Doctoral Dissertation Research: Phenotypic and Genetic Benefits of Polyandry in an Arctiid Moth (Utetheisa Ornatrix)

Cornell Univ - State: Awds Made Prior May 2010, Ithaca NY

Investigators

Abstract

Phenotypic and genetic benefits of polyandry in an arctiid moth (Utetheisa ornatrix) Thomas Eisner Female insects are frequently promiscuous. Given that a single male can provide sufficient sperm to fertilize a female's entire complement of eggs, why do females take multiple partners? An obvious possibility is that they are thereby able to avoid the pitfalls of inbreeding. Whether or not they actually give preference to males of disparate genetic makeup, implying that they are able to compare sets of sperm, is a question that can be answered by determining the degree of inbreeding of insects in natural populations. The moth Utetheisa ornatrix offers the opportunity to look into these unknowns. The female of the moth can take as many as 23 partners in her 2-3 weeks of existence. Mating incidence can be determined by counting the sperm sac remnants in the female's mating chamber, and degree of relatedness of the individuals in the population can be assessed by microsatellite analyses. Degree of relatedness is usually ignored in studies of insects. In Utetheisa the ascertainment of genetic affinities could cast light on the determinant selective processes that molded the reproductive behavior of Utetheisa, and could lay the groundwork for similar inquiries with other insects.