facilitating reproductive and metabolic functions (Nelson, 2000 ; Luine, 2008 ; Eisenegger et al., 2011 ). Levels of testosterone, for example, have been found to correlate with decision-making in situations involving risk and cooperation (Burnham, 2007 ; Apicella et al., 2008 ; Stanton et al., 2011
testosterone (see Wingfield et al., 1990; Archer, 2006).
Testosterone (T) is one of the major sex hormones produced by the Leydig cells of the testes in males, whereas the ovaries and placenta produce it in females (Dixson, 1998; Eisenegger et al., 2011). T is responsible for the development and maintenance
and general health (Fink et al., 2005 ; Rhodes et al., 2007 ).
1.2. Body odour and changes in testosterone levels
Testosterone (T) is one of the major sex hormones produced by the body; it is mainly synthesized by the Leydig cells in the testes in men, whereas the ovaries and placenta
Levels of the steroid hormone testosterone have been found to impact diverse features of cognition from spatial memory to decision-making regarding risk, both in humans and other animals. However less is known about whether closely-related species differ in their testosterone-cognition relationships in line with pressures shaping each species’ cognitive evolution. We therefore examined relationships between testosterone and cognition in two-closely related species that differ markedly in their social behaviour, cognition, and patterns of testosterone production: bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). We presented individuals of both species with a battery of 16 cognitive tasks and determined whether performance on these tasks correlated with average testosterone level. We found that among male chimpanzees, high levels of testosterone correlated with higher performance in numerous tasks, including tasks assessing spatial cognition and physical cognitive abilities more broadly. Meanwhile, in male bonobos we found no correlations between testosterone and performance on the cognitive tasks, and found no correlations in females of either species. Building on prior comparative research, these results suggest that bonobos and chimpanzees differ critically in the proximate mechanisms influencing their cognitive capacities, and that in particular the role of testosterone in shaping behaviour and cognition differs dramatically between the two species.
could reflect physical or psychological stress as well as physical energetic demands (Nelson & Kriegsfeld, 2016). The level of testosterone (T), which is linked to male reproductive physiology and behaviour, such as sexual maturity, aggression, competition for mates and sexual behaviour (Adkins
. nattereri treated with this hormone (Franco-Belussi et al., 2013 ). However, the effects of sex hormones on visceral pigmentation are not known. In addition, estradiol and testosterone can affect the pigmented cell of Rana pipiens in culture (Himes & Hadley, 1971 ). These hormones affect external
SINGING IN RELATION TO SOCIAL DOMINANCE AND TESTOSTERONE IN WHITE-THROATED SPARROWS by R.
HAVEN WILEY, W. H. PIPER1), MANEE ARCHAWARANON2) and ELIZABETH WYRICK THOMPSON3)
(Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280,
U.S.A.) (With 3 Figures) Summary
mediate across ecologically relevant environmental contexts in any species (Williams, 2008 ; Ketterson et al., 2009 ). Male guppy mating behavior is likely to be increased by the androgens testosterone (T) and 11-ketotestosterone (11KT) (Borg, 1994 ; Dzieweczynski et al., 2006 ; Hallgren et al., 2006
effect on social cognition, we might expect that the steroid hormone, testosterone, will instead strengthen representations of body ownership, given its established capacity to influence social functioning and inhibit empathy. Testosterone is critical in neurodevelopment and has important activational
Differential testosterone sensitivity of forelimb muscles of male leopard frogs, Rana pipiens: test of a model system D. G. Blackburn1, R. S. Darrell1,2, K. T. Lonergan1, R. P. Mancini1, C. A. Sidor1,3 1 Department of Biology, Life Sciences Center, Trinity College, Hartford, CT 06106 U.S.A. 2