In disposition the several races differ. Some races are very silent; others coo in a highly peculiar manner.
Although many different races have kept true in character during several centuries, as we shall hereafter more fully see, yet there is far more individual variability in the most constant breeds than in birds in a state of nature. There is hardly any exception to the rule that those characters vary most which are now most valued and attended to by fanciers, and which consequently are now being improved by continued selection. This is indirectly admitted by fanciers when they complain that it is much more difficult to breed high fancy pigeons up to the proper standard of excellence than the so-called toy pigeons, which differ from each other merely in colour; for particular colours when once acquired are not liable to continued improvement or augmentation. Some characters become attached, from quite unknown causes, more strongly to the male than to the female sex; so that we have in certain races, a tendency towards the appearance of secondary sexual characters (5/41. This term was used by John Hunter for such differences in structure between the males and females, as are not directly connected with the act of reproduction, as the tail of the peacock, the horns of deer, etc.) of which the aboriginal rock-pigeon displays not a trace.
ON THE ABORIGINAL PARENT-STOCK OF THE SEVERAL DOMESTIC RACES. HABITS OF LIFE. WILD RACES OF THE ROCK-PIGEON. DOVECOTE-PIGEONS. PROOFS OF THE DESCENT OF THE SEVERAL RACES FROM COLUMBA LIVIA. FERTILITY OF THE RACES WHEN CROSSED. REVERSION TO THE PLUMAGE OF THE WILD ROCK-PIGEON. CIRCUMSTANCES FAVOURABLE TO THE FORMATION OF THE RACES. ANTIQUITY AND HISTORY OF THE PRINCIPAL RACES. MANNER OF THEIR FORMATION. SELECTION. UNCONSCIOUS SELECTION. CARE TAKEN BY FANCIERS IN SELECTING THEIR BIRDS. SLIGHTLY DIFFERENT STRAINS GRADUALLY CHANGE INTO WELL-MARKED BREEDS. EXTINCTION OF INTERMEDIATE FORMS. CERTAIN BREEDS REMAIN PERMANENT, WHILST OTHERS CHANGE. SUMMARY.
The differences described in the last chapter between the eleven chief domestic races and between individual birds of the same race, would be of little significance, if they had not all descended from a single wild stock. The question of their origin is therefore of fundamental importance, and must be discussed at considerable length. No one will think this superfluous who considers the great amount of difference between the races, who knows how ancient many of them are, and how truly they breed at the present day. Fanciers almost unanimously believe that the different races are descended from several wild stocks, whereas most naturalists believe that all are descended from the Columba livia or rock-pigeon.
Temminck (6/1. Temminck 'Hist. Nat. Gen. des Pigeons' etc. tome 1 page 191.) has well observed, and Mr. Gould has made the same remark to me, that the aboriginal parent must have been a species which roosted and built its nest on rocks; and I may add that it must have been a social bird. For all the domestic races are highly social, and none are known to build or habitually to roost on trees. The awkward manner in which some pigeons, kept by me in a summer-house near an old walnut-tree, occasionally alighted on the barer branches, was evident. (6/2. I have heard through Sir C. Lyell from Miss Buckley, that some half-bred Carriers kept during many years near London regularly settled by day on some adjoining trees, and, after being disturbed in their loft by their young being taken, roosted on them at night.) Nevertheless, Mr. R. Scot Skirving informs me that he often saw crowds of pigeons in Upper Egypt settling on low trees, but not on palms, in preference to alighting on the mud hovels of the natives. In India Mr. Blyth (6/3. 'Annals and Mag. of Nat. Hist.' 2nd series volume 20 1857 page 509; and in a late volume of the 'Journal of the Asiatic Society.') has been assured that the wild C. livia, var. intermedia, sometimes roosts in trees.