adapted to their new and varying conditions as they were in their native country and habitat, we cannot believe that every place or office in the economy of the island would be as well filled as on a continent where the number of aboriginal species is far greater and where they consequently hold a more strictly limited place. We might therefore expect on our island that although very many slight variations were of no use to the plastic individuals, yet that occasionally in the course of a century an individual might be born{406} of which the structure or constitution in some slight degree would allow it better to fill up some office in the insular economy and to struggle against other species. If such were the case the individual and its offspring would have a better _chance_ of surviving and of beating out its parent form; and if (as is probable) it and its offspring crossed with the unvaried parent form, yet the number of the individuals being not very great, there would be a chance of the new and more serviceable form being nevertheless in some slight degree preserved. The struggle for existence would go on annually selecting such individuals until a new race or species was formed. Either few or all the first visitants to the island might become modified, according as the physical conditions of the island and those resulting from the kind and number of other transported species were different from those of the parent country--according to the difficulties offered to fresh immigration--and according to the length of time since the first inhabitants were introduced. It is obvious that whatever was the country, generally the nearest from which the first tenants were transported, they would show an affinity, even if all had become modified, to the natives of that country and even if the inhabitants of the same source (?) had been modified. On this view we can at once understand the cause and meaning of the affinity of the fauna and flora of the Galapagos Islands with that of the coast of S. America; and consequently why the inhabitants of these islands show not the smallest affinity with those inhabiting other volcanic islands, with a very similar climate and soil, near the coast of Africa{407}. {402} This brief discussion is represented in the _Origin_, Ed. i. by a much fuller one (pp. 356, 383, vi. pp. 504, 535). See, however, the section in the present Essay, p. 168. {403} On the formation of new stations, see _Origin_, Ed. i. p. 292, vi. p. 429. {404} _Origin_, Ed. i. pp. 390, 400, vi. pp. 543, 554. {405} In the MS. _some of the species ... nourishing quality_ is doubtfully erased. It seems clear that he doubted whether such a problematical supply of food would be likely to cause variation. {406} At this time the author clearly put more faith in the importance of sport-like variation than in later years. {407} _Origin_, Ed. i. p. 398, vi. p. 553.