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
... increase , will be treated of . This is the doctrine of Malthus , applied to the whole animal and vegetable kingdoms . As many more individuals of each species are born than can possibly survive ; and as , consequently , there is a ...
... increase , will be treated of . This is the doctrine of Malthus , applied to the whole animal and vegetable kingdoms . As many more individuals of each species are born than can possibly survive ; and as , consequently , there is a ...
Página 10
... increased size from amount of food , colour from par- ticular kinds of food or from light , and perhaps the thickness of fur from climate . Habit also has a decided influence , as in the period of flowering with plants when transported ...
... increased size from amount of food , colour from par- ticular kinds of food or from light , and perhaps the thickness of fur from climate . Habit also has a decided influence , as in the period of flowering with plants when transported ...
Página 30
... increasing size of the common gooseberry may be quoted . We see an astonishing improvement in many florists ' flowers , when the flowers of the present day are compared with drawings made only twenty or thirty years ago . When a race of ...
... increasing size of the common gooseberry may be quoted . We see an astonishing improvement in many florists ' flowers , when the flowers of the present day are compared with drawings made only twenty or thirty years ago . When a race of ...
Página 33
... increased in weight and in early maturity , compared with the stock formerly kept in this country . By comparing the accounts given in old pigeon treatises of carriers and tumblers with these breeds as now existing in Britain , India ...
... increased in weight and in early maturity , compared with the stock formerly kept in this country . By comparing the accounts given in old pigeon treatises of carriers and tumblers with these breeds as now existing in Britain , India ...
Página 34
... increased size and beauty which we now see in the varieties of the heartsease , rose , pelargonium , dahlia , and other plants , when compared with the older varieties or with their parent - stocks . No one would ever expect to get a ...
... increased size and beauty which we now see in the varieties of the heartsease , rose , pelargonium , dahlia , and other plants , when compared with the older varieties or with their parent - stocks . No one would ever expect to get a ...
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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