Low heritability in tool use skills in a wild vulture population

Tool use is widespread among animals and has been under intense study due to its prominence in human society and evolution. A lack of detailed genetic information for wild populations has perpetuated assumptions regarding associations between individual differences in tool use and cognition and learning processes. However, captive birds and mammals can use tools in the absence of opportunities for social learning, indicating a genetic basis. Here, we used animal models and relatedness analysis to disentangle the role played by genetics and learning in tool use in an insular population of a long-lived vulture, Neophron percnopterus. Our results show a low heritability in this behaviour, perhaps because of the low variability observed among birds. However, not all individuals used stones to break eggs, and those that did so behaved consistently. Importantly, there was no evidence of learning at the timescale considered. Our results suggest that repeatability in tool use within individuals may indicate a link with some personality traits, with strong evolutionary and ecological consequences.