Testosterone and aggression in male red jungle fowl.
We investigated the relationship between aggression, plasma testosterone level (T), and change in T in captive male red jungle fowl (Gallus gallus). T measured on day 1 of our experiment was positively correlated with T on day 8, suggesting that T remains constant in males when the social environment is stable. During aggressive encounters that escalated to include physical combat, males that attacked first (won) had increased T relative to their opponent. Males did not differ in T measured 1 week before the aggressive encounter. Our data suggest that an increase in T during aggression is associated with winning in escalated fights.
Johnsen
T S
TS
Department of Biology, University of California, Riverside 92521, USA.
Zuk
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M
D000374:Aggression / Q000502:physiology*; D000378:Agonistic Behavior; D000818:Animals; D001143:Arousal / Q000502:physiology; D001717:Birds / Q000502:physiology*; D004291:Dominance-Subordination; D008297:Male; D012931:Social Environment; D013045:Species Specificity; D013739:Testosterone / Q000097:blood*
D013739:Testosterone