A Study of Aging, Thermal Killing, and Radiation Damage by Information Theory 3 1 3 



developed in my previous article in this volume without aJ hoc assumptions. 

 Furthermore, certain interesting predictions can be made. 



Lansing's remarkable work on the rotifer is a particularly interesting 

 beginning to understanding the problems discussed in this article, if aging, 

 thermal killing, and radiation damage are really aspects of the destruction of 

 information content then there should be, as discussed above, a reciprocity 

 between the respective agents. It would be particularly interesting to know 

 if Lansing's results could be obtained by suitable x-, gamma- or ultraviolet- 

 irradiation, or also by a thermal or chemical treatment. These organisms 

 should be well adapted to this type of research. 



Among the diploid organisms, of course, mice and Drosophila are of para- 

 mount importance. It would be extremely pertinent to look for the same 

 reciprocity in this material. In addition, one should expect it to be possible, 

 given a strain of one of these animals with a rectangular survivorship curve, 

 see Fig. 5, to change it by irradiation to one of the type corresponding to 

 equation (9) in several generations. 



Acknowledgements — It is a pleasure to acknowledge the help of Dr. A. W. 

 Kimball in matters concerning the statistics of data analysis. The analysis 

 of T. H. Wood's data was greatly aided by his sending his exact experimental 

 values. Thanks are due also to Dr. Arthur C. Upton and Dr. A. W. Kimball 

 for furnishing the numerical data on the LAF^ normal aging survivorship. 

 I am very grateful to R. K. Mortimer for the use of his data. 



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