Reverting to the Wild State

Our domestic varieties, when run wild, gradually but certainly revert in character to their aboriginal stocks.

Hence it has been argued that no deductions can be drawn from domestic races to wild ones.

I have in vain endeavoured to discover on what decisive facts the above statement has so often and so boldly been made.

There would be great difficulty in proving its truth: we may safely conclude that

Very many of the most strongly-marked domestic varieties could not possibly live in the wild.

In many cases, we do not know what the aboriginal stock was. And so could not tell whether the animal or plant reverted.

In order to prevent the effects of intercrossing, only a single variety should be turned loose in its new home.

Our domesticated varieties occasionally revert in some of their characters to ancestral forms.

If we grew cabbage in very poor soil for many generations, they would partly or wholly revert to the wild aboriginal stock.

Whether or not the experiment would succeed, is not of great importance for our line of argument; for by the experiment itself the conditions of life are changed.

Reverting to the wild state is when species lose their acquired characters a while in unchanged domestic conditions in a large scale and freely breeding with each other.

If our domestic varieties reverted while domesticated then domestication means nothing to the species.

But there is no evidence in favour of this.

When the conditions of life do change in the wild, variations and reversions of character occur.

But natural selection will determine how far the new characters are preserved.

Most domestic races are judged as:

• mere varieties and
• the descendants of aboriginally distinct wild species.

Sometimes there is a marked distinction between domestic races and wild species.

Domestic races do not differ from each other in characters of generic value.

I think it could be shown that this statement is hardly correct;

But naturalists differ most widely in determining what characters are of generic value;

All such valuations being at present empirical.

We doubt the amount of structural difference between the domestic races of the same species because we do not know whether they have descended from one or several parent-species.

We can doubt the immutability of the many very closely allied and natural species if we could prove that the greyhound, bloodhound, terrier, spaniel, and bull-dog were the offspring of any single species.

• They would be simmilar to the foxes from different parts of the world.

I do not believe that all our dogs have descended from one wild species.

But, in the case of some other domestic races, there is strong evidence in favour of this view.

People have assumed that early humans have chosen for domestication the organisms that can vary and withstand diverse climates.

But how could a savage know, when he first tamed an animal, whether it would vary in succeeding generations, and endure other climates?

If other organisms, equal in number to our domesticated productions, and belonging to equally diverse classes and countries, were taken from the wild, and were bred for an equal number of generations under domestication, they would vary on an average as largely as the parent species of our existing domesticated productions have varied.

I do not know whether most of our anciently domesticated orgnisms come from one or several species.

Mr. Horner’s research have made it probable that civilized man existed in the Nile valley 14,000 years ago. They could have a semi-domestic dog in Egypt.

Our domestic dogs probably have descended from several wild species. But I do not know about sheep and goats.

Mr. Blyth studied the habits, voice, and constitution, &c., of the humped Indian cattle. These had descended from a different aboriginal stock from our European cattle. Several competent judges believe that these latter have had more than one wild parent.

I think that:

• all horses descended from one wild stock.
• all ducks and rabbits came from the common wild duck and rabbit.

Mr. Blyth thinks that all the breeds of poultry came from the common wild Indian fowl (Gallus bankiva).

The doctrine of the origin of our several domestic races from several aboriginal stocks, has been carried to an absurd extreme by some authors.

They believe that every race which breeds true, let the distinctive 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 11 wild species of sheep peculiar to it!

Britain has now hardly one peculiar mammal.

France has but few distinct from those of Germany and conversely, and so with Hungary, Spain, &c.

Each of these countries has several peculiar breeds of cattle, sheep, &c.

We must admit that many domestic breeds have originated in Europe.

The domestic dogs of the whole world probably descended from several wild species.

But 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;

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;

I do not believe that a race could be obtained nearly intermediate between two extremely different races or species.

Sir J. Sebright expressly experimentised for this and failed.

The offspring from the first cross between two pure breeds is tolerably and sometimes (as I have found with pigeons) extremely uniform.

But when these mongrels are crossed one with another for several generations, hardly two of them will be alike.

Then the extreme difficulty and 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.