466 ON OUR PRESENT KNOWLEDGE OF THE ORIGIN OF MAN. 



of extinct Old- World apes; the more recent ancestors of this series 

 belonged to the group of tailless anthropoid apes with five sacral ver- 

 tebine {Anthropoides), the older ancestors to the group of the tailed 

 baboons with three or four sacral vertebra? (Gynopitheca). These four 

 propositions are, according to our conviction, unalterably settled, no 

 matter what further anatomical or pakeontological discoveries may 

 later do to clear up the particulars of the many steps of the phyletic 

 evolution of man. 



Comparative anatomy, which, with critical penetration, examines 

 analytically on the one hand the structural differences of separate 

 species of animals, and on the other systematically groups them in 

 natural order according to their common characters, has completely 

 demonstrated the validity of our pithecometric proposition and its 

 significant inferences. Not less important than these morphological 

 considerations are the physiological ones that are taught us by that 

 instructive but hitherto, alas! too much neglected science, compara- 

 tive physiology. For an unprejudiced comparison of all the activities 

 of life teaches us that in this department also there is nowhere any 

 radical distinction between man and apes. Our entire nutrition, secre- 

 tion and circulation, breathing and digestion, are performed by the 

 same physical and chemical processes as with the anthropoid apes. It 

 is the same with the isolated processes of sexual activities and propa- 

 gation. It is the same also for the animal functions of movement and 

 sensation. Our mental ability results from the same physical and 

 chemical laws as does that of the apes. The mechanics of our bony 

 frame and the movements our muscles impart to this arrangement of 

 levers are in no way different in man and the anthropoid apes. It was 

 formerly thought that walking erect was a special attribute of man. 

 We now know that this can sometimes be done by the gorilla and the 

 chimpanzee, and especially by the gibbon. 



It is quite the same with human speech. The various sounds by 

 which apes express their sensations and their wishes, their affection, 

 and aversion must by comparative physiology be considered as speech, 

 just as much as are the similarly imperfect sounds that children make 

 when learning to talk, and as the manifold tones by meansof which 

 social mammals and birds impart to each other their ideas. The mod- 

 ulated song of the singing bird belongs to speech just as much as the 

 similar song of man. Besides, there exists a musical anthropoid. The 

 singing gibbon or siamang {Hylobates syndactylus) begins with the fun- 

 damental tone E and goes upward through the entire chromatic scale, 

 a full octave, in pure and sonorous half tones. The old doctrine that 

 only man is endowed with speech and reason is still to-day held by 

 some authoritative philologists, as, for example, Max Miiller at Oxford. 

 It is high lime that this erroneous impression, resting on a lack of 

 zoological information, should be abandoned. 



Our pithecometric proposition met with the greatest difficulties and 



