BODILY CHARACTERISTICS OP MAN. 145 



circumstances strongly call for their exercise. This power of 

 adaptation to varieties in external conditions, which makes him 

 to a great extent independent of them, is manifested in other 

 features of his structure and economy. He is capable of sus- 

 taining the lowest, as well as the highest, extremes of atmo- 

 spheric pressure ; and in this respect he is strikingly contrasted 

 with the Quadrumana, to all of which a warm climate is a 

 necessary condition of their existence. Thus the Chimpanzee is 

 restricted to the hottest parts of Africa, and the Orang Outan 

 is only found in Borneo and Sumatra; they cannot be kept 

 alive in temperate climates without the assistance of artificial 

 heat ; and even when this is afforded, they speedily become 

 diseased and die. The diet of Man, as indicated alike by the 

 conformation of his teeth and digestive apparatus, and by his 

 natural tastes, is properly of a mixed kind ; but he may sup- 

 port himself in health and strength on animal or vegetable food 

 exclusively. It is partly to this capability of adaptation, that 

 we are to attribute the various modifications of his form and 

 external appearance, which are so remarkable in the various 

 races that inhabit different parts of the globe. Some of these 

 will be presently noticed. 



135. The slow growth of Man, and the length of time during 

 which he remains in a state of dependance upon his parents, are 

 additional characters, by which he is distinguished from other 

 animals, and which are closely connected with his ultimate 

 superiority over them. He is unable to seek his own food 

 during at least the three first years of his life ; and he does 

 not attain his full stature, until he is more than twenty years of 

 age. This circumstance influences all the relations of parent 

 and offspring ; and is closely connected with that association of 

 the members of the same family, and that continued affection 

 amongst them, which we have no reason to regard as existing 

 among any other animals. In proportion to his size, the dura- 

 tion of the life of Man is greater than that of other Mammalia. 

 The greatest age of the Horse, for example, which is an animal 

 of much superior bulk, is between thirty and forty years ; that 

 of the Orang, which, when full grown, surpasses Man in stature, 



