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 3
... plant itself . The author of the Vestiges of Creation would , I presume , say that , after a certain unknown number of generations , some bird had ... plants would offer the best chance of making out this obscure problem . Nor INTRODUCTION.
... plant itself . The author of the Vestiges of Creation would , I presume , say that , after a certain unknown number of generations , some bird had ... plants would offer the best chance of making out this obscure problem . Nor INTRODUCTION.
Página 7
... 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 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 ...
Página 8
... plants , such as wheat , still often yield new varieties : our oldest domesticated animals are still capable of rapid improvement or modification . It has been disputed at what period of life the causes of variability , whatever they ...
... plants , such as wheat , still often yield new varieties : our oldest domesticated animals are still capable of rapid improvement or modification . It has been disputed at what period of life the causes of variability , whatever they ...
Página 9
... plants have pollen utterly worthless , in the same exact condition as in the most sterile hybrids . When , on the one hand , we see domesticated animals and plants , though often weak and sickly , yet breeding quite freely under ...
... plants have pollen utterly worthless , in the same exact condition as in the most sterile hybrids . When , on the one hand , we see domesticated animals and plants , though often weak and sickly , yet breeding quite freely under ...
Página 10
... plants . Under this point of view , Mr. Buckman's recent experiments on plants are extremely valuable . When all or nearly all the individuals exposed to certain conditions are affected in the same way , the change at first appears to ...
... plants . Under this point of view , Mr. Buckman's recent experiments on plants are extremely valuable . When all or nearly all the individuals exposed to certain conditions are affected in the same way , the change at first appears to ...
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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