CREATION BY EVOLUTION 



The so-called wisdom teedi of man under certain condi- 

 tions partake of the nature of vestigial organs. As is well 

 known, the milk dentition of a child contains in each half 

 of each jaw two incisor or cutting teeth, one canine or eye 

 tooth, and two molars or grinding teeth, making twenty 

 milk teeth in all. When these teeth are shed a permanent 

 tooth takes the place of each milk tooth and in addition 

 three extra teeth appear in each half -jaw. These are the 

 permanent molars, and their presence increases the perma- 

 nent teeth to thirty-two. The last of these permanent molars 

 at the back of each jaw is known as the wisdom tooth. Ordi- 

 narily the wisdom teeth are cut when the person is betw^een 

 twenty and twenty-five years of age, and they get their name 

 from the belief that at that age the person has arrived at years 

 of discernment. Not a few fail to cut these teeth or, in fact, 

 even to form them at all. In such persons the number of 

 teeth is four short of the usual total. Teeth that fail to 

 cut the gums are of course useless and, in fact, like the 

 vermiform appendix, they may be worse than useless, for 

 such imperfect teeth may at times form centers of disturb- 

 ance that call for surgical treatment. 



This occasional reduction in the permanent dentition of 

 man is in a way foreshadowed by what is seen in the mon- 

 keys. The new-world monkeys have a permanent dentition 

 composed of a total of thirty-six teeth; the old-world forms, 

 including the gorilla, chimpanzee, and other anthropoid apes, 

 have four fewer permanent teeth and agree in this respect 

 with man. Man appears to be going one step farther and 

 to be reducing his dentition by dropping out another group 

 of four teeth, the wisdom teeth, a step which, if finally taken, 

 would place his permanent dental outfit at twenty-eight 

 instead of thirty-two teeth. In man wisdom teeth that fail 



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