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Other tests of this hypothesis have involved studies of the minimum 

 distances apart at which one can break a chromosome or alter it to form 

 various alleles. Best estimates place this at about the length along the 

 DNA helix of one rung. Likewise, experiments with fractured bacterial 

 DNA indicate that pieces as small as 4 rungs may still carry information. 

 This would be just 2 bits more than is necessary to specify one amino 

 acid. 



The language of information theory makes it easier to understand the 

 transmission of genetic information • during reproduction. It empha- 

 sizes the coding problem along the DNA, focusing attention in that 

 particular direction. Information theory is a language. It cannot in 

 itself find the coding system. 



6. Summary 



It has been shown that the language of information theory can be used 

 in various fields of biology. Information theory emphasizes the quantita- 

 tive, mathematical approach appealing to the physicist. Information 

 theory is a successful language in that it increases the rate of trans- 

 mission of information from one person to another and helps focus 

 research thoughts in new directions. It is a new language and as yet 

 a far less successful language in biology than calculus is in physics. 



REFERENCES 



1. Goldman, Stanford, Information Theory (Englewood Cliffs, N.J.: Prentice- 

 Hall, Inc., 1953). 



2. Quastler, H., ed., Essays on the Use of Information Theory in Biology (Urbana, 

 Illinois: University of Illinois Press, 1953). 



3. Shannon, C. E., and Warren Weaver, Mathematical Theory of Communications, 

 and Recent Contributions to the Mathematical Theory of Communication (Urbana, 

 Illinois: University of Illinois Press, 1949). This is the "classical" book in 

 the field. 



4. Yockey, H. P., R. L. Platzman, and H. Quastler, Symposium on Information 

 Theory in Biology (New York: Pergamon Press, 1958). 



5. Elsasser, W. M., The Physical Foundation of Biology (New York: Pergamon 

 Press, 1959). 



Many journal articles and recent publications deal with the applications of 

 information theory to biology. The following three are among the earlier 

 ones on information theory and perception : 



6. Jacobsen, Homer, "Information and the Human Ear," J. Acous. Soc. Am. 

 23: 463-471 (July 1951). 



