3 



Special Uses of Hearing 

 and Vision 



I. introduction 



Biophysicists have, in one fashion or another, been interested in many 

 sensory systems including hearing, vision, olfaction, taste, touch, tempera- 

 ture, pain, proprioception, and time. All are contained in the human 

 body. There is no reason to suppose that some living organisms could 

 not be sensitive to types of stimuli other than those to which humans 

 respond, such as magnetic fields or even neutron beams. All experi- 

 ments to date, however, tend to confirm that the types of sensory mechan- 

 isms active in humans are the only important ones in other living 

 organisms. The differences which do exist involve quantitative aspects 

 such as the frequency range of hearing, the wavelength band of vision, 

 and the particular chemicals to which an organism responds. It is 

 conceivable, nonetheless, that the failure to find other sensory systems 

 may reflect our ignorance rather than their nonexistence. 



In spite of our inability to detect basically different systems, there are 

 many novel ways in which the known sensations are used. For example, 



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