The evolution of parental care, especially by males, is poorly understood in insects because it is so rare, and few studies exist on mating systems in monogamous species. Male and female burying beetles (Nicrophorus spp.) cooperate to bury small carcasses, establish and maintain a brood chamber, feed and guard offspring for extended periods of time. The PI's investigations to date suggest that the amount of paternal investment of N. orbicollis is dependent on a balance between the number of offspring reared by a deserting versus a care-giving male, the probability that the carcass will be taken over by another burying beetle and the brood killed, and the probability that a deserting male can find a new carcass and rear another brood instead of rearing the present brood. This study will investigate the probabilities for each of these factors on a natural population in Jaffrey, New Hampshire. Silphid beetles are a good choice of animal to use in the study of the evolution of parental care and monogamy because the principal factors affecting the number of young that can be raised can be quantified and manipulated in a simple manner that generates straight-forward results. Moreover, the proposed research is highly feasible because the beetles are abundant, easily reared and maintained in the laboratory and easy to observe in the field and under simulated-field conditions. All behavioral and ecological aspects if parental care and the results of this care can be quantified and related to each other as components of total reproductive strategy. The results will provide a detailed, holistic picture of the costs and benefits of providing extended parental investment and will contribute to our understanding of the evolutionary ecology of parental care.
