Exploration and social environment affect inbreeding avoidance in a small mammal

Abstract

Individual exploration types are based on the cognitive speed-accuracy trade-off, which suggests that a higher speed of information acquisition is done by sacrificing information quality. In a mating context, fast exploration could thus increase the probability of finding mates at the cost of mating with kin or suboptimal partners. We tested this hypothesis by studying male mate choice patterns in a species with a scramble competition mating system. We used genotyping, localization by radio-collar, trapping, and repeated exploration measures from a long-term study on wild Eastern chipmunks (Tamias striatus). We predicted that, according to the speed-accuracy trade-off hypothesis, slower-thorough explorers should be choosier than faster-superficial ones, and thus avoid inbreeding. We found that slower males reproduced more often with less related females, but only on one site where variance in relatedness and female density were high. Males showed no preference for their mates’ exploration type. Our results suggest that superficial exploration decreases male choosiness and increases the risk of inbreeding, but only under decreased mate search costs due to high variance in relatedness among mates (at high density). Our findings reveal exploration-related, among-individual variance in inbreeding, highlighting the complexity of mate choice, and showing that many aspects of an individual’s life contribute to animal decision-making.