Kin-dependent dispersal influences relatedness and genetic structuring in a lek system

Abstract

Kin selection and dispersal play a critical role in the evolution of cooperative breeding systems. Limited dispersal increases relatedness in spatially structured populations (population viscosity), with the result that neighbours tend to be genealogical relatives. Yet the increase in neighbours' fitness-related performance through altruistic interaction may also result in habitat saturation and thus exacerbate local competition between kin. Our goal was to detect the footprint of kin selection and competition by examining the spatial structure of relatedness and by comparing non-effective and effective dispersal in a population of a lekking bird, Tetrao urogallus. For this purpose, we analysed capture-recapture and genetic data collected over a 6-year period on a spatially structured population of T. urogallus in France. Our findings revealed a strong spatial structure of relatedness in males. They also indicated that the population viscosity could allow male cooperation through two non-exclusive mechanisms. First, at their first lek attendance, males aggregate in a lek composed of relatives. Second, the distance corresponding to non-effective dispersal dramatically outweighed effective dispersal distance, which suggests that dispersers incur high post-settlement costs. These two mechanisms result in strong population genetic structuring in males. In females, our findings revealed a lower level of spatial structure of relatedness and genetic structure in respect to males. Additionally, non-effective dispersal and effective dispersal distances in females were highly similar, which suggests limited post-settlement costs. These results indicate that kin-dependent dispersal decisions and costs have a genetic footprint in wild populations and are factors that may be involved in the evolution of cooperative courtship.

Context‐dependent dispersal determines relatedness and genetic structure in a patchy amphibian population

“…The model includes four main parameters which are estimated from the data: ( r ) the proportion of individuals with a nondispersing phenotype, and (1 − r ) the proportion of individuals with a dispersing phenotype; ( Φ ) the probability of apparent survival; ( α ) the probability that an individual with a dispersing phenotype remains in the same pond between two sampling sessions (intra‐annual: from April/May to June/July; inter‐annual: from June/July to April/May), and (1 − α ) the probability that it moves to another pond; and ( p ) recapture probability. For one of the heterogeneity classes, the probability that individuals remained at the same pond is fixed at α = 1, which allows for identification of individuals with a nondispersing phenotype (Cayuela, Boualit, et al, 2019; Denoël et al, 2018). The model was implemented in the program e‐surge (Choquet et al, 2009).…”

Path‐finding algorithm as a dispersal assessment method for invasive species with human‐vectored long‐distance dispersal event

“…In this respect, the distance measuring method becomes the key factor that determines the accuracy of the identified dispersal pattern. To date, most of the research have used linear distance from dispersal source to destination to estimate dispersal distances (Hereafter referred to as Euclidean distance method; Cayuela et al, 2019; Nathan et al, 2002; Pyšek & Hulme, 2005). However, it could often be misleading for landscape‐scaled dispersal events especially when the dispersal pathway and its structure in the matrix are explicitly known.…”

Individual contributions to group chorus dynamics influence access to mating opportunities in wood frogs

“…Although the means by which this fitness benefit evolves remains contested (e.g. kin selection; (Cayuela et al, 2019; Kokko & Lindstrom, 1996) but see (Lebigre et al, 2014)) leks represent another case in which a signal produced by groups directly influences the mating probability of individuals within that group. Like the study of group visual displays produced by lekking species, we have presented an investigation into how individual‐level variation in bioacoustic signals contribute to chorus dynamics and the subsequent probability of mating opportunities.…”