When an individual ascends in dominance status within their social community, they often undergo a suite of behavioural, physiological and neuromolecular changes. While these changes have been extensively characterized across a number of species, we know much less about the degree to which these changes in turn influence cognitive processes like associative learning, memory and spatial navigation. Here, we assessed male Astatotilapia burtoni , an African cichlid fish known for its dynamic social dominance hierarchies, in a set of cognitive tasks both before and after a community perturbation in which some individuals ascended in dominance status. We assayed steroid hormone (cortisol, testosterone) levels before and after the community experienced a social perturbation. We found that ascending males changed their physiology and novel object recognition preference during the perturbation, and they subsequently differed in social competence from non-ascenders. Additionally, using a principal component analysis we were able to identify specific cognitive and physiological attributes that appear to predispose certain individuals to ascend in social status once a perturbation occurs. These previously undiscovered relationships between social ascent and cognition further emphasize the broad influence of social dominance on animal decision-making. This article is part of the theme issue ‘The centennial of the pecking order: current state and future prospects for the study of dominance hierarchies’.

Mothers, fathers, and offspring regularly clash over how much care offspring receive. Offspring beg to solicit for more resources--but how much begging is rewarded can depend on who is listening. While both parents benefit from provisioning offspring, each would benefit from their partner shouldering more of the burden of care, leading to sexual conflict. Additionally, if the costs and benefits of provisioning differ by sex, parent-offspring conflict should vary by sex. How these evolutionary conflicts influence sex differences in parent-offspring communication is unknown. To determine whether the sexes differ in their response to offspring signals, we conducted a meta-analysis on 30 bird species, comparing responsiveness to social and physiological traits affecting conflict. We found that a species' typical pair bond strength predicts whether males or females respond more to offspring begging. In species with stable and/or monogamous bonds, and thus lower sexual and paternal-offspring conflict, males' provisioning effort is more strongly correlated with offspring begging than females'. The opposite holds for species with weak pair bonds: females respond more to begging, perhaps compensating for males' lower responsiveness. These results demonstrate that sex differences in parental care can arise via sex differences in parent-offspring communication, driven by evolutionary conflicts.

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