Charles Darwin's Works: The origin of species by means of natural selection...with additions and corrections from 6th and last English edD. Appleton, 1896 |
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Стр. 5
... less improved forms of life , and leads to what I have called Diver- gence of Character . In the next chapter I shall discuss the complex and little known laws of variation . In the five succeeding chapters , the most apparent and ...
... less improved forms of life , and leads to what I have called Diver- gence of Character . In the next chapter I shall discuss the complex and little known laws of variation . In the five succeeding chapters , the most apparent and ...
Стр. 6
... less do we know of the mutual relations of the innumerable inhabitants of the world during the many past geological epochs in its history . Although much remains obscure , and will long remain obscure , I can entertain no doubt , after ...
... less do we know of the mutual relations of the innumerable inhabitants of the world during the many past geological epochs in its history . Although much remains obscure , and will long remain obscure , I can entertain no doubt , after ...
Стр. 10
... less water at some particular period of growth , will determine whether or not a plant will produce seeds . I cannot here give the details which I have collected and elsewhere published on this curious subject ; but to show how singular ...
... less water at some particular period of growth , will determine whether or not a plant will produce seeds . I cannot here give the details which I have collected and elsewhere published on this curious subject ; but to show how singular ...
Стр. 12
... less and the bones of the leg more , in proportion to the whole skeleton , than do the same bones in the wild - duck ; and this change may be safely attributed to the domestic duck flying much less , and walking more , than its wild ...
... less and the bones of the leg more , in proportion to the whole skeleton , than do the same bones in the wild - duck ; and this change may be safely attributed to the domestic duck flying much less , and walking more , than its wild ...
Стр. 15
... less strange and commoner deviations may be freely admitted to be inheritable . Perhaps the correct way of viewing the whole subject would be , to look at the inheritance of every character whatever as the rule , and non - in- heritance ...
... less strange and commoner deviations may be freely admitted to be inheritable . Perhaps the correct way of viewing the whole subject would be , to look at the inheritance of every character whatever as the rule , and non - in- heritance ...
Часто встречающиеся слова и выражения
acquired adapted advantage allied analogous appear Asa Gray beak become bees believe birds breeds caudicle cause cells characters climate closely colour common correlated crossed cuckoo degree developed difficulty distinct species disuse domestic animals domestic races doubt effects eggs existence extinct extremely facts favourable females flowers forms Fritz Müller genera genus giraffe gradations greater number groups habits Hence hermaphrodites hive-bee important improved increase in number individual differences inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ large number larger genera larvæ less likewise males manner Melipona Mivart natural selection naturalists nearly nest occasionally offspring organisation organs origin Origin of Species parent perfect period pigeons pollen pollen-grains present preserved principle probably produced progenitor quadrupeds rank Red Grouse relation remarked resemble rock-pigeon seeds sexes sexual sexual selection slight stamens sterile structure struggle supposed swimbladder tend tendency tion transitional tree variability variations varieties vary widely wings young
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Стр. 77 - We behold the face of nature bright with gladness, we often see superabundance of food ; we do not see or we forget, that the 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 of prey...
Стр. 109 - ... perform strange antics before the females, which, standing by as spectators, at last choose the most attractive partner. Those who have closely attended to birds in confinement well know that they often take individual preferences and dislikes; thus Sir R. Heron has described how a pied peacock was eminently attractive to all his hen birds.
Стр. 229 - If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.
Стр. 1 - These facts seemed to me to throw some light on the origin of species — that mystery of mysteries, as it has been called by one of our greatest philosophers.
Стр. 162 - ... of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups. Of the many twigs which flourished when the tree was a mere bush, only two or three, now grown into great branches, yet survive and bear the other branches ; so with the species which lived during long-past geological periods, very few have left living and modified descendants.
Стр. 203 - Our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign any reason why this or that part differs, more or less, from the same part in the parents.
Стр. 77 - I have called this principle, by which each slight variation, if useful, is preserved, by the term natural selection, in order to mark its relation to man's power of selection. But the expression often used by Mr. Herbert Spencer, of the Survival of the Fittest, is more accurate, and is sometimes equally convenient.
Стр. 163 - From the first growth of the tree, many a limb and branch has decayed and dropped off; and these lost branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only from having been found in a fossil state.
Стр. 244 - Why should not Nature take a sudden leap from structure to structure? On the theory of natural selection, we can clearly understand why she should not; for natural selection acts only by taking advantage of slight successive variations; she can never take a great and sudden leap, but must advance by short and sure, though slow steps.
Стр. 138 - The truth of the principle, that the greatest amount of life can be supported by great diversification of structure^ is seen under many natural circumstances. In an extremely small area, especially if freely open to immigration, and where the contest between individual and individual must be severe, we always find great diversity in its inhabitants. For instance, I found that a piece of turf, three feet by four in size, which had been...