OUR BEST FEATURES 



and true vision resulted, greatly enhancing the 

 organism's success in the pursuit of living prey 

 and in the escape from its enemies. Then various 

 accessory organs appeared, for regulating the focus 

 of the lens, either by slightly changing its position 

 with reference to the opening, or by altering its 

 curvature. After the air-breathing fishes crawled 

 out of the swamps their eyes had to become 

 accustomed to functioning in the air and we find 

 further improvements in the accessory devices for 

 accommodation and for protecting and keeping 

 in repair the whole delicate apparatus. These 

 devices culminate in the mammals, in which 

 however for the most part the olfactory ap- 

 paratus rather than the eyes is still the dominant 

 sense organ. The primates, alone, show a pro- 

 gressive reduction of the olfactory sense and a 

 concomitantly increasing importance of the eyes, 

 which is further emphasized in the arboreal 

 brachiating anthropoids. In man, a secondarily 

 terrestrial offshoot of the primitive anthropoid 

 stock, the eyes retain not only all the advantages 

 won by the vertebrates in their earlier predatory 

 career, but also all the improvements resulting 



from a prolonged course of very active life in the 



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