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 4
... shall then see how Natural Selection almost in- evitably causes much Extinction of the less improved forms of life , and leads to what I have called Divergence of Character . In the next chapter I shall discuss 4 ON THE ORIGIN OF SPECIES.
... shall then see how Natural Selection almost in- evitably causes much Extinction of the less improved forms of life , and leads to what I have called Divergence of Character . In the next chapter I shall discuss 4 ON THE ORIGIN OF SPECIES.
Página 8
... less water at some particular period of growth , will determine whether or not the plant sets a seed . I cannot here enter on the copious details which I have collected on this curious subject ; but to show how singular the laws are ...
... less water at some particular period of growth , will determine whether or not the plant sets a seed . I cannot here enter on the copious details which I have collected on this curious subject ; but to show how singular the laws are ...
Página 10
... less and the bones of the leg more , in proportion to the whole skeleton , than do the same bones in the wild - duck ; and I presume that this change may be safely attributed to the domestic duck flying much less , and walking more ...
... less and the bones of the leg more , in proportion to the whole skeleton , than do the same bones in the wild - duck ; and I presume that this change may be safely attributed to the domestic duck flying much less , and walking more ...
Página 15
... less uni- formity of character than in true species . Domestic races of the same species , also , often have a somewhat monstrous character ; by which I mean , that , although differing from each other , and from other species of the ...
... less uni- formity of character than in true species . Domestic races of the same species , also , often have a somewhat monstrous character ; by which I mean , that , although differing from each other , and from other species of the ...
Página 20
... less distinct breeds might be specified . The In the skeletons of the several breeds , the develop- ment of the bones of the face in length and breadth and curvature differs enormously . The shape , as well as the breadth and length of ...
... less distinct breeds might be specified . The In the skeletons of the several breeds , the develop- ment of the bones of the face in length and breadth and curvature differs enormously . The shape , as well as the breadth and length of ...
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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