Negotiation between parents: Does the timing of mate loss affect female compensation in Nicrophorus vespilloides?

Facultative adjustments in care are usually interpreted as a form of negotiation between the parents over how much care each should provide. Previous research on the burying beetle, Nicrophorus vespilloides, shows that males but not females appear to adjust their levels of care following negotiation. However, the importance of negotiation is likely to decrease over the course of a breeding attempt, and thus the timing of mate removal might affect the degree to which females adjust their levels of care. We therefore performed an experimental study where we removed N. vespilloides males at different intervals; before the female was provided the resources needed for breeding, 24 h after receiving resources, at the time of larval hatching, or after the parental care period. We monitored the effects on levels of female care of the offspring when parental care is at its highest. We found that the timing of male removal had a significant effect on the time females spent maintaining the carcass, but not on the time females spent providing food for the offspring or processing carrion. Our findings suggest that, in N. vespilloides, female decisions about how much care to provide involves negotiation, although the importance of negotiation decreases towards the end of breeding attempts. © Brill Academic Publishers 2006.