| Many insects produce stridulatory sounds which may function in both intra- and interspecific communication. Studies of stridulation in Coleoptera include descriptions of morphology of sound-producing structures, sound characteristics, and manipulations of sound production to discover its function. Here I present four studies that further our understanding of the role of sound in North American Nicrophorus, and suggest both practical and theoretical applications for understanding stridulation in behavioral and conservation contexts. In the first study, I characterize the sound produced by eight different Nicrophorus species, examining characteristics of both the signals and stridulatory apparati for variation across species, with analysis of relationships between sound and morphology. In the second study, I apply this knowledge to an aspect of conservation; specifically, whether structural damage to elytra affects the fecundity of the endangered American burying beetle, Nicrophorus americanus. Then, I address the use of sound as an intraspecific signal during contests for obligate breeding resources. And finally, I address the function of stridulation for reproductive behaviors and fecundity.;I found that induced Nicrophorus stridulations are biphastic and broadband with weak dominant frequency structure, and that sound and stridulatory structures differ among the eight species studied. These differences in sound do not relate to any of the morphological characters quantified in this study. In addition, structural alteration of the elytra changes the temporal characteristics of female N. americanus stridulation and results in reduced fecundity. Finally, removing sound does not influence contest outcomes in male N. marginatus; body size remains the best predictor of competitive ability. Removing sound does not affect reproductive success. The evidence presented in these studies indicates that stridulations are likely playing more of a role in interspecific communication, such as an aposematic warning signal, or possibly as an intraspecific aggregation signal between parent and offspring. Future investigations are focused on the sounds produced in the context of reproductive behaviors such as competition for resources, copulation and nest preparation, and brood care. |
