Cognitive abilities show distinct developmental trajectories in wild meerkats.

Understanding cognitive development is fundamental for explaining variation in adult cognitive phenotypes, and thus the processes driving cognitive evolution. The ontogeny of cognitive traits is likely influenced by both population-wide pressures, such as ecological demands, and individual-specific factors, including early life experiences. To properly investigate cognitive variation, we must therefore identify species-level developmental trajectories and individual variation from normative ontogeny. We studied the ontogeny of three cognitive traits-inhibition control, spatial cognition and physical problem-solving skills-in 41 wild meerkats (Suricata suricatta) from 12 litters (10 groups). Our longitudinal study followed individuals from early life to nutritional independence and into sub-adulthood. We found that rates of development (learning curves) varied among traits. Performance of cognitive traits did not correlate over ontogeny nor at specific time points, suggesting independent processes underlying each measured trait. While inhibitory control showed little individual variation in its development, spatial cognition and physical problem-solving showed substantive individual differences. Furthermore, physical problem-solving showed consistency in performance over time, a pattern that emerged near nutritional independence, reflecting its ecological importance early in life. Future research should determine the drivers of individual developmental variation and how such differences translate into fitness consequences.