5l6 HUMAN BIOLOGY 



Before embarking upon the consideration of the biological 

 characteristics and problems of human populations it will 

 be desirable to have before us some broad statistical facts 

 about such populations. 



So far as anyone knows, the curious animal which Linnaeus 

 perhaps ironically designated Homo sapiens Hves only upon 

 one planet, the Earth (see chapter i). Nobody knows 

 exactly how many human beings are Hving on this planet at 

 this moment, or how many have been ahve upon it at any 

 other moment. Theoretically it should be a simple matter 

 to count them. Practically such a task is beset with diffi- 

 culties. What then actually happens is that at intervals of 

 five or ten year<5 as accurate counts as possible are made of 

 all those people whose aggregate state of civihzation is such 

 that any counts are feasible. Estimates are then made of 

 the numbers of the others. Roughly speaking the numbers 

 of persons hving on the earth in 1927 were of the order shown 

 in Table i. 



Table i furnishes a good deal of interesting information 

 about the number and kinds of people who are spread over 

 the earth's surface. It is seen that while Europe is only about 

 a fifteenth part of the land area of the globe, shghtly more 

 than a quarter of all the people in the world hve there. 

 Oceania has about the same area as Europe, but less than a 

 two-hundredth part of all the people hve there. Asia covers 

 less than a third of the globe but has more than half the 

 people. Africa and North America have respectively about 

 a fifth and a seventh of the area, but each has rather less 

 than a twelfth of the people. 



Plainly if Europe and Asia are to be regarded as normally 

 populated, then the rest of the world is greatly under- 

 populated. Or, conversely, if North America is held to have 

 something like an optimum population then Europe and 

 Asia are enormously overpopulated. But there is scarcely a 

 country in Europe which, at the present moment, is not 

 at least talking about the desirability of larger populations. 

 And, on the other hand, a great deal is heard in the United 

 States about the wisdom which will inhere in sharply 

 restricting the future growth of our population. In fact 



