SOME ASPECTS OF THE BIOLOGY OF HUMAN POPULATIONS 537 



to make the case conclusive that population growth, if 

 undisturbed, would follow in human groups the complete 

 course of one cycle of a logistic curve. The available data 



JGOO 



:d 12.00 



^ woo 



g 800 



^ eoo 



^ 400 

 200 



1750 75 ISOO 25 50 75 1900 



Year 



Fig. 7. Observed and calculated growth of population of world. 



only make such a conclusion in some degree probable. And 

 one cannot conduct experiments with human beings on 

 this point, as can be done with lower organisms. But for- 

 tunately it has been possible to find one group of human 

 beings, the indigenous population of Algeria, in which a 

 cycle of population growth has been practically completed 

 during the period for which census records are available. 



