Arrhenidia

ARRHENIDIA (from Greek arrhen-male and eidos-form), manifestation of male sexual characteristics in females. The phenomenon of A. is quite frequently manifested in female birds (chickens, pheasants, ducks and many others). Arrhenidic females may develop spurs (in chickens), have male feathers instead of female feathers, emit male vocalizations, and exhibit various other male characteristics. The male characteristics may be manifested to a greater or lesser degree. The female's plumage may be replaced by male plumage either over the entire body or only in certain areas. A. is most often found in old or sick females. Frequently, A. is characteristic of sterile females born from the crossing of parents of different species. A. can be reproduced artificially through experiments involving castration or transplantation of a testicle to a female (see Bisexuality, Hermaphroditism, Sex). It has been established that A. in birds depends on the decline in the internal secretory activity of the ovary, which is sometimes accompanied by the manifestation of the activity of male-type sex glands in the body of the arrhenidic female.