Effects of hormones on the aggressive behaviour and social organization of the scincid lizard, Sphenomorphus kosciuskoi.

In order to ascertain whether hormones influence social organization of lizards, caged Sphenomorphus kosciuskoi were studied both before and after treatment with testosterone, estradiol, adrenaline and thyroxine. Testosterone and estradiol increased aggressiveness in male lizards and caused shifts in dominance. Adrenaline caused a temporary increase in activity and agressiveness but no change in social structure. Thyroxine did not affect social behaviour.