286: Kin selection and cooperative courtship in wild turkeys
Here I show, using genetic measures of relatedness and reproductive success, that kin selection can explain the evolution of cooperative courtship in wild turkeys. Subordinate (helper) males do not themselves reproduce, but their indirect fitness as calculated by Hamilton's rule more than offsets the cost of helping. This result confirms a textbook example of kin selection that until now has been controversial and also extends recent findings of male relatedness on avian leks by quantifying the kin-selected benefits gained by non-reproducing males.One of the great advances in evolutionary biology was the formalization of kin selection over the non-rigorous "group selection" that prevailed through the 60's. This research validates the evolutionary prediction that males will forgo reproduction to help a relative if the benefits to the family line outweigh the costs to the helper.
This is a sophisticated and non-obvious evolutionary hypothesis which is consistently borne out in the wild.