AND PERSONALITY 



blooded, has correspondingly a lack of energy for perform- 

 ing more than the simplest acts required for securing food. 

 Since its habitat is the swamp or the long grass, the reptile 

 depends largely upon concealment for survival. The energy 

 equipment of the ostrich, like the energy equipment of 

 the reptiles, shows little development of intelligence or 

 association centers. It would take little intelligence to pick 

 up the small snakes and lizards on the wide plain. Were 

 the reptile warm-blooded, it could perform many acts to 

 its advantage, but to perform such acts the reptile would 

 require a corresponding mass of brain for "thinking." 



Since, by virtue of the large ratio of surface to mass, the 

 smaller the animal the greater its protection against heat- 

 stroke, a sparrow can support a body temperature as high 

 as 112 without heatstroke. Were the ostrich to attain such 

 a degree of temperature, it would die of heatstroke. The 

 sparrow's advantage in having a temperature 12 higher 

 than that of the ostrich is that in its mental and muscular 

 actions the sparrow can be 120 per cent quicker than the 

 ostrich. 



Between the high intelligence of the sparrow and the low 

 intelligence of the crocodile or the alligator there intervenes 

 the intermediate intelligence of the ostrich. The mechanism 

 of intelligence will be discussed in a later chapter. 



The brain of a robin or a crow, like the brain of a 

 sparrow, shows a well developed mechanism for " thinking." 

 What seems to be instinct in the bird is more likely an 

 ability for quick thinking, an awareness of an end or object 

 to be gained. Before there are leaves on a tree in the spring 

 a robin flits from limb to limb, looking this way and that 

 until it decides where to build its nest. The robin, meantime, 

 must prevision the leaves that have not yet appeared. It 

 must perform an accurate job of engineering in placing the 

 nest in a safe position with regard to the wind and storm, 

 to snakes and marauding land animals, and to its enemies of 

 the air. This accurate piece of engineering is done by the 



