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 15
... varieties when crossed , ―a subject hereafter to be discussed ) , domestic races of the same species differ from each other in the same manner as , only in most cases in a lesser degree than , do closely - allied species of the same ...
... varieties when crossed , ―a subject hereafter to be discussed ) , domestic races of the same species differ from each other in the same manner as , only in most cases in a lesser degree than , do closely - allied species of the same ...
Página 30
... varieties of the same species in the flower - garden ; the diversity of leaves , pods , or tubers , or whatever part is valued , in the kitchen - garden , in comparison with the flowers of the same varieties ; and the diversity of fruit ...
... varieties of the same species in the flower - garden ; the diversity of leaves , pods , or tubers , or whatever part is valued , in the kitchen - garden , in comparison with the flowers of the same varieties ; and the diversity of fruit ...
Página 34
... varieties , and whether or not two or more species or races have become blended together by crossing , may plainly be recognised in the increased size and beauty which we now see in the varieties of the heartsease , rose , pelargonium ...
... varieties , and whether or not two or more species or races have become blended together by crossing , may plainly be recognised in the increased size and beauty which we now see in the varieties of the heartsease , rose , pelargonium ...
Página 35
... varieties kept by savages have more of the character of species than the varieties kept in civilised countries . On the view here given of the all - important part which selection by man has played , it becomes at once obvious how it is ...
... varieties kept by savages have more of the character of species than the varieties kept in civilised countries . On the view here given of the all - important part which selection by man has played , it becomes at once obvious how it is ...
Página 38
... varieties . The keeping of a large number of individuals of a species in any country requires that the species should be placed under favourable conditions of life , so as to breed freely in that country . When the individuals of any ...
... varieties . The keeping of a large number of individuals of a species in any country requires that the species should be placed under favourable conditions of life , so as to breed freely in that country . When the individuals of any ...
Otras ediciones - Ver todas
On the Origin of Species by Means of Natural Selection: or the Preservation ... Charles Darwin Vista previa limitada - 2023 |
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