Diet influences life span in parrots (Psittaciformes)

Source: Jason Munshi-South, Gerald S. Wilkinson, 2006, The Auk pp. 108–118
Evolutionary hypotheses regarding longevity predict that life span should increase as extrinsic mortality rates decrease.
Specifically, a decline in age-specific survival and fertility should evolve and decrease life span in proportion to the magnitude of the mortality risk.

We examined these ideas using a new data set on maximum longevity, ecology, and life history of 162 parrot species (Psittaciformes). Parrots are generally long-lived but exhibit remarkable variation in life span between similar-sized genera, with particularly long-lived species occurring in the Cacatua, Calyptorhynchus, and Amazona. After controlling for both body size and phylogenetic ancestry using a phylogenetic supertree of all 352 parrot species, type of diet and communal roosting explain significant variation in parrot life span, but the influence of communal roosting is statistically dependent on an association with diet type. We suggest that extreme longevity in parrots has evolved in response to species-specific characteristics of diet, habitat, and behavior that influence extrinsic mortality rates.