01 - Variations Under Domestication

01-08 - Breeds of the Domestic Pigeons, their Differences and Origin

In the skeletons of the several breeds, the development of the bones of the face in length and breadth and curvature differs enormously.

The shape, as well as the breadth and length of the ramus of the lower jaw, varies in a highly remarkable manner.

The caudal and sacral vertebrae vary in number; as does the number of the ribs, together with their relative breadth and the presence of processes.

The size and shape of the apertures in the sternum are highly variable; so is the degree of divergence and relative size of the two arms of the furcula.

The proportional width of the gape of mouth, the proportional length of the eyelids, of the orifice of the nostrils, of the tongue (not always in strict correlation with the length of beak), the size of the crop and of the upper part of the oesophagus; the development and abortion of the oil-gland; the number of the primary wing and caudal feathers; the relative length of the wing and tail to each other and to the body; the relative length of the leg and foot; the number of scutellae on the toes, the development of skin between the toes, are all points of structure which are variable.

The period at which the perfect plumage is acquired varies, as does the state of the down with which the nestling birds are clothed when hatched.

The shape and size of the eggs vary.

The manner of flight, and in some breeds the voice and disposition, differ remarkably.

Lastly, in certain breeds, the males and females have come to differ in a slight degree from each other.

01 - Variations Under Domestication

01-08 - Breeds of the Domestic Pigeons, their Differences and Origin

Great as are the differences between the breeds of the pigeon, I am fully convinced that the common opinion of naturalists is correct, namely, that all are descended from the rock-pigeon (Columba livia), including under this term several geographical races or sub-species, which differ from each other in the most trifling respects.

Rock Pigeon

As several of the reasons which have led me to this belief are in some degree applicable in other cases, I will here briefly give them. If the several breeds are not varieties, and have not proceeded from the rock-pigeon, they must have descended from at least seven or eight aboriginal stocks; for it is impossible to make the present domestic breeds by the crossing of any lesser number: how, for instance, could a pouter be produced by crossing two breeds unless one of the parent-stocks possessed the characteristic enormous crop?

Pouter Pigeon

The supposed aboriginal stocks must all have been rock-pigeons, that is, they did not breed or willingly perch on trees.

But besides C. livia, with its geographical sub-species, only two or three other species of rock-pigeons are known; and these have not any of the characters of the domestic breeds.

Hence the supposed aboriginal stocks must either still exist in the countries where they were originally domesticated, and yet be unknown to ornithologists; and this, considering their size, habits, and remarkable characters, seems improbable; or they must have become extinct in the wild state.

But birds breeding on precipices, and good fliers, are unlikely to be exterminated; and the common rock-pigeon, which has the same habits with the domestic breeds, has not been exterminated even on several of the smaller British islets, or on the shores of the Mediterranean.

Mediterranean

Hence the supposed extermination of so many species having similar habits with the rock-pigeon seems a very rash assumption.

Moreover, the several above-named domesticated breeds have been transported to all parts of the world, and, therefore, some of them must have been carried back again into their native country; but not one has become wild or feral, though the dovecot-pigeon, which is the rock-pigeon in very slightly altered state, has become feral in several places.

Again, all recent experience shows that it is difficult to get wild animals to breed freely under domestication, yet on the hypothesis of the multiple origin of our pigeons, it must be assumed that at least seven or eight species were so thoroughly domesticated in ancient times by half-civilised man, as to be quite prolific under confinement.

An argument of great weight, and applicable in several other cases, is, that the above-specified breeds, though agreeing generally with the wild rock-pigeon in constitution, habits, voice, colouring, and in most parts of their structure, yet are certainly highly abnormal in other parts; we may look in vain through the whole great family of Columbidae for a beak like that of the English carrier, or that of the short-faced tumbler, or barb; for reversed feathers like those of the Jacobin; for a crop like that of the pouter; for tail-feathers like those of the fantail.

Rock Pigeon

English Carrier Pigeon

Short Faced Tumbler Pigeon

Barb Pigeon

Jacobin Pigeon

Pouter Pigeon

Fantail Pigeon

Hence it must be assumed not only that half-civilised man succeeded in thoroughly domesticating several species, but that he intentionally or by chance picked out extraordinarily abnormal species; and further, that these very species have since all become extinct or unknown.

So many strange contingencies are improbable in the highest degree.

01 - Variations Under Domestication

01-08 - Breeds of the Domestic Pigeons, their Differences and Origin

Lastly, the hybrids or mongrels from between all the breeds of the pigeon are perfectly fertile, as I can state from my own observations, purposely made, on the most distinct breeds.

Now, hardly any cases have been ascertained with certainty of hybrids from two quite distinct species of animals being perfectly fertile.

Some authors believe that long-continued domestication eliminates this strong tendency to sterility in species.

From the history of the dog, and of some other domestic animals, this conclusion is probably quite correct, if applied to species closely related to each other.

But to extend it so far as to suppose that species, aboriginally as distinct as carriers, tumblers, pouters, and fantails now are, should yield offspring perfectly fertile inter se, would be rash in the extreme.

Rock Pigeon

Dog

01 - Variations Under Domestication

01-08 - Breeds of the Domestic Pigeons, their Differences and Origin

In favour of this view, I may add, firstly, that the wild C. livia has been found capable of domestication in Europe and in India; and that it agrees in habits and in a great number of points of structure with all the domestic breeds.

Secondly, that, although an English carrier or a short-faced tumbler differs immensely in certain characters from the rock-pigeon, yet that, by comparing the several sub-breeds of these two races, more especially those brought from distant countries, we can make, between them and the rock-pigeon, an almost perfect series; so we can in some other cases, but not with all the breeds.

Thirdly, those characters which are mainly distinctive of each breed are in each eminently variable, for instance the wattle and length of beak of the carrier, the shortness of that of the tumbler, and the number of tailfeathers in the fantail; and the explanation of this fact will be obvious when we treat of Selection.

Fourthly, pigeons have been watched and tended with the utmost care, and loved by many people.

They have been domesticated for thousands of years in several quarters of the world; the earliest known record of pigeons is in the fifth Egyptian dynasty, about 3000 B.C., as was pointed out to me by Professor Lepsius; but Mr. Birch informs me that pigeons are given in a bill of fare in the previous dynasty.

In the time of the Romans, as we hear from Pliny, immense prices were given for pigeons; "nay, they are come to this pass, that they can reckon up their pedigree and race."

Pigeons were much valued by Akber Khan in India, about the year 1600; never less than 90,000 pigeons were taken with the court.

"The monarchs of Iran and Turan sent him some very rare birds"; and continues the courtly historian, "His Majesty by crossing the breeds, which method was never practised before, has improved them astonishingly."

About this same period the Dutch were as eager about pigeons as were the old Romans.

The paramount importance of these considerations in explaining the immense amount of variation which pigeons have undergone, will likewise be obvious when we treat of Selection. We shall then, also, see how it is that the several breeds so often have a somewhat monstrous character.

It is also a most favourable circumstance for the production of distinct breeds, that male and female pigeons can be easily mated for life; and thus different breeds can be kept together in the same aviary.

aviary