Fitness, Reproductive Value, and Cole's Result

In an influential paper Cole (1954) concluded that "for an annual species, the absolute gain in intrinsic population growth which could be achieved by changing to the perennial reproductive habit would be exactly equivalent to adding one individual to the average litter size". The purpose of this paper is to point out that Cole's result and subsequent modifications, most notably by Charnov and Schaffer (1973), can best be understood as applications of the life history theorem regarding the equivalence of maximizing fitness and reproductive value.