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 82
Página vi
... animals and plants - Nature of the checks to increase - Com- petition universal - Effects of Climate - Protection from the number of individuals - Complex relations of all animals and plants throughout nature - Struggle for life most ...
... animals and plants - Nature of the checks to increase - Com- petition universal - Effects of Climate - Protection from the number of individuals - Complex relations of all animals and plants throughout nature - Struggle for life most ...
Página xvi
... animals tend to vary in some degree , and , secondly , that agri- culturists improve their domesticated animals by selec- tion ; and then , he adds , but what is done in this latter case " by art , seems to be done with equal efficacy ...
... animals tend to vary in some degree , and , secondly , that agri- culturists improve their domesticated animals by selec- tion ; and then , he adds , but what is done in this latter case " by art , seems to be done with equal efficacy ...
Página xxiv
... animals are not separated from the extinct by new creations , but are to be regarded as their descendants through contin- ued reproduction . " A well - known French botanist , M. Lecoq , writes in 1854 ( Etudes sur Géograph . Bot ...
... animals are not separated from the extinct by new creations , but are to be regarded as their descendants through contin- ued reproduction . " A well - known French botanist , M. Lecoq , writes in 1854 ( Etudes sur Géograph . Bot ...
Página 5
... animal and vegetable kingdoms . As many more individuals of each species are born than can possibly survive ; and as ... animals ; thirdly , Hybrid- ism , or the infertility of species and the fertility of varieties when intercrossed ...
... animal and vegetable kingdoms . As many more individuals of each species are born than can possibly survive ; and as ... animals ; thirdly , Hybrid- ism , or the infertility of species and the fertility of varieties when intercrossed ...
Página 7
... animals which have been cultivated , and which have varied during all ages under the most different climates and treatment , we are driven to conclude that this great variability is due to our domestic productions having been raised ...
... animals which have been cultivated , and which have varied during all ages under the most different climates and treatment , we are driven to conclude that this great variability is due to our domestic productions having been raised ...
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