On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for LifeEaston Press, 1976 - 470 páginas |
Dentro del libro
Resultados 1-3 de 47
Página 27
... favourable to man's obviously favourable , as freely giving the materials for selection to power of selection work on ; not that mere individual differences are not amply sufficient , with extreme care , to allow of the accumulation of ...
... favourable to man's obviously favourable , as freely giving the materials for selection to power of selection work on ; not that mere individual differences are not amply sufficient , with extreme care , to allow of the accumulation of ...
Página 80
... favourable variations arising . The mere lapse of time by itself does nothing , either for or against natural ... favourable for the production of new species . But we may thus deceive ourselves , for to ascertain whether a small ...
... favourable variations arising . The mere lapse of time by itself does nothing , either for or against natural ... favourable for the production of new species . But we may thus deceive ourselves , for to ascertain whether a small ...
Página 184
... favourable for their existence than the present time . Whatever the causes may have been , we can see that certain districts and times would have been much more favourable than others for the development of so large a quadruped as the ...
... favourable for their existence than the present time . Whatever the causes may have been , we can see that certain districts and times would have been much more favourable than others for the development of so large a quadruped as the ...
Contenido
VARIATION UNDER NATURE | 30 |
STRUGGLE FOR EXISTENCE | 45 |
NATURAL SELECTION | 59 |
Derechos de autor | |
Otras 13 secciones no mostradas
Otras ediciones - Ver todas
Términos y frases comunes
accumulated adapted admit affinities allied species America ancient appear beak become bees believe belonging birds breeds cause cells characters climate closely allied colour common progenitor continuous crossed crustaceans degree developed difficulty distinct species divergence doubt effects eggs embryo existing exterminated extinct extremely facts favourable fertilised fertility flowers formation forms fossil Fritz Müller genera genus geological geological period gradations greater number groups of species habits Hence hybrids hybrids produced important increase individuals inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ larvæ less living male mammals manner marsupials migration modified descendants natural selection naturalists nearly nest occasionally offspring organisation organs Origin of Species parent peculiar perfect pigeons pistil plants pollen present preserved principle probably produced quadrupeds ranked reciprocal crosses remarked resemblance rudimentary seeds slight South America stamens sterility structure struggle successive supposed swimbladder theory variability variations varieties vary whilst whole wings young