→ and 1859 1860 1861 |
or both from a common parent-stock, and 1866 1869 1872 |
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→
Selection
. —
1859 1860 |
Selection.
—
1861 |
Principles of Selection anciently followed, and their Effects.
1866 1869 |
Principles of Selection anciently followed
,
and their Effects.
1872 |
|
→ action 1859 1860 1861 1866 |
and definite action 1869 1872 |
|
Ask, as I have asked, a celebrated raiser of Hereford cattle, whether his cattle might not have descended from
→and
he will laugh you to scorn. I have never met a pigeon, or poultry, or duck, or rabbit fancier, who was not fully convinced that each main breed was descended from a distinct species. Van Mons, in his treatise on pears and apples, shows how utterly he disbelieves that the several sorts, for instance a Ribston-pippin or Codlin-apple, could ever have proceeded from the seeds of the same tree. Innumerable other examples could be given. The explanation, I think, is simple: from long-continued study they are strongly impressed with the differences between the several races; and though they well know that each race varies slightly, for they win their prizes by selecting such slight differences, yet they ignore all general arguments, and refuse to sum up in their minds slight differences accumulated during many
generations. May not those naturalists who, knowing far less of the laws of inheritance than does the breeder, and knowing no more than he does of the intermediate links in the long lines of descent, yet admit that many of our domestic races
descended from the same parents — may they not learn a lesson of caution, when they deride the idea of species in a state of nature being lineal descendants of other species? |
→
Selection
. —
|
Let us now briefly consider the steps by which domestic races have been produced, either from one or from several allied species. Some
effect
be attributed to the direct
→action
of the external conditions of life, and some
to habit; but he would be a bold man who would account by such agencies for the differences
a dray and race horse, a greyhound and
a carrier and tumbler pigeon. One of the most remarkable features in our domesticated races
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