In a troop of young birds the sexes are about evenly balanced, and, presumably, in the wild state this balance is not much disturbed. But there probably is a preponderance of hens, even in the wild state, for, in the breeding season, the cocks fight among themselves, occasionally with fatal results. In domestication, the preponderance of hens is no doubt greater, for cocks are not only killed by kicking at each other through wire fences, thus breaking their legs, but also occasionally by people they attack. In domestication, neither all cocks nor all hens come into season; but, as the cocks that are killed are among the most vigorous and mettlesome, the proportion also of hens that come into season is greater than that of cocks.
Unattached Hens.
When a cock is ready to breed, he pairs with one hen, and with her makes the nest. If they escape the intrusion of other hens, this state of monogamy continues, and chicks result; if they do not, polygamy will probably take place, almost always with disastrous consequences to the nest.
Now, there are other hens in season, and being in excess of the cocks (who have already mated), they are unattached, having no cock to mate with. They surrender to any cock, and are thus fertilised. So excited and overwrought are they, that tame hens will often squat on the approach of a man. Having no nests of their own (only one case of a hen unaided making a nest has come under my observation), they lay their eggs in other hens' nests, each generally keeping to the nest she first selects; or they drop their eggs at random about the veld, this habit no doubt helping to give rise to the old Biblical belief, persisting to the present day, that the Ostrich leaves her eggs in the sand to hatch by the heat of the sun.
Herein, I think, to a great extent lies the true explanation of the so-called association of several hens with one cock, giving rise to the idea of polygamy. The cock is polygamous, it would seem, not so much from any free choice of his own as because the hens are forced upon him.
