Leciure III 



HUMAN LONGEVITY 



In the first of these lectures it was pointed out that one of the 

 important characteristics that set man apart as the unique mam- 

 mal was his great individual longevity — greater than that of 

 any other mammal. It was promised that this characteristic 

 would be given special discussion in due course. The present 

 lecture aims to redeem that promise. To do this we must first 

 justify the categorical statement that man has in fact the longest 

 life span of any mammal. This is quite easy to do, because there 

 is but one contender against him for the position of supremacy 

 in longevity. That is the elephant. There has long prevailed a 

 popular belief that the elephant is fabulously long-lived. This 

 is only a myth, however, quite unsupported by quantitative rec- 

 ords. On the contrary all the available evidence agrees on two 

 points: first, that elephants under domestication, about which 

 India furnishes long and extensive experience, live on the av- 

 erage longer than in the wild state j and second, that few individ- 

 uals tame or wild ever live more than 50 years, and for those 

 few reliable evidence is lacking that any ever achieves more 

 than about eighty years of life as an outside maximum. The 

 case is different with man, as we shall now see. 



The available evidence indicates that during the last twenty- 

 four hours something upwards of a sixth of a million fresh new 

 human beings have appeared for the first time upon this earth as 

 a whole. Each of these babies that starts today on the journey 

 through time called the life span will endeavor, with all its 

 might and main, to make that journey last just as long as pos- 



47 



