On the Origin of Species: By Means of Natural Selection, Or, the Preservation of Favored Races in the Struggle for LifeAppleton, 1883 - Всего страниц: 458 |
Результаты поиска по книге
Результаты 1 – 5 из 64
Стр. 12
... kind truly , were the offspring of any single species , then such facts would have great weight in making us doubt about the immutability of the many closely allied natural species - for nstance , of the many foxes - inhabiting ...
... kind truly , were the offspring of any single species , then such facts would have great weight in making us doubt about the immutability of the many closely allied natural species - for nstance , of the many foxes - inhabiting ...
Стр. 24
... kind of selection is , in fact , likewise followed ; for hardly any one is so careless as to breed from his worst animals . In regard to plants , there is another means of observing the accumulated effects of selection - namely , by ...
... kind of selection is , in fact , likewise followed ; for hardly any one is so careless as to breed from his worst animals . In regard to plants , there is another means of observing the accumulated effects of selection - namely , by ...
Стр. 25
... kind in the country . But , for our pur- pose , a form of Selection , which may be called Unconscious , and which results from every one trying to possess and breed from the best individual animals , is more important . Thus , a man who ...
... kind in the country . But , for our pur- pose , a form of Selection , which may be called Unconscious , and which results from every one trying to possess and breed from the best individual animals , is more important . Thus , a man who ...
Стр. 26
... kind of unconscious selection going on . We see he value set on animals even by the barbarians of Tierra del Fuego , by their killing and devouring their old women , in times of dearth , as of less value than their dogs . In plants the ...
... kind of unconscious selection going on . We see he value set on animals even by the barbarians of Tierra del Fuego , by their killing and devouring their old women , in times of dearth , as of less value than their dogs . In plants the ...
Стр. 34
... kind ever do appear in a state of nature and are capable of reproduction ( which is not always the case ) , as they occur rarely and singly , their preservation would depend on unusually favourable circumstances . They would , also ...
... kind ever do appear in a state of nature and are capable of reproduction ( which is not always the case ) , as they occur rarely and singly , their preservation would depend on unusually favourable circumstances . They would , also ...
Другие издания - Просмотреть все
Часто встречающиеся слова и выражения
adapted admit affinities allied species America analogous ancient appear Asa Gray beak become bees believe belonging birds breeds cause cells characters climate closely allied colour continued crossed crustaceans degree developed difficulty distinct species doubt effects eggs embryo existing extinct extremely facts favourable fertilised fertility flowers formations 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 male mammals manner Marsupials migration modified descendants natural selection naturalists nearly nest occasionally occur oceanic islands offspring organisation organs parent peculiar perfect pigeon pistil pollen present preserved principle probably produced quadrupeds ranked reciprocal crosses remarked resemblance rudimentary seeds sexual selection slight South America stamens sterility structure struggle successive supposed theory tion variability variations varieties vary whilst whole wings young
Популярные отрывки
Стр. 65 - It may be said that natural selection is daily and hourly scrutinising, throughout the world, every variation, even the slightest; rejecting that which is bad, preserving and adding up all that is good; silently and insensibly working, whenever and wherever opportunity offers, at the improvement of each organic being in relation to its organic and inorganic conditions of life.
Стр. 104 - The green and budding twigs may represent existing species, and those produced during former years may represent the long succession of extinct species. At each period of growth all the growing twigs have tried to branch out on all sides, and to overtop and kill the surrounding twigs and branches, in the same manner as species and groups of species have at all times overmastered other species in the great battle for life.
Стр. 57 - Newman, who has long attended to the habits of humble-bees believes that 'more than two-thirds of them are thus destroyed all over England'.
Стр. 23 - ... that which enables the agriculturist not only to modify the character of his flock, but to change it altogether. It is the magician's wand, by means of which he may summon into life whatever form and mould he pleases.
Стр. 146 - 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. 50 - But a plant on the edge of a desert is said to struggle for life against the drought, though more properly it should be said to be dependent on the moisture.
Стр. 429 - These laws, taken in the largest sense, being Growth with reproduction; Inheritance which is almost implied by reproduction; Variability from the indirect and direct action of the conditions of life, and from use and disuse...
Стр. 104 - The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was young, budding twigs; and this connection 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.
Стр. 425 - Nevertheless all living things have much in common, in their chemical composition, their cellular structure, their laws of growth, and their liability to injurious influences.
Стр. 2 - ... species had not been independently created, but had descended, like varieties, from other species. Nevertheless, such a conclusion, even if well founded, would be unsatisfactory, until it could be shown how the innumerable species inhabiting this world have been modified so as to acquire that perfection of structure and co-adaptation which justly excites our admiration.