On the origin of species by means of natural selection , or, The preservation of favoured races in the struggle for life / by Charles Darwin.

  • Darwin, Charles, 1809-1882.
Date:
1859
Catalogue details

Licence: Public Domain Mark

Credit: On the origin of species by means of natural selection , or, The preservation of favoured races in the struggle for life / by Charles Darwin. Source: Wellcome Collection.

    39/546 (page 31)
    Chap. I. SELECTION BY MAN. 3] a large extent some breeds of cattle and sheep. In order fully to realise what they have done, it is almost necessary to read several of the many treatises devoted to this subject, and to inspect the animals. Breeders habitually speak of an animal's organisation as some¬ thing quite plastic, which they can model almost as they please. If I had space I could quote numerous passages to this effect from highly competent authorities. Youatt, who was probably better acquainted with the works of agriculturists than almost any other individual, and who was himself a very good judge of an animal, speaks of the principle of selection as that which enables the agriculturist, not only to modify the character of his flock, but to change it altogether. It is the magician's wand, by means of which he may summon into life what¬ ever form and mould he pleases. Lord Somerville, speaking of what breeders have done for sheep, says:— It would seem as if they had chalked out upon a wall a form perfect in itself, and then had given it existence. That most skilful breeder, Sir John Sebright, used to say, with respect to pigeons, that he would produce any given feather in three years, but it would take him six years to obtain head and beak. In Saxony the im¬ portance of the principle of selection in regard to merino sheep is so fully recognised, that men follow it as a trade : the sheep are placed on a table and are studied, like a picture by a connoisseur ; this is done three times at intervals of months, and the sheep are each time marked and classed, so that the very best may ultimately be selected for breeding. What English breeders have actually effected is proved by the enormous prices given for animals with a good pedigree ; and these have now been exported to almost every quarter of the world. The improvement is by no means generally due to crossing different breeds ; Ф