CHAPTER IX 

 THE SKELETON OF THE HIND-LIMB 



WE have seen that the human arm and hand exhibit a 

 strikingly primitive anatomical picture, and that, on 

 the whole, the resemblance of these parts of Man to the 

 same parts of the rest of the Primates is very great. We 

 have arrived at this conclusion despite the rather common 

 assumption that in the hand of Man there is evinced the 

 very highest human specialization and refinement. 

 Compared with the fore-limb, the hind-limb is apt to be 

 ranked as a rather primitive and unspecialized thing 

 in Man. This assumption, again, is contrary to all the 

 facts, for if we regard the hind-limb as presenting a 

 more primitive condition in certain Primates (and this 

 is a well- justified point of view), we must admit a very 

 definite alteration from the primitive arrangement in 

 the leg and foot of Man. The human hind-limb has 

 specialized considerably from the condition seen in the 

 arboreal Monkeys, and the arboreal hind-limb is, as we 

 shall see, far nearer to the primitive Vertebrate type. 

 Between the anatomical condition of the hind-limb of 

 the Anthropoids and that seen in Man there is apparently 

 a somewhat sudden break in the story of the evolution 

 of the leg. But the changes which ultimately become 

 so characteristic of Man are already at work in the 

 Gibbons, the Orang-utan, the Chimpanzee, and especially 

 in the Gorilla. They are already apparent in some of 

 the Old- World monkeys. 



There will be no need to discuss at all fully the anatomi- 

 cal details of the primitive hind-limb, since the likeness 

 to the fore-limb, which we have already touched on, is 

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