Learning to discriminate the sex of conspecifics in male Japanese quail (Coturnix coturnix japonica): tests of "biological constraints".

Male Japanese quail learn to approach and remain near female, but not male, quail if they are allowed to copulate with female quail and receive noncopulatory exposures to males. The generality of the mechanisms involved in this type of discrimination learning was investigated in the present study. In Experiment 1, Ss learned to spend more time near initially unfamiliar blonde quail than familiar brown female or male quail as a result of being allowed to copulate with the blonde, but not the brown, quail. In Experiment 2, Ss learned to respond more to nonreproductive male as compared with female quail as a result of being allowed to copulate with the males, but not with the females. The experiments provided some evidence of a bias favoring responding to females independent of copulatory reinforcement contingencies. However, the results also indicated remarkable plasticity of discrimination learning about species-specific sexual stimuli.