Sexually selected traits are often assumed to convey information to conspecifics about the condition and genetic quality of an individual. However, sexually selected traits also are hypothesized to be among the most rapidly ...

Ample sperm production is essential for successful male reproduction in many species. The amount of sperm a male can produce is typically constrained by the size of his testes, which can be energetically expensive to grow ...

Offspring phenotypes are often influenced by natal habitats, and these locations are commonly determined by mothers. The location where mothers leave their offspring may have different implications for offspring at different ...