LECTURES IN BIOLOGICAL SCIENCES 



sociation areas where learning and symboling are involved in 

 the physiological control of activities like sleep, play, and sex. 

 Man is qualitatively different from other primates in that a large 

 part of sexual behavior is under symbolic, that is, cortical, rather 

 than under glandular control. The cortical control of sex makes 

 possible the cultural regulation of sexual behavior, and the sym- 

 bolic regulation of sexual behavior is one of the bases of kin- 

 ship systems and the incest taboos. The symbolic recognition 

 of social kinship (which in many human societies may depart 

 from the facts of biological kinship) makes possible the regu- 

 lating of mating, in terms both of exogamy and endogamy, and 

 these regulations make possible cooperative relationships in so- 

 cial groups larger than the biological family. Human societies 

 are the only primate societies which organize sexual behavior in 

 the interest of the economic activity of the group as well as in 

 the interest of reproduction (White, 1959; Sahlins, 1959). 



We must now examine hominid symbolic use in some detail. 



6. Systematic Symbolic Vocal Communication 



Human language, that is, systematic symbolic vocal communi- 

 cation, is an overlaid or secondary physiological function. The 

 organs of speech used in language are of quite diverse primary 

 action. The mouth, tongue, teeth, and lips had an alimentary 

 function, and the lungs and diaphragm a respiratory function, 

 long before they took a part in articulate speech. Articulate 

 speech requires the coordinated movement of about one hundred 

 muscles, most of them paired. The coordination of movement 

 in most muscles involves corrections and adjustments via pro- 

 prioceptors, the senses which tell us the position of parts of our 

 body. But the muscles working the voice box lack propriocep- 

 tive sense, and feedback control of speech comes by way of the 

 ear and the 8th cranial nerve. When we talk, the diaphragm, 

 voice box, tongue, lips, and jaw work smoothly and precisely if 

 we are to be understood. The 10th nerve controls the adjust- 

 ments of the vocal cords, and the 5th nerve controls the posi- 

 tion of the lips. Both of these use branchial muscle, while the 

 12th nerve moves the tongue with somatomotor muscle. 



Although the voice box is homologous in all primates, its 



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