The effects of ecological and social factors on life history trade-offs and sex differences in parental care in burying beetles
In this study, I investigate how social and ecological factors shape sex-specific parental care and life history trade-offs by using the burying beetle Nicrophorus vespilloides as a model system. I found that males and females differ fundamentally in their parental strategies. Females work near their physiological limit and consistently provide high levels of care, whereas males are more flexible, adjusting their effort in response to partner presence, brood size, and resource availability. These sex-specific roles lead to different reproductive costs: males pay through reduced future care, while females pay through immediate weight loss.I found that resource availability plays a crucial role in masking or revealing trade-offs. When resources are abundant, expected trade-offs—such as between current and future reproduction, or between offspring number and size—become undetectable. In contrast, limited resources intensify these trade-offs, making them clearly visible. I also show that a poor nutritional start during sexual maturation is not necessarily permanent. Individuals that experience early deficits can fully recover if they later gain access to abundant resources. This compensatory ability highlights the flexibility and resilience of life history strategies.
Overall, this research demonstrates that parental care strategies are sex-specific, highly plastic, and strongly influenced by environmental context. These findings advance our understanding of how animals balance investment between current and future offspring under changing conditions.