Links Between Cognition and Fitness: Mechanisms and Constraints in the Wild

Animals face constant environmental variations, with recent accelerating rates of anthropogenic change leading to mass habitat destruction and climate change on an unprecedented scale. To cope with rapid changes, animals must quickly adjust their decisions to new environmental conditions. Cognitive abilities can allow animals to exploit their environment better and/or more safely, gather and/or process information more efficiently, and adapt current behaviors and/or incorporate novel ones into their behavioral repertoires, thereby facilitating optimal responses to environmental changes. Cognitive abilities can thus be expected to be a key component of animal fitness in the wild and can shape the potential for animal populations to adapt to a changing world. Although a growing number of studies have recently explored the links between cognitive performances and fitness components, the results were not always in line with such a prediction: overall, cognitive performances and fitness components can show positive links, negative links, no links, or links dependent on the context or fitness components (suggesting trade-offs). Moreover, whether the links, when detected, are causal or due to indirect relations of cognitive abilities and fitness components with a third variable remains unknown in most cases. Identifying the mechanisms underlying the links between cognitive performances and fitness components and the constraints acting on these mechanisms is crucial to understand and predict how selective pressures can shape the evolution of cognitive abilities in the wild. This is a major gap in our understanding about how and when cognition can help animals adapt to their changing environments.

Both individual, non-cognitive traits (e.g. age, sex, personality, social status) and environmental factors (e.g. predation, parasitism, altitude, urbanization, food availability) can partly explain inter-individual variations in cognition, and could act on links with fitness. Clear tests of these effects are now needed to understand the conditions in which they impact the links between cognitive abilities and fitness components, which fitness components may be impacted and when, whether trade-offs between fitness components lead to favoring different cognitive strategies in different situations, and how different factors may interact to shape the evolutionary potential of cognitive abilities. In this Research Topic, we aim to explore how individual (behavioral, physiological, neurological, ontogenic, genetic) and environmental (social, natural and human-induced) factors interact and relate to proximate mechanisms shaping selective pressures on cognitive traits.