Page:The Zoologist, 4th series, vol 2 (1898).djvu/497

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ASSIMILATIVE COLOURATION.
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assimilative colouration, it seems even more opposed to evolu- tionary ideas to predicate that because a mammal, as we know it at the present time, has a striped coat, it had also the same appearance in past geological epochs. Yet this seems to have been the method of Prof. Heilprin, who has written so excellently on the distribution of animals, considered geologically as well as geographically. Thus we read:—"The striped Hyena may be traced back to the older (Pliocene) H. arvennensis of Central France, and the brown form not improbably to the Miocene (or Pliocene) H. exima of Pikermi, Greece."[1] At the present day we have brown, spotted, and striped Hyenas (H. brunnea, H. crocuta, and H. striata) all found in, though not confined to, the continent of Africa, and however they may differ osteologically, and however distinctly these differences may be detected in fossil forms, yet surely we are not warranted in concluding that identity of colouration has survived from the geological past. But speculating on the generally accepted conclusion that spots and stripes succeeded a uniform or concolorous decoration, and re- membering that the three forms of markings referred to can almost be found at the present time, it seems we ought to be very cautious, as evolutionists, in concluding that the Hyena had developed either spots, or stripes, in Miocene or Pliocene times. Remembering the numerous remains of the genus found in the Pleistocene deposits of Europe, and that, as Prof. Heilprin remarks, it was from these north temperate regions "the Ethio- pian realm has drawn much of its existing distinctive fauna," and that the widely distributed Cave Hyena (H. spelæa), if not identical with the present spotted form (H. crocuta), was "without doubt its direct ancestor," it remains a suggestion as to what the original colouration was, altogether apart from structural specific distinction. Among the fossils of Pikermi, Gaudry found the successive stages by which the ancient Civets passed into the more modern Hyenas.[2]

  1. 'Geograph. and Geolog. Distrib. Animals,' p. 386. Prof. Boyd Dawkins likewise includes the "Spotted Hyena" (H. spelæa) in his list of mammalia occurring in Great Britain in association with Palaeolithic implements in the Pleistocene river deposits and the caves" ('Journ. Anthrop. Instit.,' vol. xviii. p. 243).
  2. Huxley, 'Collected Essays,' vol. ii. p. 241.