A female's past experience with predators affects male courtship and the care her offspring will receive from their father.

Abstract

Differential allocation occurs when individuals adjust their reproductive investment based on their partner's traits. However, it remains unknown whether animals differentially allocate based on their partner's past experiences with predation risk. If animals can detect a potential mate's experience with predators, this might inform them about the stress level of their potential mate, the likelihood of parental effects in offspring and/or the dangers present in the environment. Using threespined stickleback (Gasterosteus aculeatus), we examined whether a female's previous experience with being chased by a model predator while yolking eggs affects male mating effort and offspring care. Males displayed fewer conspicuous courtship behaviours towards females that had experienced predation risk in the past compared with unexposed females. This differential allocation extended to how males cared for the resulting offspring of these matings: fathers provided less parental care to offspring of females that had experienced predation risk in the past. Our results show for the first time, to our knowledge, that variation among females in their predator encounters can contribute to behavioural variation among males in courtship and parental care, even when males themselves do not encounter a predator. These results, together with previous findings, suggest that maternal predator exposure can influence offspring development both directly and indirectly, through how it affects father care.