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 |
Dentro del libro
Resultados 6-10 de 100
Página 15
... animals or plants , which have not been ranked by competent judges as mere varieties , and by other competent judges as the descendants of aborigin- ally distinct species . If any marked distinction ex- isted between domestic races and ...
... animals or plants , which have not been ranked by competent judges as mere varieties , and by other competent judges as the descendants of aborigin- ally distinct species . If any marked distinction ex- isted between domestic races and ...
Página 16
... animals and plants having an extra- ordinary inherent tendency to vary , and likewise to withstand diverse climates . I do not dispute that these capacities have added largely to the value of most of our domesticated productions ; but ...
... animals and plants having an extra- ordinary inherent tendency to vary , and likewise to withstand diverse climates . I do not dispute that these capacities have added largely to the value of most of our domesticated productions ; but ...
Página 17
... animals , it seems to me unlikely , in the case of the dog - genus , which is distributed in a wild state throughout the world , that since man first appeared one single species alone should have been domesticated . In regard to sheep ...
... animals , it seems to me unlikely , in the case of the dog - genus , which is distributed in a wild state throughout the world , that since man first appeared one single species alone should have been domesticated . In regard to sheep ...
Página 27
... animal's or plant's own good , but to man's use or fancy . Some variations useful to him have probably arisen suddenly , or by one step ; many botanists , for instance , believe that the fuller's teasel , with its hooks , which cannot ...
... animal's or plant's own good , but to man's use or fancy . Some variations useful to him have probably arisen suddenly , or by one step ; many botanists , for instance , believe that the fuller's teasel , with its hooks , which cannot ...
Página 28
... animals . Breeders habitually speak of an animal's organisation as something quite plastic , which they can model almost as they please . If I had space I could quote numerous passages to this effect from highly com- petent authorities ...
... animals . Breeders habitually speak of an animal's organisation as something quite plastic , which they can model almost as they please . If I had space I could quote numerous passages to this effect from highly com- petent authorities ...
Otras ediciones - Ver todas
On the Origin of Species by Means of Natural Selection: or the Preservation ... Charles Darwin Vista previa limitada - 2023 |
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