. The wonder of life . ensure that the insect-visitors are dusted withpollen, and thus to secure cross-fertihzation; the peacockis adapted to captivate the pea-hen ; the mother mammalis adapted for the prolonged pre-natal Hfe of the young;the so-called egg-tooth at the end of a young birds billis adapted to the single operation of breaking the egg-shell—and so on throughout the whole of the animate world. Itis indeed a mistake to dwell upon signal instances of adapta-tions, since (apart from degenerative changes in old age,morbid processes, perverted instincts, rudimentary orvestigial structur
. The wonder of life . ensure that the insect-visitors are dusted withpollen, and thus to secure cross-fertihzation; the peacockis adapted to captivate the pea-hen ; the mother mammalis adapted for the prolonged pre-natal Hfe of the young;the so-called egg-tooth at the end of a young birds billis adapted to the single operation of breaking the egg-shell—and so on throughout the whole of the animate world. Itis indeed a mistake to dwell upon signal instances of adapta-tions, since (apart from degenerative changes in old age,morbid processes, perverted instincts, rudimentary orvestigial structures, and certain indifferent characterswhich are not known to have any vital significance) ahnostevery detail of structure and function may be regarded asadaptive. The Mole.—In illustration of adaptive characters letus consider a common animal like the mole, the little Fig| 81 .TT-Leaf-insedts^ (Phyllium) Froi^a specimen. A, tfeefgreenform on gre^i leaves; B, the browrijorrri 6n brov^^Ti^ses ;Wnd C, the young THE WONDER OF LIFE 519 gentleman in the velvet coat, who long ago discoveredthe possibility of a subterranean hfe for a warm-bloodedanimal, and disturbed the earthworms in the retreatswhere they had for so long enjoyed relative a bundle of adaptations the creature is ! The out-turned hand has become a powerful shovel, aided by thepresence of an extra bone, the sickle, to the inner side^of thethumb ; the shoulder-girdle is very strong and the pectoralmuscles are those of an athlete ; the long muscular sensitivesnout, which probes the way, is strengthened by a specialbone near the tip ; the hind legs remain purely locomotor ;the absence of the external trumpet of the ear is an adapta-tion to the reduction of friction; the minute eyes are wellhidden among the hair and thus saved from being rubbed ;and there must be some special advantage too in the waythe hairs stand out vertically hke the pile on velvet. Theeye is not well finished, as an instrument-
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Keywords: ., bookcentury1900, booksubjectnaturalhistory, booksubjectzoology
