characters be ever so slight, has had its wild prototype. At this rate
there must have existed at least a score of species of wild cattle, as many
sheep, and several goats in Europe alone, and several even within Great
Britain. One author believes that there formerly existed in Great Britain
eleven wild species of sheep peculiar to it! When we bear in mind that
Britain has now hardly one peculiar mammal, and France but few distinct
from those of Germany and conversely, and so with Hungary, Spain, &c., but
that each of these kingdoms possesses several peculiar breeds of cattle,
sheep, &c., we must admit that many domestic breeds have originated in
Europe; for whence could they have been derived, as these several countries
do not possess a number of peculiar species as distinct parent-stocks? So
it is in India. Even in the case of the domestic dogs of the whole world,
which I fully admit have probably descended from several wild species, I
cannot doubt that there has been an immense amount of inherited variation.
Who can believe that animals closely resembling the Italian greyhound, the
bloodhound, the bull-dog, or Blenheim spaniel, &c.--so unlike all wild
Canidae--ever existed freely in a state of nature? It has often been
loosely said that all our races of dogs have been produced by the crossing
of a few aboriginal species; but by crossing we can get only forms in some
degree intermediate between their parents; and if we account for our
several domestic races by this process, we must admit the former existence
of the most extreme forms, as the Italian greyhound, bloodhound, bull-dog,
&c., in the wild state. Moreover, the possibility of making distinct races
by crossing has been greatly exaggerated. There can be no doubt that a
race may be modified by occasional crosses, if aided by the careful
selection of those individual mongrels, which present any desired
character; but that a race could be obtained nearly intermediate between
two extremely different races or species, I can hardly believe. Sir J.
Sebright expressly experimentised for this object, and failed. The
offspring from the first cross between two pure breeds is tolerably and
sometimes (as I have found with pigeons) extremely uniform, and everything
seems simple enough; but when these mongrels are crossed one with another
for several generations, hardly two of them will be alike, and then the
extreme difficulty, or rather utter hopelessness, of the task becomes
apparent. Certainly, a breed intermediate between two very distinct breeds
could not be got without extreme care and long-continued selection; nor can
I find a single case on record of a permanent race having been thus formed.
On the Breeds of the Domestic Pigeon. -- Believing that it is always best
to study some special group, I have, after deliberation, taken up domestic
pigeons. I have kept every breed which I could purchase or obtain, and
have been most kindly favoured with skins from several quarters of the
world, more especially by the Hon. W. Elliot from India, and by the Hon. C.
Murray from Persia. Many treatises in different languages have been
published on pigeons, and some of them are very important, as being of
considerably antiquity. I have associated with several eminent fanciers,
and have been permitted to join two of the London Pigeon Clubs. The
diversity of the breeds is something astonishing. Compare the English
carrier and the short-faced tumbler, and see the wonderful difference in
their beaks, entailing corresponding differences in their skulls. The
carrier, more especially the male bird, is also remarkable from the
wonderful development of the carunculated skin about the head, and this is
accompanied by greatly elongated eyelids, very large external orifices to
the nostrils, and a wide gape of mouth. The short-faced tumbler has a beak
in outline almost like that of a finch; and the common tumbler has the
singular and strictly inherited habit of flying at a great height in a
compact flock, and tumbling in the air head over heels. The runt is a bird
of great size, with long, massive beak and large feet; some of the
sub-breeds of runts have very long necks, others very long wings and tails,
others singularly short tails. The barb is allied to the carrier, but,
instead of a very long beak, has a very short and very broad one. The
pouter has a much elongated body, wings, and legs; and its enormously
developed crop, which it glories in inflating, may well excite astonishment
and even laughter. The turbit has a very short and conical beak, with a
line of reversed feathers down the breast; and it has the habit of
continually expanding slightly the upper part of the oesophagus. The
Jacobin has the feathers so much reversed along the back of the neck that
they form a hood, and it has, proportionally to its size, much elongated
wing and tail feathers. The trumpeter and laugher, as their names express,
utter a very different coo from the other breeds. The fantail has thirty
or even forty tail-feathers, instead of twelve or fourteen, the normal
number in all members of the great pigeon family; and these feathers are
kept expanded, and are carried so erect that in good birds the head and
tail touch; the oil-gland is quite aborted. Several other less distinct
breeds might have been specified.
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 number of the caudal and sacral vertebrae
vary; 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 wing and tail to each other and
to the body; the relative length of leg and of the feet; 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 differs remarkably; as does in some breeds the
voice and disposition. Lastly, in certain breeds, the males and females
have come to differ to a slight degree from each other.
Altogether at least a score of pigeons might be chosen, which if shown to
an ornithologist, and he were told that they were wild birds, would
certainly, I think, be ranked by him as well-defined species. Moreover, I
do not believe that any ornithologist would
place the English carrier, the
short-faced tumbler, the runt, the barb, pouter, and fantail in the same
genus; more especially as in each of these breeds several truly-inherited
sub-breeds, or species as he might have called them, could be shown him.
