The Foundations of the Origin of Species. Darwin Charles

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Note in the original, “Would it be more striking if we took animals, take Rhinoceros, and study their habitats?”

Note by Mr A. R. Wallace. “The want of similarity referred to, is, between the mountains of Brazil and Guiana and those of the Andes. Also those of the Indian peninsula as compared with the Himalayas. In both cases there is continuous intervening land.

“The islands referred to were, no doubt, the Galapagos for dissimilarity from S. America; our own Islands as compared with Europe, and perhaps Java, for similarity with continental Asia.”

The arguments against multiple centres of creation are given in the Origin, Ed. i. p. 352, vi. p. 499.

In the Origin, Ed. i. p. 366, vi. p. 516, the author does not give his views on the distribution of alpine plants as original but refers to Edward Forbes’ work (Geolog. Survey Memoirs, 1846). In his autobiography, Darwin refers to this. “I was forestalled” he says, “in only one important point, which my vanity has always made me regret.” (Life and Letters, i. p. 88.)

«The following is written on the back of a page of the MS.» Discuss one or more centres of creation: allude strongly to facilities of dispersal and amount of geological change: allude to mountain-summits afterwards to be referred to. The distribution varies, as everyone knows, according to adaptation, explain going from N. to S. how we come to fresh groups of species in the same general region, but besides this we find difference, according to greatness of barriers, in greater proportion than can be well accounted for by adaptation. «On representive species see Origin, Ed. i. p. 349, vi. p. 496.» This very striking when we think of cattle of Pampas, plants «?» &c. &c. Then go into discussion; this holds with 3 or 4 main divisions as well as the endless minor ones in each of these 4 great ones: in these I chiefly refer to mammalia &c. &c. The similarity of type, but not in species, in same continent has been much less insisted on than the dissimilarity of different great regions generically: it is more striking.

«I have here omitted an incomprehensible sentence.» Galapagos Islands, Tristan d’Acunha, volcanic islands covered with craters we know lately did not support any organisms. How unlike these islands in nature to neighbouring lands. These facts perhaps more striking than almost any others. [Geology apt to affect geography therefore we ought to expect to find the above.] Geological-geographical distribution. In looking to past times we find Australia equally distinct. S. America was distinct, though with more forms in common. N. America its nearest neighbour more in common, – in some respects more, in some less allied to Europe. Europe we find «?» equally European. For Europe is now part of Asia though not «illegible». Africa unknown, – examples, Elephant, Rhinoceros, Hippopotamus, Hyaena. As geology destroys geography we cannot be surprised in going far back we find Marsupials and Edentata in Europe: but geology destroys geography.

Rincon in Spanish means a nook or corner, it is here probably used to mean a small farm.

The following is written across the page: “No one would expect a set of similar varieties to be produced in the different countries, so species different.”

«The following passage seems to have been meant to follow here.» The parent of an organism, we may generally suppose to be in less favourable condition than the selected offspring and therefore generally in fewer numbers. (This is not borne out by horticulture, mere hypothesis; as an organism in favourable conditions might by selection be adapted to still more favourable conditions.)

Barrier would further act in preventing species formed in one part migrating to another part.

«The following notes occur on the back of the page.» Number of species not related to capabilities of the country: furthermore not always those best adapted, perhaps explained by creationists by changes and progress. «See p. 34, note 1.»

Although creationists can, by help of geology, explain much, how can he explain the marked relation of past and present in same area, the varying relation in other cases, between past and present, the relation of different parts of same great area. If island, to adjoining continent, if quite different, on mountain summits, – the number of individuals not being related to capabilities, or how &c. – our theory, I believe, can throw much light and all facts accord.

See Origin, Ed. i. p. 390, vi. p. 543.

On oscillation see Origin, Ed. i. p. 291, vi. p. 426.

«From the back of MS.» Effect of climate on stationary island and on continent, but continent once island. Moreover repeated oscillations fresh diffusion when non-united, then isolation, when rising again immigration prevented, new habitats formed, new species, when united free immigration, hence uniform characters. Hence more forms «on?» the island. Mountain summits. Why not true species. First let us recall in Part I, conditions of variation: change of conditions during several generations, and if frequently altered so much better [perhaps excess of food]. Secondly, continued selection [while in wild state]. Thirdly, isolation in all or nearly all, – as well to recall advantages of.

[In continent, if we look to terrestrial animal, long continued change might go on, which would only cause change in numerical number «? proportions»: if continued long enough might ultimately affect all, though to most continents «there is» chance of immigration. Some few of whole body of species must be long affected and entire selection working same way. But here isolation absent, without barrier, cut off such «illegible». We can see advantage 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 Origin, Ed. i. p. 390.» Moreover as the island continued changing, – continued slow changes, river, marshes, lakes, mountains &c. &c., new races as successively formed and a fresh occasional visitant.

If island formed continent, some species would emerge and immigrate. Everyone admits continents. We can see why Galapagos and C. Verde differ «see Origin, Ed. i. p. 398»], depressed and raised. We can see from this repeated action and the time required for a continent, why many more forms than in New Zealand «see Origin, Ed. i. p. 389 for a comparison between New Zealand and the Cape» no mammals or other classes «see however, Origin, Ed. i. p. 393 for the case of the frog». We can at once see how it comes when there has been an old channel of migration, – Cordilleras; we can see why Indian Asiatic Flora, – [why species] having a wide range gives better chance of some arriving at new points and being selected, and adapted to new ends. I need hardly remark no necessity for change.

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 Origin, Ed. i. pp. 339 and 349».

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 Origin, Ed. i. p. 292». This observation may be extended, that in all cases, subsiding land must be, in early stages, less favourable to formation of new species; but it will isolate them, and then if land recommences rising how favourable. As preoccupation is bar to diffusion to species, so would it be to a selected variety. But it would not be if that variety was better fitted to some not fully occupied station; so during elevation or the formation of new stations, is scene for new species. But during elevation not favourable to preservation of fossil (except in caverns «?»); when subsidence highly favourable in early stages to preservation of fossils; when subsidence, less sediment. So that our strata, as general rule will be the tomb of old species (not undergoing any change) when rising land the nursery. But if there be vestige will generally be preserved to future ages, the new ones will not be entombed till fresh subsidence supervenes. In this long gap we shall have no record: so that wonderful if we should get transitional forms. I do not mean every stage, for we cannot expect that, as before shown, until geologists will be prepared to say that although under unnaturally favourable condition we can trace in future ages short-horn and Herefordshire «see note 2, p. 26».

After “organs” is inserted, apparently as an afterthought: – “no, and instance metamorphosis, afterwards explicable.”

For analogical resemblances see Origin, Ed. i. p. 427, vi. p. 582.

“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,” Origin, Ed. i. p. 417, vi. p. 573.

“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,” Origin, Ed. i. p. 423, vi. p. 579.

The whole of this passage is obscure, but the text is quite clear, except for one illegible word.