The Foundations of the Origin of Species. Darwin Charles
of isolation. But let us take case of island thrown up by volcanic agency at some distances, here we should have occasional visitants, only in few numbers and exposed to new conditions and «illegible» more important, – a quite new grouping of organic beings, which would open out new sources of subsistence, or «would» control «?» old ones. The number would be few, can old have the very best opportunity. «The conquest of the indigenes by introduced organisms shows that the indigenes were not perfectly adapted, see
If island formed continent, some species would emerge and immigrate. Everyone admits continents. We can see why Galapagos and C. Verde differ «see
Finally, as continent (most extinction «?» during formation of continent) is formed after repeated elevation and depression, and interchange of species we might foretell much extinction, and that the survivor would belong to same type, as the extinct, in same manner as different part of same continent, which were once separated by space as they are by time «see
As all mammals have descended from one stock, we ought to expect that every continent has been at some time connected, hence obliteration of present ranges. I do not mean that the fossil mammifers found in S. America are the lineal successors «ancestors» of the present forms of S. America: for it is highly improbable that more than one or two cases (who will say how many races after Plata bones) should be found. I believe this from numbers, who have lived, – mere «?» chance of fewness. Moreover in every case from very existence of genera and species only few at one time will leave progeny, under form of new species, to distant ages; and the more distant the ages the fewer the progenitors. An observation may be here appended, bad chance of preservation on rising island, the nurseries of new species, appeal to experience «see
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After “organs” is inserted, apparently as an afterthought: – “no, and instance metamorphosis, afterwards explicable.”
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For analogical resemblances see
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“Practically when naturalists are at work, they do not trouble themselves about the physiological value of the characters… If they find a character nearly uniform… they use it as one of high value,”
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“We are cautioned … not to class two varieties of the pine-apple together, merely because their fruit, though the most important part, happens to be nearly identical,”
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The whole of this passage is obscure, but the text is quite clear, except for one illegible word.
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«The exact position of the following passage is uncertain:» “just as it is not likely every present breed of fancy birds and cattle will propagate, only some of the best.”
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This suggests that the author was not far from the principle of divergence on which he afterwards laid so much stress. See
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That is to say the same conditions occurring in different parts of the globe.
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The position of the following is uncertain, “greyhound and racehorse have an analogy to each other.” The same comparison occurs in the
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Written between the lines occurs: – “extend to birds and other classes.”
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Written between the lines occurs: – “many bones merely represented.”
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In the
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The sentence is difficult to decipher.
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In the
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See
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The following passage seems to have been meant to precede the sentence beginning “These facts”: – “It is evident, that when in each individual species, organs are metamorph. a unity of type extends.”
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This is, I believe, the first place in which the author uses the words “theory of descent.”
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The sentence should probably run, “Let us take the case of the vertebrata: if we assume them to be descended from one parent, then by this theory they have been altered &c.”
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That is “we should call it a morphological fact.”
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In the
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See
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In the
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The following passages are written across the page: – “They pass through the same phases, but some, generally called the higher groups, are further metamorphosed.
? Degradation and complication? no tendency to perfection.
? Justly argued against Lamarck?”
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An almost identical passage occurs in the
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The following: “Deaths of brothers «when» old by same peculiar disease” which is written