Paternal genetic contribution to offspring condition predicted by size of male secondary sexual character

Abstract

SUMMARYWhether females can obtain genetic benefits from mate choice is contentious, and the main problem faced by previous studies of natural populations is that many factors other than paternal genes contribute to offspring fitness. Here, we use comparisons between sets of naturally occurring maternal half-sibling collared flycatchers, Ficedula albicollis, to control for this problem. We show, first, that there are paternal genetic effects on nestling fledging condition, a character related to fitness in this species. Further, the magnitude of the paternal genetic contribution to this character is related to the size of a conditiondependent male secondary sexual character. Our results demonstrate that genetic benefits from mate choice can be predicted by the size of a secondary sexual character, and therefore provide direct support for indicator models of sexual selection.

Heritability and genetic correlation between the sexes in a songbird sexual ornament

“…Potti, 1993;Morales et al, 2007). Once that genetic and environmental contributions to ornament size in blackand-white European Ficedula species are beginning to be understood (Sheldon et al, 1997;Qvarnströ m, 1999;Hegyi et al, 2002;Saetre et al, 2003;Saether et al, 2007; this study), the biggest challenge is now for researchers to explain the within and between-population differences in the degree of inhibition (Williams and Carroll, 2009) of ornament displaying in females, a trait that we show is apparently subject to large environmental/nonadditive genetic variance(s). When optimal trait expression differs between the sexes, between-sex population variation in its degree might cause geographically variable antagonistic selection , wherein genetic factors spread across populations by giving a reproductive advantage to males while disadvantaging females or vice versa.…”

Fisherian flies: benefits of female choice in a lekking sandfly

“…Power analysis (Cohen 1988) shows that with our sample size and variation in survival, we had a 95% chance of detecting a correlation coe¤cient between o¡spring survival and mating success of as little as 0.26. To put this in context, the median r-value between measures of o¡spring survival and sire attractiveness reported by ¢eld studies claiming good-genes e¡ects is 0.47 (von Schantz et al 1989;Norris 1993;Petrie 1994;Hasselquist et al 1996;Sheldon et al 1997); the equivalent ¢gure from the laboratory is 0.65 (Taylor et al 1987;Reynolds & Gross 1654 (Pinder et al 1978), after Crawley (1993. c After correcting for multiple tests of the same hypothesis (Rice 1989), this value remained signi¢cant at p50.05.…”

Phenotypic and genetic variation in emergence and development time of a trimorphic damselfly

“…In addition, sex-limited expression of colour in this system makes it impossible to assign males to the different morphs. Our study, which uses an experimental approach similar to another recent study on a polymorphic insect (Ahnesjö & Forsman, 2003), was partly inspired by previous workers who have tested indicator models in sexual selection by correlating paternal colouration traits with various measures of offspring condition or performance (Sheldon et al, 1997;Sheldon et al, 2003). The advantage of using maternal values in our study is that we could include all individuals in the analysis of the laboratory data, including males, larvae, and immature …”