Molars 



Incisors 



Incisors 



Horse 



Cow 



Molars J^^rs 



Giraffe 



Molars 



Elephant 



THE TEETH OF HERBIVOROUS ANIMALS 



The sharp incisors cut or tear the leafy material. The broad grinding surfaces of the 

 molars macerate or shred the food 



yet ferocious behavior effective in capturing and killing prey. The weapons 

 of wolves and other members of the dog family are similar, but their hunt- 

 ing habits are different. 



Among the birds there is a great range in size, from the humming-bird, 

 which weighs less than an ounce, to the ostrich, which may attain a weight 

 of over 200 pounds. There is a corresponding range in foods, from the 

 nectar of flowers and insects caught on the wing to nuts and fruits, frogs, 

 rabbits, sheep, and even larger animals (when dead), as in the case of the 

 buzzards. And there are corresponding types of beaks and also of feet. 



The great French anatomist Georges Cuvier (1769-1832) found the vari- 

 ous organs of the birds which he studied so closely related to the ways of 

 life that he was able to tell a great deal about the habits of an unknown 

 species from examining merely one of the bones (see illustration, p. 178). 



Birds, like ruminants, cannot stop to chew, but gulp their food. Many 

 also store the swallowed mass temporarily, in a pouched enlargement of the 

 food tube called the crop (see illustration, p. 173). Birds swallow small 

 stones into a muscular grinding organ called the gizzard. Food passes 

 quickly through the relatively short digestive tract of birds, 



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