Page:The Zoologist, 4th series, vol 3 (1899).djvu/369

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BIOLOGICAL SUGGESTIONS.
MIMICRY.

By W.L. Distant.

(Continued from p. 315.)

In all reflections on the wonderful adaptations in nature by which living creatures obtain a protection from their enemies by assimilative colour or structure, we must remember that in the struggle for existence fecundity plays no small part in producing survival. As De Quincey spoke of man in China as being but a weed, so throughout nature we often find excessive reproduction alone preventing extermination, and quite replacing the aid of protective or mimetic disguise in the "survival of the fittest." It is no longer the protection of the few, but the superfluous number of the attacked that militates against annihilation. As Mr. Harting has observed:—"The enormous rate of increase in fish, as compared with the rate of increase in their natural enemies, will always result in there being enough to spare for man and Otter—ay, for Kingfisher and Heron too."[1] Weismann recognizes the same truth in the remark:—"No better arrangement for the maintenance of the species under such circumstances can be imagined than that supplied by diminishing the duration of life, and simultaneously increasing the rapidity of reproduction."[2] Take the Orthoptera as found on the Transvaal veld—where most of these pages were written—which not only during the summer season literally supply the almost sole avian banquet, but are doubtless the prey of other enemies as well; and, although the usual colouration of these insects is more or less approximate to the short grasses among which they live, no apparent protection is afforded thereby, and their great reproductive powers seem their only protection against extinction. The American Lobster is another case in point. Mr. F.H. Herrick, of the United States Fish Commission, who suggests that its habits are the same as that of the European representative, states that out of the 10,000 eggs produced at one time, not more than two arrive at maturity, and that even that estimate is probably too high, as the fisheries are

  1. 'Zoologist,' 3rd ser. vol. xviii. pp. 44–5
  2. 'Lectures on Heredity,' &c. Eng. Transl. 2nd edit. vol. i. p. 17