Does female personality drive mate preference and reproduction in wild house mice?

Fragkiskos Darmis, Anja Guenther, Alexandros Vezyrakis 

Personality, consistent individual behavioural variation, shapes how individuals move and engage with their socioecological environment, potentially influencing how they assess and choose mates. This makes personality a potential target of sexual selection. Indeed, personality is linked to partner choice, pair formation and mating outcomes in both human and non-human animals. However, it remains unclear whether personality shapes mating outcomes through active mate choice, or indirectly, by shaping which individuals encounter one another. Distinguishing between these pathways requires tracking mate choice across its successive stages, from preference and selectivity to realised reproduction. Here, we studied wild house mice in controlled mate preference assays and observed their matings in large semi-natural populations, allowing us to disentangle the stages of mate choice and test whether patterns from controlled conditions hold under naturalistic ones. Personality predicted female selectivity only in the controlled assay and produced assortative mating only in semi-natural conditions. Personality thus shapes different stages of mating depending on socioecological context, with assortative mating arising from personality-dependent space use rather than active preference. More broadly, personality may shape not mate preference itself but the processes generating it, so assessing its role in sexual selection requires tracking the full pathway from preference to reproduction.