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 62
Página 66
... adapted individuals , supposing that there is any variability in a favourable direction , will tend to propagate their kind in larger numbers than the less well adapted . If the numbers be wholly kept down by the causes just indicated ...
... adapted individuals , supposing that there is any variability in a favourable direction , will tend to propagate their kind in larger numbers than the less well adapted . If the numbers be wholly kept down by the causes just indicated ...
Página 112
... adapted to dark caverns . Another blind genus ( Anophthalmus ) offers this remarkable peculiarity , that the species , as Mr. Murray observes , have not as yet been found anywhere except in caves ; yet those which inhabit the several ...
... adapted to dark caverns . Another blind genus ( Anophthalmus ) offers this remarkable peculiarity , that the species , as Mr. Murray observes , have not as yet been found anywhere except in caves ; yet those which inhabit the several ...
Página 388
... adapted for the same functions . A good instance is afforded by the close resemblance of the jaws of the dog and Tasmanian wolf or Thylacinus , -animals which are widely sundered in the natural system . But this resemblance is confined ...
... adapted for the same functions . A good instance is afforded by the close resemblance of the jaws of the dog and Tasmanian wolf or Thylacinus , -animals which are widely sundered in the natural system . But this resemblance is confined ...
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