Evolutionary theory is one of the most wide-ranging and inspiring scientific ideas, and it
offers a battery of methods that can be used to interpret human behaviour. However …

Although maternal dominance and good condition are frequently associated with raised
offspring sex ratios in mammals, the key factor may be female testosterone, which not only …

Inclusive fitness theory has been very successful in predicting and explaining much of the
observed variation in the reproductive characteristics of insect societies. For example, the …

Evolutionary theory predicts that mothers of different condition should adjust the birth sex
ratio of their offspring in relation to future reproductive benefits. Published studies …

When the relative fitness of male and female offspring varies with environmental conditions,
evolutionary theory predicts that parents should adjust the sex of their offspring accordingly …

Trivers and Willard's suggestion that natural selection favors maternal control of offspring
sex ratio in relation to maternal condition has been much debated. The theoretical …

Mammalian females pay high energetic costs for reproduction, the greatest of which is
imposed by lactation. The synthesis of milk requires, in part, the mobilization of bodily …

Lactation represents the greatest postnatal energetic expenditure for human and non‐
human primate females, and the ability to sustain the costs of lactation is influenced by a …

Adaptive theory predicts that mothers would be advantaged by adjusting the sex ratio of their
offspring in relation to their offspring's future reproductive success. Studies investigating sex …

Abstract Objectives Interbirth intervals (IBIs) are a key metric of female reproductive success;
understanding how they are regulated by environmental, social, and demographic factors …