CHAPTER VI 



RELATIONS BETWEEN ANIMALS AND 

 PLANTS 



Interrelationships between animals and plants 

 may be divided into that class in which the animal 

 is dependent on the plant, and that in which the 

 plant depends upon the animal. The first group 

 of relationships is the larger, in deserts as in other 

 types of environment. AU the world over it is 

 true that the animal depends on the plant for 

 compounds of nitrogen and compounds of carbon : 

 most of the essential food of every Uving animal 

 comes directly or indirectly from plants, and with 

 it the animal swallows a proportion of water. The 

 plants also fulfil certain subsidiary functions with 

 regard to the animals; they furnish them with 

 shelter from the elements, and protection from 

 enemies. One may therefore say in general terms 

 that the plant provides the animal with food and 

 water, and with shelter and protection. 



It is convenient to consider at one time the food 

 and the water which animals in deserts derive 

 from the plants which they eat. The food and 

 water are swallowed together, and may for the 

 moment be regarded as a single contribution made 



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