On the Origin of Species by Means of Natural Selection: Or The Preservation of Favoured Races in the Struggle for LifeHumphrey Milford, Oxford University Press, 1923 - 454 páginas |
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Página 9
... instances ) , yet having their reproductive system so seriously affected by un- perceived causes as to fail in acting ... instance , the rabbit and ferret kept in hutches ) , showing that their repro- ductive system has not been thus ...
... instances ) , yet having their reproductive system so seriously affected by un- perceived causes as to fail in acting ... instance , the rabbit and ferret kept in hutches ) , showing that their repro- ductive system has not been thus ...
Página 11
... instance of the effect of use . Not a single domestic animal can be named which has not in some country drooping ... instances are given in Isidore Geoffroy St. Hilaire's great work on this subject . Breeders believe that long limbs are ...
... instance of the effect of use . Not a single domestic animal can be named which has not in some country drooping ... instances are given in Isidore Geoffroy St. Hilaire's great work on this subject . Breeders believe that long limbs are ...
Página 14
... instance , of the cabbage , in very poor soil ( in which case , however , some effect would have to be attributed to the direct action of the poor soil ) , that they would to a large extent , or even wholly , revert to the wild ...
... instance , of the cabbage , in very poor soil ( in which case , however , some effect would have to be attributed to the direct action of the poor soil ) , that they would to a large extent , or even wholly , revert to the wild ...
Página 15
... parent species . This point , if it could be cleared up , would be interesting ; if , for instance , it could be shown that the greyhound , bloodhound , terrier , spaniel , and bull - dog , which VARIATION UNDER DOMESTICATION 15.
... parent species . This point , if it could be cleared up , would be interesting ; if , for instance , it could be shown that the greyhound , bloodhound , terrier , spaniel , and bull - dog , which VARIATION UNDER DOMESTICATION 15.
Página 21
... - pigeon , they must have descended from at least seven or eight aboriginal stocks ; for it is im- possible to make the present domestic breeds by the crossing of any lesser number : how , for instance VARIATION UNDER DOMESTICATION 21.
... - pigeon , they must have descended from at least seven or eight aboriginal stocks ; for it is im- possible to make the present domestic breeds by the crossing of any lesser number : how , for instance VARIATION UNDER DOMESTICATION 21.
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Términos y frases comunes
accumulated adapted affinities allied species America amount analogous ancient appear Archipelago become bees believe birds breeds cause cells characters cirripedes climate closely allied colour common parent continuous crossed crustaceans degree difficulty distinct species divergence doubt embryo endemic Europe existing exterminated extinct extremely facts favourable fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hermaphrodites hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing land larvæ less living male mammals manner Marsupials migration modification modified descendants natural selection naturalists nearly nest oceanic islands offspring organisation perfect pigeons pistil plants pollen present principle probably produced progenitor ranked reciprocal crosses remarked resemble rock-pigeon rudimentary organs seeds sexual selection Silurian slight South America sterility structure struggle successive suppose swimbladder tend theory tion trees variability variation vary whole widely