Parental care and cooperation in the burying beetle Nicrophorus vespilloides

Abstract

In species that provide parental care, individuals must choose how to split their resources between caring for their current offspring and investing in their own reproductive potential. These decisions are made based on factors that shift the balance of costs and benefits associated with allocating resources to current or future reproduction. For parents providing uniparental care such factors relate to the value of the current brood and the likelihood of future reproduction. Females and males that cooperate to provide biparental care, must also consider factors that may influence the contribution of their partner. In this thesis, I explore what affects the level of care parents provide for their offspring and how females and males that provide biparental care balance their relative contribution in the burying beetle Nicrophorus vespilloides. I focus on four factors: previous reproductive allocation, nutritional state, social environment, and synchrony in the onset of care. First, I found that females provided the same level of care to a subsequent brood regardless of previous reproductive allocation and resource access, which suggests that neither affected future ability to provide care. Next, I found that females adjusted their level of care in response to both their own nutritional state and that of their partner and that these decisions were independent of their partner’s contribution, while males only responded to the contribution of their partner. Then, I found that parents provided a similar level of care regardless of the presence of female or male intruders. Finally, I found that males provided more care when the female and male started providing care asynchronously in comparison to when they started synchronously while females provided a similar level of care regardless