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Social interactions can give rise to indirect genetic effects (IGEs), which occur when genes expressed in one individual affect the phenotype of another individual. The evolutionary dynamics of traits can be altered when there are IGEs. Sex often involves indirect effects arising from first‐order (current) or second‐order (prior) social interactions, yet IGEs are infrequently quantified for reproductive behaviors. Here, we use experimental populations of burying beetles that have experienced bidirectional selection on mating rate to test for social plasticity and IGEs associated with focal males mating with a female either without (first‐order effect) or with (second‐order effect) prior exposure to a competitor, and resource defense behavior (first‐order effect). Additive IGEs were detected for mating rate arising from (first‐order) interactions with females. For resource defense behavior, a standard variance partitioning analysis provided no evidence of additive genetic variance—either direct or indirect. However, behavior was predicted by focal size relative to that of the competitor, and size is also heritable. Assuming that behavior is causally dependent on relative size, this implies that both DGEs and IGEs do occur (and may potentially interact). The relative contribution of IGEs may differ among social behaviors related to mating which has consequences for the evolutionary trajectories of multivariate traits.

The trait-specific coefficients for the composite selection gradients. Each gradient is standardized to a length of 1

Model comparisons using Deviance Information Criterion (DIC). This method is suggested for Hadfield 2010 to determine the significant estimates from MCMC procedure

International audience; Organisms with coexisting sexual and asexual populations are ideal models for studying the consequences of either reproductive mode on the quantitative genetic architecture of life-history traits. In the aphid Rhopalosiphum padi, lineages differing in their sex investment coexist but all share a common parthenogenetic phase. Here, we studied multiple genotypes of R. padi specialized either for sexual and asexual reproduction and compared their genetic variation in fitness during the parthenogenetic phase. Specifically, we estimated maintenance costs as standard metabolic rate (SMR), together with fitness (measured as the intrinsic rate of increase and the net reproductive rate). We found that genetic variation (in terms of broad-sense heritability) in fitness was higher in asexual genotypes compared with sexual genotypes. Also, we found that asexual genotypes exhibited several positive genetic correlations indicating that body mass, whole-animal SMR, and apterous individuals production are contributing to fitness. Hence, it appears that in asexual genotypes, energy is fully allocated to maximize the production of parthenogenetic individuals, the simplest possible form of aphid repertoire of life-histories strategies.

In ecological communities, pollution driven perturbations exert immediate effects on sensitive individuals, but these effects may be transmitted among interacting organisms and spread over the community through several paths. This makes the assessment and prediction of ecological consequences of pollution difficult. The propagation of perturbation effects among organisms can be horizontal among organisms that coexist in space and time, and vertical among organism that belong to different generations. The latter process is poorly understood, in particular in planktonic organisms facing metal pollution. In this study we evaluate the vertical transfer of effects driven by sublethal copper stress on the heartbeat rate, somatic growth and fertility of Daphnia pulex. In order to evaluate this, we performed a factorial experiment in which parental and filial generations were exposed to both copper-enriched and control media. We found that parental exposure to copper exerted a significant effect on the heartbeat rate, somatic growth and fertility of offspring, revealing a transgenerational effect in D. pulex. This response may be explained by a higher resource investment on repair/detoxification processes in the parental generation, allocating fewer resources to offspring quality. Our results suggest that responsiveness of organisms to stress is dependent on parental history. En las comunidades ecológicas, las perturbaciones producidas por los contaminantes ejercen efectos inmediatos en los individuos sensibles, pero estos efectos podrían ser transmitidos entre los organismos interactuantes y extenderse sobre la comunidad a través de múltiples vías. Esto hace difícil la evaluación y predicción de las consecuencias ecológicas de la contaminación. La propagación de los efectos de una perturbación entre los organismos puede ser horizontal, entre organismos que coexisten espacial y temporalmente, y vertical, entre organismos que pertenecen a generaciones diferentes. Este último proceso ha sido escasamente entendido, en particular en organismos planctónicos enfrentados a contaminación por metales. En este estudio evaluamos la transferencia vertical de los efectos producidos por un estrés subletal de cobre sobre la tasa de latidos cardiacos, el crecimiento corporal y la fertilidad de Daphnia pulex. Para evaluar esto, se realizó un experimento factorial en el cual las generaciones parental y filial fueron expuestas tanto a medios enriquecidos con cobre como a medios control. Encontramos que la exposición de las madres al cobre ejerció un efecto significativo en la tasa de latidos cardiacos, el crecimiento corporal y la fertilidad de la descendencia, revelando un efecto transgeneracional en D. pulex. Esta respuesta puede explicarse por una mayor inversión de recursos en los procesos de reparación/ desintoxicación en la generación parental, asignando menos recursos a la calidad de su descendencia. Nuestros resultados sugieren que la reactividad de los organismos al estrés depende de la historia parental.