Sex-specific effects of postnatal testosterone on lateralization in cichlid fish

Lateralization is a fundamental principle in the organization of brain and behaviour in humans and nonhuman animals. To what extent lateralization is, in addition to genetic factors, under the influence of testosterone, which would also explain sex differences in laterality, is the topic of a long-standing debate. This debate is partly hampered by confusion between […]

Plasma steroid concentrations change in response to sexual behavior in Bufo marinus

Steroid hormone concentrations change in response to social or environmental stimuli in many vertebrates. To test this phenomenon in an amphibian, we examined plasma androgen (A) and corticosterone (B) concentrations in male marine toads (Bufo marinus), a tropical species exhibiting intermale competition, amplectic clasping of females, and bouts of breeding behavior following rains. When males […]