pair paternity (EPP) can be a viable alternative reproductive strategy for both males and females in many pair-bonded species, including humans. Accurate data on EPP rates in humans, however, are scant and mostly restricted to extant populations. Here, we provide the first large-scale, unbiased genetic study of historical EPP rates in a Western European human population based on combining Y-chromosomal data to infer genetic patrilineages with genealogical and surname data, which reflect known historical presumed paternity. Using two independent methods, we estimate that over the last few centuries, EPP rates in Flanders (Belgium) were only around 1–2% per generation. This figure is substantially lower than the 8–30% per generation reported in some behavioural studies on historical EPP rates, but comparable with the rates reported by other genetic studies of contemporary Western European populations. These results suggest that human EPP rates have not changed substantially during the last 400 years in Flanders and imply that legal genealogies rarely differ from the biological ones. This result has significant implications for a diverse set of fields, including human population genetics, historical demography, forensic science and human sociobiology. 相似文献
102.
Mating outside the pair-bond occurs frequently in socially monogamous birds, but the benefits that females gain from this behaviour remain debated. One hypothesis is that females engage in extra-pair copulations (EPCs) to ensure that their clutch is fertilised in case their own mate is infertile, but evidence for this idea is scarce. We report on a case of an infertile male blue tit that bred in three successive years with three different females. In the first year, all eggs were sired by an extra-pair male whereas in the second year all eggs were unfertilised and contained no sperm. In the third year, the female produced two clutches that were fertilised by an extra-pair male, but – unlike ‘normal’ clutches – sperm numbers on the perivitelline membrane decreased rapidly over the laying sequence. Our findings show that blue tit females mated to an infertile male can escape reproductive failure by engaging in EPCs and support previous suggestions that EPCs in blue tits cease after the onset of egg laying. 相似文献
103.
Mate choice in Darwin's Finches 总被引:2,自引:0,他引:2
B. R. GRANT P. R. GRANT 《Biological journal of the Linnean Society. Linnean Society of London》1987,32(3):247-270
Female Geospiza conirostris on Isla Genovesa, Galapagos, pair preferentially with males who have had previous breeding experience. They choose mates on the basis of courtship behaviour and black adult plumage. By mating with experienced black males, they gain a fitness advantage in terms of fledgling production and recruitment of young into the breeding population. Behavioural signs of past breeding experience and black plumage are reliable age- and condition-dependent traits. We suggest that females use conspicuous black plumage to identify old males at a distance, then interactions through courtship to modify initial assessments. Females paired with inferior males may increase the genetic quality of their offspring by extra-pair copulations; results of heritability analysis of morphology are consistent with this suggestion. Females change mates at a frequency of 12–27% per breeding season. They re-pair with males who are generally old, experienced, and hold territories adjacent to the deserted male. Females that re-pair gain a benefit, whereas males who are deserted within a breeding season incur a cost of more than 50% of their future potential production for that season. We conclude that females in choosing males seek reliable indicators of potential parental care, and in addition they may seek indicators of genetic quality. 相似文献
104.
Giuseppe Boncoraglio Manuela Caprioli Nicola Saino 《Proceedings. Biological sciences / The Royal Society》2009,276(1664):2117-2123
Kin selection theory predicts that, in species where progeny members compete for limiting parental care, individual offspring should be more prone to monopolize parental resources as their genetic relatedness to brood competitors decreases. Mixed parentage among broodmates may arise as a consequence, for example, of extra-pair fertilization or brood parasitism events. In this experimental study of barn swallows (Hirundo rustica), we reciprocally partially cross-fostered hatchlings between broods and compared the behaviour of pairs of related and unrelated broodmates in a competitive context, both under normal food provisioning regime and after mild food deprivation. We found that scramble competition for food mediated by visual and vocal solicitation displays (begging) is inversely related to relatedness among competitors, independent of their level of satiation. Nestlings may modulate their competitive behaviour according to vocal cues that vary with their origin and allow kin recognition. We also uncover direct fitness costs to both parents and offspring arising from mixed parentage in a brood, in terms of increased parental workload and reduced survival of the nestlings. Such previously neglected costs may select for reduced frequency of extra-pair fertilizations and brood parasitism in species with extensive parental care. 相似文献
105.
Several hypotheses have been proposed to explain why femalebirds either
copulate repeatedly with a single mate or copulatewith multiple partners even
though only a single copulationmay be sufficient to fertilize an entire
clutch. We hypothesizethat females may directly benefit from high frequencies
of copulationand multiple copulation partners if they receive a cloacal
inoculationof beneficial sexually transmitted microbes (STMs) that caneither
protect them against future encounters with pathogensand/or serve as therapy
against present infections. Experimentsin domestic animal production,
wildlife rehabilitation, andclinical medicine indicate that inoculations of
beneficial microbesderived from the indigenous microflora of hosts can lead
tonutritional benefits, resistance to colonization by pathogens,the
elimination of infection, and improved immune system functioningin
recipients. Our hypothesis predicts greater copulatory rateswhen the
probability of the transmission of beneficial microbesexceeds that of
pathogens and when the positive effects of beneficialmicrobes on host fitness
exceed the negative effects of pathogens.Patterns of copulatory behavior in
birds suggest the potentialutility of our hypothesis. We discuss our
hypothesis in thecontext of observed patterns of copulation in birds and
proposesome ways to directly test our hypothesis. Information on the
probabilitiesof transmission during copulation of beneficial and pathogenic
microbesand their relative potencies in birds are needed to directlytest the
predictions of our hypothesis. 相似文献
106.
《Current biology : CB》2023,33(8):1431-1447.e22