NSF Award
1455949
The goal of this project is to understand the evolution of complex social evolution using, as a model species, the acorn woodpecker (Melanerpes formicivorus), a highly social bird common in the southwestern United States. Acorn woodpeckers live in family groups of up to 15 individuals containing a combination of "helpers"--young that remain in their natal group and help raise younger siblings--and multiple breeders of both sexes, a rare mating system known as polygynandry found in several primate species. Researchers will combine cutting edge tracking technology with long-term demographic data, experimental studies, and genetic analyses to understand why helpers sacrifice reproduction to feed young that are not their own, and why helpers vary so much in their willingness to help their parents raise other siblings. The project will involve the training of a postdoctoral associate, a Ph.D. student, and 36 - 60 undergraduate and recent postgraduate students who will participate in the field and laboratory aspects of the study. The lead researchers will communicate their findings to the public through publications, outreach activities of the Cornell Lab of Ornithology, and television documentaries.<br/><br/>The project will focus specifically on determining: (1) the extent to which provisioning behavior by helpers per se, rather than other behaviors unrelated to provisioning that helpers engage in on their territory, is responsible for the indirect fitness benefits gained by helpers that remain in their natal group; (2) whether individual variability in helping behavior is due to differences in the amount of time helpers spend away from their natal territory or differences in their provisioning effort while present at the territory; and (3) the role that direct fitness benefits such as experience gained by helping or "pay-to-stay" play in the evolution of provisioning behavior. These goals will be achieved by (i) combining over 40 years of continuous monitoring of a color-banded population in which parentage is assigned genetically; (ii) conducting behavioral watches of provisioning behavior; and (iii) deploying solar-powered "nanotags" that will allow researchers to continuously monitor the location of individuals in the population. The project will disentangle the fitness benefits and drivers of provisioning behavior by helpers, thus providing a new understanding of the evolution of this putatively altruistic behavior. Data associated with specific publications will be made available in Dryad, whereas the more general datasets acquired as part of the project will be archived either with the Network Information System (NIS) designed for the LTER program (when it is expanded to include other long-term projects) or, alternatively, as a collection within the iPlant Data Store funded by the NSF Division of Biological Infrastucture.
