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Show 138 THE DESCENT OF 1\IAN. PART I. "tion could only have endowed the savage with a brain '' a little superior to that of an ape." Although the intellectual powers and social habits of man are of paramount importance to him, we must not underrate the importance of his bodily structure, to which subject the remainder of this chapter will be devoted. The development of the intellectual and social or moral faculties will be discussed in the following chapter. Even to hammer with precision is no easy matter, as every one who has tried to learn carpentry will admit. To throw a stone with as true an aim as can a Fuegian in defending himself, or in killing birds, requires the most consummate perfection in the correlated action of the muscles of the hand, arm, and shoulder, not to mention a fine sense of touch. In throwing a stone or spear, and in many other actions, a man must stand firmly on his feet ; and this again demands the perfect coadaptation of numerous muscles. To chip a flint into the rudest tool, or to form a barbed spear or hook from a bone, demands the use of a perfect hand ; for, as a most capable judge, Mr. Schoolcraft, 60 remarks, the shaping fragments of stone into knives, lances, or arrow-heads, shews " extra" ordinary ability and long practice." We have evidence of this in primeval men having practised a division of labour ; each man did not manufacture his own flint tools or rude pottery; but certain individuals appear to have devoted themselves to such work, no doubt receiving in exchange the produce of the chase. Archreologists are convinced that an enormous interval of time "natural selection) unreservedly to Mr. Darwin, although, as is well " known, he struck out tho idea independently, and published it, " though not with the same elaboration, at the same time." 60 Quoted by Mr. Lawson Tait in his "Law of Natural Selection," -'Dublin Quarterly Journal of Medical Science,' Feb. 1869. Dr. Keller is likewise quoted to the same effect. GrrAP.lV. , MANNER OF DEVELOPMENT. 139' elapsed before our ancestors thought. of gr~ding chipped flints into smooth tools. A man-bke ammal who possessed a hand and arm sufficiently perfect to throw a stone with precision or to form a flint into a rude tool, could it can hardly be doubted, with sufficient practice mak~ almost anything, as far as mechanical skill alone is concerned, which a civilised man can make. The structure of the hand in this respect may be compared with that of the vocal organs, which in the apes are used for uttering various signal-cries, or, as in one species, musical cadences; but in man closely similar vocal organs have become adapted through the inherited effects of use for the utterance of articulate language. Turning now to the nearest allies of man, and therefore to the best representatives of our early progenitors, we find that the hands in the Quadrumana are constructed on the same general pattern as in us, but are far less perfectly adapted for diversified uses. Their hands do not serve so well as the feet of a dog for locomotion; as may be seen in those monkeys which walk on the outer margins of the palms, or on the backs of their bent fingers, as in the chimpanzee and orang.16 Their hands, however, are admirably adapted for climbing trees. Monkeys seize thin branches or ropes, with the thumb on one side and the fingers and palm on the other side, in the same manner as we do. They can thus also carry rather large objects, such as the neck of a bottle, to their mouths. Baboons turn over stones and scratch up roots with their hands. They seize nuts, insects, or other small objects with the thumb in opposition to the fingers, and no doubt they thus extract eggs and the young from the nests . of birds. American monkeys beat the wild oranges on the 61 Owen, 'Ano.tomy of Vertebrates,' vol. iii. p. 71. |