The Origin of Species by Means of Natural Selection: Or the Preservation of Favored Races in the Struggle for LifeD. Appleton, 1904 - 435 páginas |
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Página 32
... birds ; " and , continues the courtly his- torian , " His Majesty by crossing the breeds , which method was never practised before , has improved them astonishingly . " About this same period the Dutch were as eager about pigeons as ...
... birds ; " and , continues the courtly his- torian , " His Majesty by crossing the breeds , which method was never practised before , has improved them astonishingly . " About this same period the Dutch were as eager about pigeons as ...
Página 58
... birds and insects in North America and Europe , which differ very slightly from each other , have been ranked by one eminent naturalist as undoubted species , and by another as varieties , or , as they are often called geographical ...
... birds and insects in North America and Europe , which differ very slightly from each other , have been ranked by one eminent naturalist as undoubted species , and by another as varieties , or , as they are often called geographical ...
Página 59
... birds from the closely neighbouring islands of the Galapagos archipelago , one with another , and with those from the American mainland , I was much struck how entirely vague and arbitrary is the dis- tinction between species and ...
... birds from the closely neighbouring islands of the Galapagos archipelago , one with another , and with those from the American mainland , I was much struck how entirely vague and arbitrary is the dis- tinction between species and ...
Página 77
... birds which are idly singing round us mostly live on insects or seeds , and are thus constantly destroying life ; or we forget how largely these songsters , or their eggs , or their nestlings , are destroyed by birds and beasts . Į of ...
... birds which are idly singing round us mostly live on insects or seeds , and are thus constantly destroying life ; or we forget how largely these songsters , or their eggs , or their nestlings , are destroyed by birds and beasts . Į of ...
Página 78
... birds , its existence depends on them ; and it may metaphorically be said to struggle with other fruit - bearing plants , in tempting the birds to devour and thus disseminate its seeds . In these several senses , which pass into each ...
... birds , its existence depends on them ; and it may metaphorically be said to struggle with other fruit - bearing plants , in tempting the birds to devour and thus disseminate its seeds . In these several senses , which pass into each ...
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Términos y frases comunes
adapted affinities allied species America ancient appear Asa Gray beak become bees believe belonging birds breeds cause cells characters climate closely allied colour common continent crossed crustaceans degree developed difficulty distinct species domestic doubt effects eggs embryo existing extinct extremely facts favourable fertilised fertility flowers formation forms fossil Fritz Müller genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hybrids important individuals inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ larvæ less living males mammals manner marsupials migration modified descendants natural selection naturalists nearly nest occasionally offspring organisation organs parent peculiar perfect pigeon pistil pollen present principle probably produced progenitor quadrupeds ranked remarked resemblance rudimentary seeds sexual selection Silurian slight South America stamens sterility structure successive supposed swimbladder tend theory tion trees variability variations varieties vary whilst whole wings young