It is currently accepted that most sex differences in brain and behavior do not result from
direct genomic actions, but develop following early exposure to a sexually differentiated …

The steroid hormone testosterone (T) plays a central role in the regulation of breeding in
males, because many physiological, morphological and behavioural traits related to …

Sex is ubiquitous and variable throughout the animal kingdom. Historically, scientists have
used reductionist methodologies that rely on a priori sex categorizations, in which two …

Highlights•Testosterone (T) is thought to integrate phenotypes that work well
together.•However, it is not clear how such integration is generated within the organism.•T …

Testosterone is a key hormone for the development of secondary sexual characters and
dimorphisms in behavior and morphology of male vertebrates. Because females often …

A sequence of behaviours which we call courtship initiates reproduction in a large number of
species. In vertebrates, as a component of male sexual behaviour courtship is strongly …

Males of many animal species perform specialized courtship behaviours to gain copulations
with females. Identifying physiological and anatomical specializations underlying …

Age has been suggested to be positively related to the quality of an individual. Accordingly,
information about age might be important for assessment in, for example, mate choice …

Organismal behavior, with its tremendous complexity and diversity, is generated by
numerous physiological systems acting in coordination. Understanding how these systems …

Superior physical competence is vital to the adaptive behavioural routines of many animals,
particularly those that engage in elaborate sociosexual displays. How such traits evolve …