This week i have picked 2 articles about great tits and their cognitive abilities. Papers discuss individual variations and if having high cognitive abilities advantageous in every situation. I hope you will enjoy reading them. See you on Tuesday. I will bring fika.
Cognitive Ability Influences Reproductive Life History Variation in the Wild
Cognition has been studied intensively for several decades, but the evolutionary processes that shape individual variation in cognitive traits remain elusive. For instance, the strength of selection on a cognitive trait has never been estimated in a natural population, and the possibility that positive links with life history variation are mitigated by costs or confounded by ecological factors remains unexplored in the wild. We assessed novel problem-solving performance in 468 wild great tits Parus major temporarily taken into captivity and subsequently followed up their reproductive performance in the wild. Problem-solver females produced larger clutches than nonsolvers. This benefit did not arise because solvers timed their breeding better, occupied better habitats, or compromised offspring quality or their own survival. Instead, foraging range size and day length were relatively small and short, respectively, for solvers, suggesting that they were more efficient at exploiting their environment. In contaast to the positive effect on clutch size, problem solvers deserted their nests more often, leading to little or no overall selection on problem-solving performance. Our results are
consistent with the idea that variation in cognitive ability is shaped by contrasting effects on different life history traits directly linked to fitness.
Personality and problem-solving performance explain competitive ability in the wild
Abstract:Competitive ability is a major determinant of fitness, but why individuals vary so much in their competitiveness ! remains only partially understood. One increasingly prevalent view is that realized competitive ability varies because it represents alternative strategies that arise because of the costs associated with competitiveness. Here we use a population of great tits (Parus major) to explore whether individual differences incompetitive ability when foraging can be explained by two traits that have previously been linked to alternative behavioural strategies: the personality trait 'exploration behaviour' and a simple cognitive trait, 'innovative problem-solving performance'. We assayed these traits under standardized conditions in captivity and then measuredcompetitive ability at feeders with restricted access in the wild. Competitive ability was repeatable within individual males across days and correlated positively with exploration behaviour, representing the first such demonstration of a link between apersonality trait and both competitive ability and food intake in the wild. Competitiveability was also simultaneously negatively correlated with problem-solving performance; individuals who were poor competitors were good at problem-solving. Rather than being the result of variation in 'individual quality', our results support the hypothesis that individual variation in competitive ability can be explained by alte! rnative behavioural strategies.