Ecology predicts life history evolution in birds

Although a number of studies describe current evolutionary patterns concerning lifehistory evolution, how historical changes in the way organisms interact with their environment have shaped life-history evolution still remains unresolved. In this study, I integrate prospective and retrospective comparative approaches to ask what ecological factors have driven current variation in lifespan of bird passerines. An analysis of >500 species suggest that lifespan is higher in cooperative breeders and in species that build the nest in more secure sites, consistent with the age-specific theory of life history evolution. A retrospective analysis further indicated that these two traits likely evolved through a Ornstein-Uhlenbeck evolutionary model with different optima for each selective regime. Specifically, transitions to cooperative breeding behavior and to nesting in less exposed sites resulted in changes towards longer lifespan optima. These results are the first evidence that ecological and behavioral changes produced in life history strategies in the past, and provide new insights to understand and predict current and future life-history evolutionary patterns.