The Polynesian field cricket is native to northern Australia and the Pacific Islands, and has been introduced to Hawaii. Only in Hawaii it is subject to a parasitoid fly that finds its host by listening to the calling song of the male crickets and depositing larvae that burrow inside the cricket and eventually kill it. This puts the cricket in an evolutionary dilemma, because calling is his means to attract a mate, but also places him in danger. On the island of Kauai, where the proportion of males infested by the flies had been highest of the three Hawaiian Islands where the cricket and fly co-occur, nearly 90% of the male crickets now show a mutated wing that lacks the apparatus necessary for calling. They are thus unable to call, which protects them from the fly. This project examines the consequences of such extraordinarily rapid evolution (the change occurred over 16-20 generations) for the mating behavior of the crickets. The mutation and its effects will be monitored in the field, and laboratory experiments will examine the ways that males achieve mating success without calling. This research provides a compelling introduction to many topics in evolutionary biology and animal behavior because it features familiar animals - crickets - in an attractive place -Hawaii - evading an unpleasant "Alien"-like parasite via natural selection, which then places the males in a dilemma with regard to sex. In addition to providing valuable and exciting research opportunities for undergraduate and graduate students, the PI will mentor school students in math and science through the university's MESA program.
