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 15
... species , we generally perceive in each domestic race , as already remarked , less uni- formity of character than in true species . Domestic races of the same species , also , often have a somewhat monstrous character ; by which I mean ...
... species , we generally perceive in each domestic race , as already remarked , less uni- formity of character than in true species . Domestic races of the same species , also , often have a somewhat monstrous character ; by which I mean ...
Página 16
... species . In the case of some other domesticated species , there is presumptive , or even strong evidence , that all the breeds have descended from a single wild stock . It has often been assumed that man has chosen for domestication ...
... species . In the case of some other domesticated species , there is presumptive , or even strong evidence , that all the breeds have descended from a single wild stock . It has often been assumed that man has chosen for domestication ...
Página 41
... species - Wide ranging , much diffused , and common species vary most - Species of the larger genera in any country vary more than the species of the smaller genera - Many of the species of the larger genera resemble varieties in being ...
... species - Wide ranging , much diffused , and common species vary most - Species of the larger genera in any country vary more than the species of the smaller genera - Many of the species of the larger genera resemble varieties in being ...
Página 43
... species present an inordinate amount of variation ; and hardly two naturalists can agree which forms to rank as species and which as varieties . We may instance Rubus , Rosa , and Hieracium amongst plants , several genera of insects ...
... species present an inordinate amount of variation ; and hardly two naturalists can agree which forms to rank as species and which as varieties . We may instance Rubus , Rosa , and Hieracium amongst plants , several genera of insects ...
Página 44
... species . Practically , when a naturalist can unite two forms together by others having inter- mediate characters , he treats the one as a variety of the other , ranking the most common , but sometimes the one first described , as the ...
... species . Practically , when a naturalist can unite two forms together by others having inter- mediate characters , he treats the one as a variety of the other , ranking the most common , but sometimes the one first described , as the ...
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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