The Origin of Species by Means of Natural Selection: Or, the Preservation of Favored Races in the Struggle for Life, Volumen1D. Appleton, 1898 |
Dentro del libro
Resultados 1-5 de 13
Página 1
... the same object . I hope that I may be ex- cused for entering on these personal details , as I give them to show that I have not been hasty in coming to a decision . My work is now ( 1859 ) nearly finished ;. 1 INTRODUCTION.
... the same object . I hope that I may be ex- cused for entering on these personal details , as I give them to show that I have not been hasty in coming to a decision . My work is now ( 1859 ) nearly finished ;. 1 INTRODUCTION.
Página 23
... object and failed . The offspring from the first cross between two pure breeds is tolerably and sometimes ( as I have found with pigeons ) quite uniform in character , and everything seems simple enough ; but when these mon- grels are ...
... object and failed . The offspring from the first cross between two pure breeds is tolerably and sometimes ( as I have found with pigeons ) quite uniform in character , and everything seems simple enough ; but when these mon- grels are ...
Página 39
... object in view , to make a new strain or sub - breed , superior to anything of the kind in the country . But , for our purpose , a form of Selection , which may be called Unconscious , and which results from every one trying to possess ...
... object in view , to make a new strain or sub - breed , superior to anything of the kind in the country . But , for our purpose , a form of Selection , which may be called Unconscious , and which results from every one trying to possess ...
Página 99
... objects to agriculturists speaking of the potent effects of man's selection ; and in this case the individual differences given by nature , which man for some object selects , must of necessity first occur . Others have objected that ...
... objects to agriculturists speaking of the potent effects of man's selection ; and in this case the individual differences given by nature , which man for some object selects , must of necessity first occur . Others have objected that ...
Página 125
... object , and if the individuals be al- lowed freely to intercross , his work will completely fail . But when many men , without intending to alter the breed , have a nearly common standard of perfection , and all try to procure and ...
... object , and if the individuals be al- lowed freely to intercross , his work will completely fail . But when many men , without intending to alter the breed , have a nearly common standard of perfection , and all try to procure and ...
Otras ediciones - Ver todas
Términos y frases comunes
adapted advantage allied analogous animals and plants appear Asa Gray beak become bees believe birds breeds caudicle cause cells characters climate closely colour common crossed cuckoo degree descendants developed difficulty distinct species disuse divergence domestic animals domestic races doubt effects eggs existence extinct extremely facts favourable females flowers forms Fritz Müller genera genus giraffe gradations greater number groups habits Hence hermaphrodites hive-bee important increase inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ large number larger genera larvæ less males manner Melipona Mivart modified natural selection naturalists nearly nest occasionally offspring organisation organs origin Origin of Species parent perfect period pigeons pollen pollen-grains present preserved prey principle probably produced progenitor quadrupeds rank rarely Red Grouse relation remarked resemble rock-pigeon seeds sexes sexual selection slight stamens striped structure struggle supposed swimbladder tend tendency tion tree variability variations varieties vary widely wings young