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action adapted advantage allied America amount ancient animals appear become believe birds breeds cause chapter characters climate closely common compared considered continuous crossed descended developed difficulty distinct domestic doubt effects existing explained extinct extremely facts families favourable fertility flowers follow formations forms genera genus geological give given greater groups habits hand Hence hybrids important improved increase individuals inhabitants inherited insects instance instincts intermediate islands kinds known land laws less lines living look male manner means modification namely natural selection naturalists nearly never occur offspring organic origin parent perfect period plants points present principle probably produced range ranked reason remarked seeds seems seen separated single slight sometimes species sterility structure struggle successive suppose tend theory tion variability variation varieties vary whole widely
Síđa 423 - It is interesting to contemplate a tangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other and dependent upon each other in so complex a manner, have all been produced by laws acting around us.
Síđa 422 - In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history.
Síđa 423 - Variability from the indirect and direct action of the conditions of life, and from use and disuse; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less-improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of higher animals, directly follows.
Síđa 9 - On my return home, it occurred to me, in 1837, that something might perhaps be made out on this question by patiently accumulating and reflecting on all sorts of facts which could possibly have any bearing on it. After five years' work I allowed myself to speculate on the subject, and drew up some short notes ; these I enlarged in 1844 into a sketch of the conclusions which then seemed to me probable : from that period to the present day I have steadily pursued the same object. I hope that I may...
Síđa 423 - There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.
Síđa 61 - 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.
Síđa 72 - Near villages and small towns I have found the nests of humble-bees more numerous than elsewhere, which I attribute to the number of cats that destroy the mice.
Síđa 169 - 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.
Síđa 420 - Our classifications will come to be, as far as they can be so made, genealogies ; and will then truly give what may be called the plan of creation.
Síđa 11 - ... 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 most justly excites our admiration.