The evolution of large body size in females: a critique of Darwin's "fecundity advantage' model

Data and arguments do not show conclusively that Darwin's fecundity-advantage hypothesis is invalid, but they do suggest that it may apply to only a limited set of species. The degree to which female reproduction is limited by energy availability may be an important determinant of the applicability of Darwin's model. The demonstration that clutch size increases with maternal size is therefore not a sufficient basis from which to infer that natural selection should favor large female body size. Empirically, sizes of adult females do not consistently shift relative to those of males in taxa showing a fecundity advantage to large maternal size compared with taxa lacking such a fecundity advantage. -from Author