INTELLIGENCE, POWER, 



mating. In contrasting the energy systems of these two 

 animals, let us keep in mind the high speed and kicking 

 force of an ostrich compared with the lethargy and somno- 

 lence of a crocodile. Let us recall the large, bright eye of 

 the ostrich and the small, dull eye of the crocodile. Dissec- 

 tion of the crocodile showed the weight of the brain to be 

 15.6 grams. The weight of the brain of the warm-blooded 

 ostrich was 42.11 grams nearly three times the weight of 

 the brain of the crocodile. 



The brain of the crocodile consisted largely of olfactory 

 and optic lobes. It is principally through smelling that the 

 crocodile senses its prey. "Thinking" plays little part in 

 this great reptile. Whereas the ostrich appears to be eye- 

 controlled, studies of the brains of both crocodiles and 

 alligators show the crocodile and the alligator to be largely 

 smell-controlled mechanisms. The greater part of the entire 

 brain of both the crocodile and the alligator consists of 

 olfactory receptors, olfactory nerves, and the olfactory 

 lobe. Therefore, in both the crocodile and the alligator we 

 have a mechanism that is largely driven by the sense of 

 smell. The bird has little or no sense of smell, and its 

 olfactory lobes are slightly developed. The sense of smell is 

 highly important to the crocodile but practically unimpor- 

 tant to the bird. 



Throughout nature we frequently see compensation. If 

 an organ such as the eye is very highly developed, as it is in 

 the case of the bird, the sense of smell is accordingly 

 diminished. If, on the other hand, the sense of smell is 

 highly developed, as it is in the case of the reptile, the sense 

 of sight is diminished. In evolution the sense having the 

 greatest survival value is paramount. 



The most important characteristic of the brains of these 

 large reptiles is the almost complete absence of the associa- 

 tion tracts or "thinking brain." To a certain extent the 

 simple pattern of the brain found in the crocodile and the 

 alligator is seen in all the reptiles. The reptile, being cold- 



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