Equivalence of maximizing reproductive value and fitness in the case of reproductive strategies.

The proposed equivalence of maximizing reproductive value and fitness is examined for two model life histories. In the first instance, it is assumed that offspring are fledged before the start of the next breeding season. In this case the proposed equivalence is verified. In the second model, parents care for their progeny for more than 1 year. In this case the optimal reproductive expenditure at a particular age is shown to depend on both current reproductive value and the diminution in survival rates of previously conceived young still dependent on parental protection.