CHAPTER VI 



THE PRIMATES (EXCEPT MAN) 



General features of the order — Its Eocene history — Tarsiidae 

 and Adapidae — The Lemurs — Recent change of life habits 

 in Lemur catta — Extreme Rodent adaptation in Aye-aye — 

 Parallel evolution in Primates — Importance and early oc- 

 currence of reduction in incisor series — Herbivorous adap- 

 tation in some New-World Monkeys — Ancestry of Old- 

 World Monkeys and Apes — Parapithecus — Commencing 

 herbivorous adaptation in Lasiopyga— Completely herbiv- 

 orous forms — Papio — The Langurs and Guerezas — An- 

 cestors of the Anthropoids — Position of the modern Gib- 

 bons — The black Anthropoids, Gorilla and Chimpanzee — 

 The red Anthropoid, Orang — Frugivorous adaptation in 

 Orang — Summary of features of the Anthropoid dentition. 



The Primates, a varied assemblage of Mammals, most of 

 them arboreal in habit, are especially interesting since the 

 order includes Man himself. Our closest relations are the 

 great Anthropoids, the Gorilla, the Chimpanzee and the Orang. 

 Further removed is the small Anthropoid, the Gibbon. The 

 Old-World Apes and Monkeys represent a more distant branch 

 of Primate stock but further still removed are the American 

 Monkeys. The Lemurs, for the most part highly specialized 

 and even retrogressive, stand so distinctly by themselves that- 

 many authors deny their right to inclusion within the order. 



In studying these animals it is quite important to remember 

 that they do not represent a steady succession with Man him- 

 self as the culmination but each family having derived its 

 origin from some primitive ancestor has specialized along its 

 own line which however has run more or less parallel during 



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