314 BIOLOGY FOR BEGINNERS 



while, on the other hand, most of our valuable furs are produced 

 by them. 



The Primates. This group includes the highest of the mammals, 

 and comprises the monkeys, gorilla, chimpanzee, orang-utan, 

 gibbon, marmoset, and lemur, as well as man himself. 



Their structural adaptations do not compare with those found 

 in many other orders, but the greater brain development and 

 intelligence places the primates at the head of the classification. 



This brings up again the fact that brain development is the only 

 way in which man may hope to excel. He belongs to what is called 

 a " generalized order " of animals; that is, he is not structurally 

 adapted for any particular thing, such as flight, speed, strength, 

 swimming, etc., his only claim to distinction being along the line 

 of intellectual development. 



There is nothing that man can do, if unaided by his intelligence 

 which many other animals cannot do much better; but when this 

 intelligence is at hand to direct him, there is no other animal that 

 can compete with him. 



Structurally, man resembles the higher apes very closely. Al- 

 most every detail of their anatomy is similar skeleton, muscles, 

 teeth, position of eyes, structure of the hand, and even motions 

 and facial expressions. There are, however, certain structural 

 differences such as the more erect position, shorter arms, larger 

 and better-balanced skull, higher forehead, smaller canine teeth, 

 and his inability to use the big toe like a thumb for grasping. 



These differences are utterly unimportant when compared with 

 the one great feature, the human brain. The brain of all the 

 primates is large but man's is one-third larger than the chimpanzee's 

 which most nearly approaches it in size. 



Man has learned the use of tools, devised a spoken and written 

 language, found a means of controlling fire, and developed mental 

 faculties and social habits that place him in a position far above 

 the highest apes. 



It is curious to note how three factors have contributed to man's 

 development. The erect attitude left the fore limbs free from use 

 in locomotion and permitted their development into the most 



