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Extra-pair Offspring (extra-pair + offspring)
Selected AbstractsLack of evidence for improved immune response of extra-pair nestlings in collared flycatcher Ficedula albicollisJOURNAL OF AVIAN BIOLOGY, Issue 5 2008Tomasz Wilk Extra-pair paternity is common in many socially monogamous bird species. Increasing evidence suggests that extra-pair copulations are female-driven, but benefits for females mating outside social pair-bonds are still poorly understood. The most influential explanation, "good genes" hypothesis, states that females mated socially with low quality males, engage in extra-pair copulations to obtain genetic benefits for their progeny. According to this model, enhanced performance of extra-pair offspring is expected. Here, based on 4-year study of collared flycatcher Ficedula albicollis, we compared the condition of extra-pair and within-pair young. We found no difference in immune response and body size between maternal half-siblings raised in the same nests. Additionally sex ratio was not biased among extra-pair nestlings, and paternity was not associated with hatching rank. Our results failed to reveal "good genes" effects in the studied population. These effects might be hard to detect, but other hypotheses should also be studied more thoroughly in the future. [source] Does male extra-territory foray effort affect fertilization success in hooded warblers Wilsonia citrina?JOURNAL OF AVIAN BIOLOGY, Issue 6 2005Bridget J. M. Stutchbury Hooded warbler Wilsonia citrina males vary greatly in the frequency and duration of their off-territory forays in search of extra-pair copulations. We used radiotracking and microsatellite parentage analysis in high and low density populations to determine if (1) high foray rate or time off-territory reduces within-pair fertilization success, and (2) if a high foray rate onto the territory of a fertile female increases the likelihood of obtaining EPFs with that female. Males who left their territory often, or for longer periods, did not have lower within-pair fertilization success. Some males repeatedly visited a neighboring fertile female, but in only 3 of 19 cases where radiotagged males visited a fertile female did the male actually sire offspring with that female. Male foray rate onto a fertile female's territory was not a good predictor of whether or not he sired extra-pair offspring with that female. We suggest that mate choice and extra-pair behavior by females may explain why male foray behavior does not correspond closely with actual fertilization success. [source] Extra pair paternity in birds: a review of interspecific variation and adaptive functionMOLECULAR ECOLOGY, Issue 11 2002Simon C. Griffith Abstract The application of molecular genetic techniques has revolutionized our view of avian mating systems. Contrary to prior expectations, birds are only very rarely sexually monogamous, with ,extra-pair offspring' found in approximately 90% of species. Even among socially monogamous species, over 11% of offspring are, on average, the result of extra-pair paternity (EPP). Based on over 150 molecular genetic studies of EPP in birds, we review two topical areas: (i) ecological explanations for interspecific variation in the rate of EPP; and (ii) evidence bearing on the adaptive function of EPP. We highlight the remaining challenges of understanding the relative roles of genes and ecology in determining variation between taxa in the rate of extra paternity, and testing for differences between extra-pair offspring and those sired within-pair. [source] | ||||||||||