It must be particularly pointed out that in Mr. Distant's general discussion of the subject he has most clearly suggested that the present day colouring, which is classed by him as assimilative (in opposition to adaptive) was only developed in the earliest geological epochs, and prior to the first appearance of natural selection as an efficient factor—according to his conception of that first appearance. Fortunately we are able to obtain, from certain passages, some idea as to this conception, for with regard to the Lias formation of the Jurassic Period (Mesozoic), when the gigantic Enaliosaurians abounded, it is freely admitted that "Here we see natural selection, with its iron and implacable rule, a real factor";[1] and, further, in the later essays on "Mimicry," good cause is shown for the recognition of the occurrence of natural selection so far back as the Carboniferous Period in Palæozoic times.
But when we come to consider the examples adduced in support of the above suggestion, we at once find that the fundamental proposition is practically disregarded. A single instance will suffice. Referring to the colouring of primitive man, it is remarked that: "Their colour would have been uniform, either derived from their more brutish ancestors, or, possibly, a more assimilative colouration may have ensued to the soil on which they walked."[2] It will be thus seen that the vast majority of
- ↑ This quotation with its context is as follows:—"Thus, after a period of animal evolution which may be computed by millions of years, and in which fish abounded, perhaps not yet altogether under a severe stress of selection and survival, the Mesozoic period arrives, when, in the words of Oscar Schmidt, 'the Placoids and Ganoids, hitherto predominating in the ocean almost without a foe, now found overwhelming enemies in the true Sea-lizards or Enaliosaurians, especially the Ichthyosaura and Plesiosauria.' Here we see natural selection, with its iron and implacable rule, a real factor in the lives and development of these creatures, connected and increasing with an advancing animal evolution, but still only a term to express the modifying influences incidental to a struggle for existence" (pp. 388–9).—Ed.
- ↑ Quotations are best unabridged. The following is as printed:—"As De Quatrefages has remarked, 'The first men who peopled the centre of human appearance must at first have differed from each other only in individual features.' Their colour would have been uniform, either derived from their more brutish ancestors, or possibly, as their habits became less arboreal, a more assimilative colouration may have ensued to the soil on which they walked" (p. 403).—Ed.
A previous paragraph, not quoted, reads: "But although facts may be found to support new suggestions, such as a possible original assimilative colouration of man, the quest for such produces other recorded observations, which, though not altogether contradictory to the view, still point to other causes, support other conclusions, and reassert the problem we seek to solve" (p. 400).— Ed.
