DISSERTATION RESEARCH: Understanding the Evolutionary Patterns Contributing to Species-specific Male and Female Genitalia in a Group of Scarab Beetles

University Of Connecticut, Storrs CT

Investigators

Abstract

The focus of this dissertation improvement grant is to address how species-specific male and female genitalia evolve in a group of scarab beetles. This is a diverse group of large, brown beetles comprised of approximately 250 species in North America which all look extremely similar upon initial examination of their external morphology. However, each species has unique male and female genitalia, which are used by taxonomists to distinguish them from close relatives. This research will elucide the relationships of a species complex within this group of scarab beetles from eastern regions of the United States. The inferred relationships will allow the investigators to test hypotheses of genitalic evolution of both male and female genital characters and determine whether male and female genitalia are evolving along similar trajectories. In addition, fertilization success analyses within one species will be conducted to determine whether intraspecific variation of male and female genitalic shapes is correlated with paternity success. These two aspects of the project will allow the investigators to determine whether evolutionary processes occurring among species are concordant with the evolutionary processes occurring within species. This research will provide the foundation necessary to empirically test the role genitalic evolution plays in the speciation and diversification of a polygamous insect group. This research will provide a graduate student with experience in the fields of animal behavior, molecular systematics, and morphometrics, and includes cross-university collaborations with researchers at Cornell, Dartmouth, and Amherst College. In addition, information and data compiled through this research will be used to develop a publicly accessible species database for this particular group of scarab beetles. In addition, all aspects of this research incorporate undergraduate assistants, and provides the opportunity for undergraduates to gain experience doing both field and lab work and to learn how to integrate data across multiple disciplines.