I once came across a nest of this little dove in a low, prickly bush beside a small canal distributory, three miles outside Lahore. The dove appeared to have used as the foundation for its nest an old one of the striated bush babbler (_Argya caudata_). (I object to calling this bird the common babbler, since, like common sense, it is not very common.) In the same bush, at the same level, that is to say, about a yard from the ground and only a couple of feet from the dove’s nest, was that of a striated bush babbler containing three dark blue eggs. This is a case upon which those who believe that eggs laid in open nests are protectively coloured would do well to ponder.
There, side by side, in precisely the same environment, were two nests—one containing white and the other dark blue eggs. Obviously both sets of eggs could not be protectively coloured; as a matter of fact, both clutches of eggs were conspicuous objects. It not infrequently happens that the Indian robin (_Thamnobia cambayensis_), which lays white eggs thickly spotted with reddish brown, brings up a family in a disused nest of a striated bush babbler’s. The eggs of this latter are dark blue. It is surely time that zoologists gave up throwing at us their everlasting theory of protective colouring. If this were a _sine qua non_ of the safety of birds’ eggs, then the whole dove tribe would, long ago, have ceased to exist.
This family presents the ornithologist with yet another problem in colouration. In every species, except the red turtle-dove (_Oenopopelia tranquebarica_), both sexes are coloured alike. In this latter, however, there is very pronounced sexual dimorphism. The ruddy wing feathers of the cock enable one to distinguish him at once from his mate and from every other dove. Now the habits of this dove appear to be exactly like those of all other species. It constructs the same kind of nest and in similar situations; why then the sexual dimorphism in this species and in no other species? If the lady rufous turtle-dove likes nice ruddy wings, and thus the red wing has been evolved in the cock bird, why has she too not inherited it? I presume that even the most audacious Neo-Darwinian will not talk about her greater need of protection when sitting on the nest, for if she needs protection, how much more so do her white eggs? Further, it is my belief that the cock bird takes his turn in the incubation.