76 THE DESCENT OF MAN 



burs, and hunt for each other's parasites. They roll down 

 stones, or throw them at their enemies: nevertheless, they 

 are clumsy in these various actions, and, as I have myself 

 seen, are quite unable to throw a stone with precision. 



It seems to me far from true that because "objects are 

 grasped clumsily" by monkeys, "a much less specialized 

 organ of prehension" would have served them" equally 

 well with their present hands. On the contrary, I see no 

 reason to doubt that more perfectly constructed hands would 

 have been an advantage to them, provided that they were 

 not thus rendered less fitted for climbing trees. We may 

 suspect that a hand as perfect as that of man would have 

 been disadvantageous for climbing, for the most arboreal 

 monkeys in the world, namely, Ateles in America, Colobus 

 in Africa, and Hylobates in Asia, are either thumbless, or 

 their toes partially cohere, so that their limbs are converted 

 into mere grasping hooks." 



As soon as some ancient member in the great series of the 

 Primates tcame to be less arboreal, owing to a change in its 

 manner of procuring subsistence, or to some change in the 

 surrounding conditions, its habitual manner of progression 

 would have been modified; and thus it would have been 

 rendered more strictly quadrupedal or bipedal. Baboons 

 frequent hilly and rocky districts, and only' from necessity 

 climb high trees;" and they have acquired almost the gait 

 of a dog. Man alone has become a biped; and we can, I 

 think, partly see how he has come to assume his erect atti- 

 tude, which forms one of his most conspicuous characters. 

 Man cpuld not have attained -his present dominant position 

 in the world without the use of his hands, which are so ad- 



™. "Quarterly Review," April, 1869, p. 392. 



" In Eylobates syndactylus, as the name expresses, two of the toes regu- 

 larly cohere; and this, as Mr. Blyth informs me, is occasionally the ease with 

 the toes of H. agUis, lar, and leueiscus. Colobus Is strictly arboreal and 

 extraordinarily active (Brehm, "Thierleben, " B. i. s. 50), but whether a better 

 climber than the species of the allied genera, I do not know. It deserves 

 notice that the feet of the sloths, the most arboreal animals in the world, are 

 wonderfully hooklike. 



"" Brehm, "Thierleben, '' B. i. s. 80. 



