Mate assessment behavior is correlated to learning ability in female threespine sticklebacks

In many species, males signal quality with elaborate traits, but females often show inter-individual variation in preference for these traits. Choosing a mate requires multiple cognitive steps; therefore, cognitive style (how an individual processes information) likely influences the perception of sexual signals and ability to choose a high-quality mate. An important component of cognitive style is flexibility; cognitively flexible individuals are more perceptive to shifts in cues. We hypothesized that cognitively flexible individuals would acquire more information about potential mates, better discern between two quality-signaling traits, and thus be more discriminatory. Here, we show that mate assessment is correlated to other cognitive traits. Although we did not detect an effect of cognitive style on mate preference or discrimination, we found that female threespine sticklebacks Gasterosteus aculeatus that spent more time assessing potential mates (more responsive) in a dichotomous mate choice task reached both the initial and reversal learning criterion in a spatial learning task with fewer errors. However, these highly responsive females made more consecutive mistakes immediately at the beginning of the reversal phase, suggesting that they did not quickly adapt to the environmental change but instead rapidly formed strict routines during the learning task that were eventually reversible after repeated errors. Furthermore, we found evidence for condition-dependent mate preference, with larger females preferring the high-quality male. These are among the first results that illustrate how cognitive traits might influence mate choice, which has implications for the strength and direction of sexual selection.