The Sexual Behavior of Intersexual Domestic Fowl

Abstract

The behavior of intersexual domestic fowl, resulting from estrogen injd. eggs, was studied by introducing the bird to a rooster, hen, or dummy hen mounted in the copulatory position. The [male][male] resulting from such eggs were variously feminized while the hens were little affected. They were arbitrarily grouped, on the basis of plumage, into 4 classes, from 1st essentially [male], to 4th, [female] . The birds were kept in pens of 5 to 9 individuals of both sexes. The peck order revealed a social hierarchy with the most masculine [male][male] at the top and the most feminine at the bottom. Normal roosters waltz to induce a newcomer to indicate its sex. If the newcomer is a receptive [female] , it squats for copulation. If a cf, it raises the neck hackles, signifying hostility, thereby initiating a fight. Preliminary copulation behavior is divided into successive stages, each recapitulating preceeding ones: (1) lowered wing, (2) waltz and stop, (3) waltz and circle, (4) waltz and grab, (5) copulation. Intersexual [male][male] show gradations from essentially normal masculine behavior patterns to neutral or inactive behavior, corresponding in general to the degree of masculinity of the plumage. In general, plumage class 4 individuals (the most feminine) seldom went beyond stage (1). Class 3 individuals seldom beyond stage (3). Class 2 individuals commonly performed action (4). Class 1 individuals copulated occasionally, fertile matings occurring only with some of these.