This paper presents the Adaptive Calibration Model (ACM), an evolutionary–developmental
theory of individual differences in the functioning of the stress response system. The stress …

Testosterone is often considered a critical regulator of aggressive behaviour. There is
castration/replacement evidence that testosterone indeed drives aggression in some …

Trade-offs and constraints are inherent to life, and studies of these phenomena play a
central role in both organismal and evolutionary biology. Trade-offs can be defined …

A large body of evidence indicates that individual differences in baseline concentrations of
testosterone (T) are only weakly correlated with human aggression. Importantly, T …

Fluctuations in abiotic and biotic conditions exist in almost all habitats (Dunlap, Loros, &
DeCoursey, 2004; Stevenson et al., 2015). Some fluctuations like the alternation between …

Behavior of wild vertebrate individuals can vary in response to environmental or social
factors. Such within-individual behavioral variation is often mediated by hormonal …

Largely based on pre-theory that ties high testosterone (T) to masculinity, and low T to
femininity, high T is mainly studied in relation to aggression, mating, sexuality, and …

The functions of rapid increases in testosterone seem paradoxical because they can occur
in response to different social contexts, such as male–male aggressive encounters and male …

Hormones coordinate the co-expression of behavioral, physiological, and morphological
traits, giving rise to correlations among traits and organisms whose parts work well together …

Testosterone concentrations fluctuate rapidly in response to competitive and aggressive
interactions, suggesting that changes in testosterone rather than baseline differences shape …