Biology ETDs

Publication Date



Models of sexual conflict predict that diving beetles should respond morphologically and behaviorally during mating events to overcome the opposing sex. Morphological and behavioral adaptations may result from pressures by one sex to overcome resistance to mating attempts of the opposite sex. Morphological data supports an evolutionary arms race in diving beetles (Dytiscidae) exhibited in a series of adaptations attributable to sexual conflict between males and females. Males of certain Dytiscinae have sucker shaped adhesion setae on their front and mid tarsi to improve attachment to the females elytra prior to and during mating, whereas females have evolved grooves, ridges, and furrows in the elytra that appear to interfere with the adhesion of the male's suction cups before and during copulation. Behaviors to overcome the opposing sex have been confirmed in Dytiscus alaskanus, but mating behavior in general has yet to be documented in other species of diving beetles. Behavioral data from more species will help clarify the evolution of sexual conflict in diving beetles. In this study, the mating behaviors of two species of diving beetles, Thermonectus nigrofasciatus and Rhantus binotatus, were described. Thermonectus nigrofasciatus and Rhantus binotatus mating behaviors were consistent with the model of sexual conflict in that males appear to coerce copulation on females and females resist male mating attempts. This study provides additional behavioral data that will enhance our understanding of the evolution of mating and sexual conflict in diving beetles.




Dytiscidae, Mating behavior, Thermonectus nigrofasciatus, Rhantus binotatus

Document Type


Degree Name


Level of Degree


Department Name

UNM Biology Department

First Advisor

Miller, Kelly

First Committee Member (Chair)

Kodric-Brown, Astrid

Second Committee Member

Wolf, Blair