Having an urban life mean several challenges to organisms. Despite the central role of behavioral responses to cope with these challenges, whether or not endocrine traits contribute to explain the differential species behavioral response to urbanization remain unknown. To address the above question, we assembled a dataset of 385 corticosterone records across 55 avian species, which was combined with urban tolerance metrics and phylogenetic information by mean of a flexible Bayesian framework.
Results/Conclusions
We show that species that thrive in urban areas have lower -both baseline and peak- corticosterone levels, compared to species that avoid an urban life. This was independent on the life history stage of birds during the sampling of corticosterone. Interesting, big-brained urban tolerant birds shows higher corticosterone levels compared with small-brained urban avian species, which may be related to differential life history strategies of urban tolerant birds. By considered multiple species across several cities around the globe, we give for the first time a general support for the role of endocrine system on the behavioral adaptation to an urban life.