Great as the differences are between the breeds of pigeons, I am fully
convinced that the common opinion of naturalists is correct, namely, that
all have 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. 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? The supposed
aboriginal stocks must all have been rock-pigeons, that is, not breeding or
willingly perching 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
very 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. Hence the
supposed extermination of so many species having similar habits with the
rock-pigeon seems to me a very rash assumption. Moreover, the several
world, and, therefore, some of them must have been carried back again into
their native country; but not one has ever become wild or feral, though the
dovecot-pigeon, which is the rock-pigeon in a very slightly altered state,
has become feral in several places. Again, all recent experience shows
that it is most difficult to get any wild animal 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-civilized man, as to be quite
prolific under confinement.
An argument, as it seems to me, of great weight, and applicable in several
other cases, is, that the above-specified breeds, though agreeing generally
in constitution, habits, voice, colouring, and in most parts of their
structure, with the wild rock-pigeon, yet are certainly highly abnormal in
other parts of their structure: we may look in vain throughout 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. Hence it must be assumed not only that
half-civilized 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 seem to me improbable in the
highest degree.
Some facts in regard to the colouring of pigeons well deserve
consideration. The rock-pigeon is of a slaty-blue, and has a white rump
(the Indian sub-species, C. intermedia of Strickland, having it bluish);
the tail has a terminal dark bar, with the bases of the outer feathers
externally edged with white; the wings have two black bars; some
semi-domestic breeds and some apparently truly wild breeds have, besides
the two black bars, the wings chequered with black. These several marks do
not occur together in any other species of the whole family. Now, in every
one of the domestic breeds, taking thoroughly well-bred birds, all the
above marks, even to the white edging of the outer tail-feathers, sometimes
concur perfectly developed. Moreover, when two birds belonging to two
distinct breeds are crossed, neither of which is blue or has any of the
above-specified marks, the mongrel offspring are very apt suddenly to
acquire these characters; for instance, I crossed some uniformly white
fantails with some uniformly black barbs, and they produced mottled brown
and black birds; these I again crossed together, and one grandchild of the
pure white fantail and pure black barb was of as beautiful a blue colour,
with the white rump, double black wing-bar, and barred and white-edged
tail-feathers, as any wild rock-pigeon! We can understand these facts, on
the well-known principle of reversion to ancestral characters, if all the
domestic breeds have descended from the rock-pigeon. But if we deny this,
we must make one of the two following highly improbable suppositions.
Either, firstly, that all the several imagined aboriginal stocks were
coloured and marked like the rock-pigeon, although no other existing
species is thus coloured and marked, so that in each separate breed there
might be a tendency to revert to the very same colours and markings. Or,
secondly, that each breed, even the purest, has within a dozen or, at most,
within a score of generations, been crossed by the rock-pigeon: I say
within a dozen or twenty generations, for we know of no fact countenancing
the belief that the child ever reverts to some one ancestor, removed by a
greater number of generations. In a breed which has been crossed only once
with some distinct breed, the tendency to reversion to any character
derived from such cross will naturally become less and less, as in each
succeeding generation there will be less of the foreign blood; but when
there has been no cross with a distinct breed, and there is a tendency in
both parents to revert to a character, which has been lost during some
former generation, this tendency, for all that we can see to the contrary,
may be transmitted undiminished for an indefinite number of generations.
These two distinct cases are often confounded in treatises on inheritance.
Lastly, the hybrids or mongrels from between all the domestic breeds of
purposely made on the most distinct breeds. Now, it is difficult, perhaps
impossible, to bring forward one case of the hybrid offspring of two
animals clearly distinct being themselves perfectly fertile. Some authors
believe that long-continued domestication eliminates this strong tendency
to sterility: from the history of
the dog I think there is some
probability in this hypothesis, if applied to species closely related
together, though it is unsupported by a single experiment. But to extend
the hypothesis 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, seems to me rash in the extreme.
From these several reasons, namely, the improbability of man having
formerly got seven or eight supposed species of pigeons to breed freely
under domestication; these supposed species being quite unknown in a wild
state, and their becoming nowhere feral; these species having very abnormal
characters in certain respects, as compared with all other Columbidae,
though so like in most other respects to the rock-pigeon; the blue colour
and various marks occasionally appearing in all the breeds, both when kept
pure and when crossed; the mongrel offspring being perfectly fertile;--from
these several reasons, taken together, I can feel no doubt that all our
domestic breeds have descended from the Columba livia with its geographical
sub-species.
In favour of this view, I may add, firstly, that C. livia, or the
rock-pigeon, 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, although an English
carrier or short-faced tumbler differs immensely in certain characters from
the rock-pigeon, yet by comparing the several sub-breeds of these breeds,
more especially those brought from distant countries, we can make an almost
perfect series between the extremes of structure. Thirdly, those
characters which are mainly distinctive of each breed, for instance the
wattle and length of beak of the carrier, the shortness of that of the
tumbler, and the number of tail-feathers in the fantail, are in each breed
eminently variable; and the explanation of this fact will be obvious when
we come to 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 Aegyptian 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 20,000 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 be obvious when we treat of Selection. We shall then,
also, see how it is that the 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.
I have discussed the probable origin of domestic pigeons at some, yet quite
insufficient, length; because when I first kept pigeons and watched the
several kinds, knowing well how true they bred, I felt fully as much
difficulty in believing that they could ever have descended from a common
parent, as any naturalist could in coming to a similar conclusion in regard
to the many species of finches, or other large groups of birds, in nature.