On the Origin of Species by Means of Natural Selection: Or The Preservation of Favoured Races in the Struggle for LifeHumphrey Milford, Oxford University Press, 1923 - 454 páginas |
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Página 7
... animals , one of the first points which strikes us is , that they generally differ more from each other than do the individuals of any one species or variety in a state of nature . When we reflect on the vast diversity of the plants and ...
... animals , one of the first points which strikes us is , that they generally differ more from each other than do the individuals of any one species or variety in a state of nature . When we reflect on the vast diversity of the plants and ...
Página 8
... animal , and few things more difficult than to get it to breed freely under confinement , even in the many cases when the male and female unite . How many animals there are which will not breed , though living long under not very close ...
... animal , and few things more difficult than to get it to breed freely under confinement , even in the many cases when the male and female unite . How many animals there are which will not breed , though living long under not very close ...
Página 9
... animals and plants , though often weak and sickly , yet breeding quite freely under confinement ; and when , on the other hand , we see individuals , though taken young from a state of nature , perfectly tamed , long - lived , and ...
... animals and plants , though often weak and sickly , yet breeding quite freely under confinement ; and when , on the other hand , we see individuals , though taken young from a state of nature , perfectly tamed , long - lived , and ...
Página 10
... animals such agencies have produced very little direct effect , though apparently more in the case of plants . Under this point of view , Mr. Buckman's recent experiments on plants are extremely valuable . When all or nearly all the ...
... animals such agencies have produced very little direct effect , though apparently more in the case of plants . Under this point of view , Mr. Buckman's recent experiments on plants are extremely valuable . When all or nearly all the ...
Página 11
... animal can be named which has not in some country drooping ears ; and the view suggested by some authors , that the drooping is due to the disuse of the muscles of the ear , from the animals not being much alarmed by danger , seems ...
... animal can be named which has not in some country drooping ears ; and the view suggested by some authors , that the drooping is due to the disuse of the muscles of the ear , from the animals not being much alarmed by danger , seems ...
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Términos y frases comunes
accumulated adapted affinities allied species America amount analogous ancient appear Archipelago become bees believe birds breeds cause cells characters cirripedes climate closely allied colour common parent continuous crossed crustaceans degree difficulty distinct species divergence doubt embryo endemic Europe existing exterminated extinct extremely facts favourable fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hermaphrodites hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing land larvæ less living male mammals manner Marsupials migration modification modified descendants natural selection naturalists nearly nest oceanic islands offspring organisation perfect pigeons pistil plants pollen present principle probably produced progenitor ranked reciprocal crosses remarked resemble rock-pigeon rudimentary organs seeds sexual selection Silurian slight South America sterility structure struggle successive suppose swimbladder tend theory tion trees variability variation vary whole widely