Question

As an offspring matures and becomes better able to care for itself, the benefit:cost (B:C) ratio–benefit to the offspring of continued parental care relative to cost in reproductive output to the parents–decreases. Over what range of B:C ratios is there a period of conflict between interest of parents and offspring?

1) 0.0 - 0.25
2) 0.25 - 0.5
3) 0.5 - 1.0
4) 1.0 - 2.0

Answer 1

Parent-offspring conflict over the B:C ratio of parental care occurs when the ratio is between 0.5 - 1.0. In this range, parents weigh the benefits of care against its costs to their reproductive success. Species' strategies vary based on their fecundity and the energy trade-offs they have evolved.

Step-by-step explanation:

The period of conflict between the interests of parents and offspring over the benefit: cost (B:C) ratio of parental care is when the ratio falls between 0.5 - 1.0. This range represents a threshold where the benefits of parental care to the offspring are equal to or greater than the costs to the parents. Below a ratio of 0.5, parental care may be deemed too costly relative to its benefits, potentially causing parents to favor ending care to increase their overall reproductive success. Above a ratio of 1.0, the benefits to the offspring outweigh the costs to the parents, which typically reduces parental-offspring conflict over the provision of care.

Species with low fecundity invest more in parental care, balancing the risk to the species' survival if a single offspring dies. Conversely, species that produce many offspring, like many marine invertebrates, often provide minimal parental care as their energy budget is dedicated to maximizing reproductive output. This strategy aids in the offspring's survival through quantity, despite their heightened vulnerability to predation.