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As we see that those variations which, under domestication, appear at any particular period of life, tend to reappear in the offspring at the same period; for instance, in the shape, size and flavour of the seeds of the many varieties of our culinary and agricultural plants; in the caterpillar and cocoon stages of the varieties of the silkworm; in the eggs of poultry, and in the colour of the down of their chickens; in the horns of our sheep and cattle when nearly adult; so in a state of nature natural selection will be enabled to act on and modify organic beings at any age, by the accumulation of variations profitable at that age, and by their inheritance at a corresponding age.
It coincides with the domestication of the dog, an epoch in hunting-life. It embraces thousands of centuries. The appearance of arrow-heads indicates the invention of the bow, and the rise of man from a defensive to an offensive mode of life.
Owing to some remarks on this subject, made in my work 'On the Variation of Animals under Domestication, Mr. He finds that gold-fish were first reared in confinement during the Sung Dynasty, which commenced A.D. 960. In the year 1129 these fishes abounded.
Would that we all had an equal faculty of domestication! In such a beautiful world, and with so many comfortable surroundings, we ought to feel at home in any place we are called to be.
Lastly, and this seems to me by far the most important consideration, new races of animals and plants are produced under domestication by man's methodical and unconscious power of selection, for his own use and pleasure: he neither wishes to select, nor could select, slight differences in the reproductive system, or other constitutional differences correlated with the reproductive system.
The domestication of the species appears to have been accomplished at several different points in Asia and Europe. The forms which are found in eastern Asia differ from those which are kept in the western portion of the great continent, and may have their blood commingled with that of another species which is native in that part of the world.
"Well, then, I'll just trickle out before she begins. Good-night, sir," said Doctor Prance, who by this time had begun to appear to Ransom more susceptible of domestication, as if she had been a small forest-creature, a catamount or a ruffled doe, that had learned to stand still while you stroked it, or even to extend a paw.
In the case of strongly marked races of some other domesticated species, there is presumptive or even strong evidence that all are descended from a single wild stock. It has often been assumed that man has chosen for domestication animals and plants having an extraordinary inherent tendency to vary, and likewise to withstand diverse climates.
The documents obtained through the agency of her easy-tempered kinsman, the late Marquis de Rochebriant, and her subsequent domestication in the house of the von Rudesheims, all this it is needless to do more here than briefly recapitulate.
Animals vary in nature as well as under domestication from causes not yet well understood. The variations that were favorable to survival, Darwin argued, would secure the survival, through the passing on of these variations by heredity of the better adapted types of plants and animals.
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