"Why does individual die? To perpetuate certain peculiarities (therefore adaptation), and obliterate accidental varieties, and to accommodate itself to change (for, of course, change, even in varieties, is accommodation).
Now this argument applies to species.
"If individual cannot propagate he has no issue--so with species.
"If SPECIES generate other SPECIES, their race is not utterly cut off:--like golden pippins, if produced by seed, go on--otherwise all die.
"The fossil horse generated, in South Africa, zebra--and continued--perished in America.
"All animals of same species are bound together just like buds of plants, which die at one time, though produced either sooner or later. Prove animals like plants--trace gradation between associated and non-associated animals--and the story will be complete."Here we have the view already alluded to of a term of life impressed on a species.
But in the following note we get extinction connected with unfavourable variation, and thus a hint is given of natural selection:
"With respect to extinction, we can easily see that [a] variety of [the] ostrich (Petise), may not be well adapted, and thus perish out; or, on the other hand, like Orpheus [a Galapagos bird], being favourable, many might be produced. This requires [the] principle that the permanent variations produced by confined breeding and changing circumstances are continued and produced according to the adaptation of such circumstance, and therefore that death of species is a consequence (contrary to what would appear from America) of non-adaptation of circumstances."The first part of the next extract has a similar bearing. The end of the passage is of much interest, as showing that he had at this early date visions of the far-reaching character of the theory of evolution:--"With belief of transmutation and geographical grouping, we are lead to endeavour to discover CAUSES of change; the manner of adaptation (wish of parents??), instinct and structure becomes full of speculation and lines of observation. View of generation being condensation (I imagine him to mean that each generation is "condensed" to a small number of the best organized individuals.) test of highest organisation intelligible...My theory would give zest to recent and fossil comparative anatomy; it would lead to the study of instincts, heredity, and mind-heredity, whole [of] metaphysics.
"It would lead to closest examination of hybridity and generation, causes of change in order to know what we have come from and to what we tend--to what circumstances favour crossing and what prevents it--this, and direct examination of direct passages of structure in species, might lead to laws of change, which would then be [the] main object of study, to guide our speculations."The following two extracts have a similar interest; the second is especially interesting, as it contains the germ of concluding sentence of the 'Origin of Species': ('Origin of Species' (1st edition), page 490:--"There is a grandeur in this view of life, with its several powers, having been originally breathed 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.")--"Before the attraction of gravity discovered it might have been said it was as great a difficulty to account for the movement of all [planets] by one law, as to account for each separate one; so to say that all mammalia were born from one stock, and since distributed by such means as we can recognise, may be thought to explain nothing.
"Astronomers might formerly have said that God fore-ordered each planet to move in its particular destiny. In the same manner God orders each animal created with certain forms in certain countries, but how much more simple and sublime [a] power--let attraction act according to certain law, such are inevitable consequences--let animals be created, then by the fixed laws of generation, such will be their successors.
