Are the Effects of Use and Disuse Inherited?: An Examination of the View Held by Spencer and DarwinMacmillan, 1890 - 156 páginas |
Dentro del libro
Resultados 1-5 de 20
Página x
... SHORTENED BREASTBONE IN PIGEONS . SHORTENED FEET IN PIGEONS SHORTENED LEGS OF RABBITS BLIND CAVE ANIMALS · 49 53 55 62 64 • 70 70 • • 72 INHERITED HABITS . · 73 TAMENESS OF RABBITS . 76 MODIFICATIONS OBVIOUSLY ATTRIBUTABLE TO SELECTION ...
... SHORTENED BREASTBONE IN PIGEONS . SHORTENED FEET IN PIGEONS SHORTENED LEGS OF RABBITS BLIND CAVE ANIMALS · 49 53 55 62 64 • 70 70 • • 72 INHERITED HABITS . · 73 TAMENESS OF RABBITS . 76 MODIFICATIONS OBVIOUSLY ATTRIBUTABLE TO SELECTION ...
Página 14
... shortened jaws . If a similar change is really occurring in man , could it not be similarly explained by some factor , such as sexual selection , which might affect the outward appearance at the cost of less obvious defects or ...
... shortened jaws . If a similar change is really occurring in man , could it not be similarly explained by some factor , such as sexual selection , which might affect the outward appearance at the cost of less obvious defects or ...
Página 23
... shortened phrases which would otherwise have to be employed to indicate this great but nameless factor of evolution . tion of a variety " unworkable " ( p . NATURAL SELECTION NOT RUINOUS . 23 ALLEGED RUINOUS SELECTION EFFECTS OF NATURAL.
... shortened phrases which would otherwise have to be employed to indicate this great but nameless factor of evolution . tion of a variety " unworkable " ( p . NATURAL SELECTION NOT RUINOUS . 23 ALLEGED RUINOUS SELECTION EFFECTS OF NATURAL.
Página 51
... Shortened wings would then become advantageous because they would restrain fatal migratory tendencies or useless and perilous flights in which the birds that flew furthest would be most often carried away by storms and adverse winds ...
... Shortened wings would then become advantageous because they would restrain fatal migratory tendencies or useless and perilous flights in which the birds that flew furthest would be most often carried away by storms and adverse winds ...
Página 57
... shortened in the tame breeds of ducks by over 5 per cent . ( and in two breeds by over 8 per cent . ) although they have increased more than 28 per cent . in proportional weight.2 How can increased use simultaneously shorten and thicken ...
... shortened in the tame breeds of ducks by over 5 per cent . ( and in two breeds by over 8 per cent . ) although they have increased more than 28 per cent . in proportional weight.2 How can increased use simultaneously shorten and thicken ...
Otras ediciones - Ver todas
Términos y frases comunes
acquired characters acquired modifications alleged Animals and Plants appears artificial selection atavism attributed Aylesbury duck become birds bones breeds cause cent civilization concomitant variation Contemporary Review Crown 8vo cumulative Darwin Descent deterioration diminished diminution diseases domestic animals domestic rabbit duck effects of ancestral effects of disuse enlarged epilepsy evidence evil explanation eyes fact factor of evolution fancy pigeons father favoured Francis Darwin Francis Galton Galton gemmules guinea-pigs heredity Illustrations improvement incisors increased individual inherited effects inherited injuries inherited mutilations insects instances instincts jaws Lamarckian leg-bones legs lengthened muscles natural or artificial natural selection nervous neuter offspring organs Origin of Species pangenesis panmixia parents pigeons Plants under Domestication quasi-inheritance race Ray Lankester reduced wings relative reproductive elements sexual selection shortened Spencer spite of disuse spontaneous variations sternum structure suppose tameness teeth tend tendency theory thickened sole tion toes transmit true inheritance use-inheritance Variation of Animals weight Weismann wing-bones
Pasajes populares
Página 26 - For peculiar habits confined to the workers or sterile females, however long they might be followed, could not possibly affect the males and fertile females, which alone leave descendants. I am surprised that no one has hitherto advanced this demonstrative case of neuter insects, against the well-known doctrine of inherited habit, as advanced by Lamarck.