OUR BEST FEATURES 



they are literally one of the earmarks of man's 

 relatively close relationship to the primitive brachi- 

 ating ancestors of the chimpanzee-gorilla stock. 

 If man had been derived from some entirely differ- 

 ent stock of Primates there is no assignable reason 

 why he should resemble the gorilla and the chim- 

 panzee in so many external and internal characters 

 in spite of his widely different habits and notwith- 

 standing the millions of years that have passed 

 since the human and gorilla-chimpanzee groups 

 began to separate. 



Since the time of Darwin the reduced ear 

 muscles of man have been justly famous as indi- 

 cations of our derivation from mammals with 

 more movable ears. Ruge's monograph (1887, 

 Plates V, VI, VII) on the facial musculature shows 

 very clearly the striking resemblance between the 

 ear muscles of the chimpanzee and those of certain 

 human embryos and children {cj. also Fig. ^3D, E) . 

 =^The evolution of the auditory ossicles (Fig. Ill) 

 has been referred to earlier in this book but may 

 be summarized here as follows. The most ancient 

 member of the ossicular chain is the stapes, or 

 stirrup, which has probably been derived from 



one of the two upper segments of the second or 



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