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On the Origin of Species by Means of Natural Selection: Or, The Preservation ...
Vista completa - 1864
adapted affinities allied species America analogous ancient animals appear archipelago become bees believe birds breeds cause cells characters cirripedes climate closely allied colour common continuous crossed crustaceans degree difficulty distinct species divergence domestic doubt Edition eggs embryo existing exterminated extinct extremely facts favourable Fcap females fertilised fertility flowers formation forms fossil genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hermaphrodites hybrids important individuals inhabitants inherited insects instance instincts intercrossing intermediate larvae less living male mammals manner migration modification modified descendants natural selection naturalists nearly nest offspring organic organisation parent perfect pigeons pistil plants pollen Post present principle probably produced progenitor racters ranked reciprocal crosses remarked resemble rudimentary seeds sexual selection Silurian slight South America stamens sterility structure struggle successive supposed tend tion variability variations varieties vary Vols whole widely Woodcuts
Página 237 - If it could be proved that any part of the structure of any one species had been formed for the exclusive good of another species, it would annihilate my theory, for such could not have been produced through natural selection.
Página xxi - ... 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 coadaptation which justly excites our admiration.
Página 87 - Several writers have misapprehended or objected to the term Natural Selection. Some have even imagined that natural selection induces variability, whereas it implies only the preservation of such variations as arise and are beneficial to the being under its conditions of life.
Página 216 - 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.
Página 152 - The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was...
Página 70 - Hence, as more individuals are produced than can possibly survive, there must in every case be a struggle for existence, either one individual with another of the same species, or with the individuals of ^distinct species, or with the physical conditions of life. It is the doctrine of Malthus applied with manifold force to the whole animal and vegetable kingdoms; for in this case there can be no artificial increase of food, and no prudential restraint from marriage.
Página 603 - History of Rome. From the Earliest Times to the Establishment of the Empire. With the History of Literature and Art.
Página 79 - Battle within battle must be continually recurring with varying success; and yet in the...
Página 420 - Every species has come into existence coincident both in space and time with a pre-existing closely allied species.