Reproductive Conflicts And Signal Evolution In Social Wasps And Bees
Chapter 1 (published in Naturwissenshaften) is a side project on honeybee behavior. We showed that honeybee colonies that are headed by queens who are artificially inseminated with the sperm of a single drone have egg-eating policing behavior, just like colonies with naturally mated, highly polyandrous queens. Chapter 2 is an ESS-style model of worker reproduction in honeybee colonies, suggesting that workers may invest in selfish reproduction if they sense the queen may be about to die. Chapter 3 (published in BMC Evolutionary Biology) addresses the evolution of multiple mating in the Vespine wasps. First, I used microsatellite markers to describe how many patrilines are present in colonies of five wasp species, four of which are in the enigmatic Vespula rufa species group, and the last a facultative social parasite of another species of yellowjacket. I also performed a comparative analysis of paternity number and paternity skew across 21 species of yellowjacket wasps and hornets (Vespidae: Vespinae). Species with larger colonies have higher average paternity frequencies and lower average paternity skew, with interesting implications for the evolution of polyandry in this group. Chapters 4 and 5 focus on the adaptive significance of matricide in Dolichovespula arenaria, an aerially nesting yellowjacket wasp. I describe matricide for the first time in this species, and use experiments and genetic analyses to show that in natural and lab colonies, queens that are killed are typically those who have mated few times, or who use sperm in a strongly biased way, resulting in high worker relatedness. Queens who have mated multiply and use sperm evenly are rarely killed, supporting the hypothesis that workers kill queens as a result of conflict over the production of males. Experiments suggested that queens laying only male eggs do not trigger matricide, nor does an abrupt drop in queen fecundity, contrary to theoretical predictions. Chapter 6 examines the evolution of cuticular hydrocarbon diversity across the polistine wasps, and provides evidence that the diversity of recognition compounds correlates with social organization, suggesting that these compounds have evolved in response to their function in recognition behavior.
Social evolution; Reproductive conflict; Kin selection; Altruism; Social insects; Eusociality; Worker reproduction
Reeve,Hudson Kern; Sherman,Paul Willard; Gilbert,Cole
Ph. D., Behavioral Biology
Doctor of Philosophy
dissertation or thesis