THINKING ABOUT RACE — WASHBURN 369 



velopment seems to have been in the Congo and West Africa. The 

 Bushmen occupied South Africa and formerly a good deal of East 

 Africa as well. The Australian-Melanesian group occupied Australia, 

 New Guinea, and adjacent islands. The Polynesians were late comers 

 to the island area (the era of the great migrations seems to have started 

 about A.D. 800). The Mongoloids were located in Eastern Asia and 

 migrated into the Americas where they probably absorbed the earlier 

 type of Upper Palaeolithic man. 



If such an hypothesis is correct, as many scientists think, the area 

 where the greatest mixing has occurred and which is hardest to classify 

 should be the most central one, that is, India. 



Dispersal followed by the establishment of local varieties has been 

 called adaptive radiation. It has been shown to apply to numerous 

 mammalian groups and seems to apply equally well to man (Howells, 

 1942) . However, after the dispersion of modern man, the development 

 of agriculture and the enormous subsequent increase in population soon 

 changed matters. Childe (1939) has written a most stimulating book 

 on the relation of civilization to population. The population of the 

 world increased from some 7 million in the hunting stage to over 2 

 billion at the present time. As far as race is concerned, the result of 

 this enormous increase has been the loss of biological isolation (How- 

 ells, op. cit.). Small numbers and isolation seem to be necessary for 

 the establishment of new types. These conditions changed greatly after 

 the introduction of agriculture and disappeared with the fabulous in- 

 crease in population which followed the industrial revolution. 



At present the characters of world population are being determined 

 largely by mixture and differential birth rates. It is hard to see how 

 new racial types can form under present conditions. It should be 

 noted that the later phases of human evolution introduced new factors. 

 While the earlier phases of man's biological progress can be treated 

 just like those of any mammal, the later demand a knowledge of social 

 factors. It is for this reason that social and biological scientists must 

 cooperate in the study of man. 



Granting that there was a dispersal of a rugged, generalized, mod- 

 ern man, from what type of man was he derived ? There is no question 

 upon which there is less agreement among students of human evolu- 

 tion. Some maintain that the modern type is of great antiquity 

 (Galley Hill, Swanscombe skulls lend support to this view). Others 

 feel that modern man is recent. The prevalence of other more primi- 

 tive types until the latter part of the Ice Age, and the sudden spread 

 of modern man at that time corroborates this hypothesis (to which the 

 writer leans). However, there seems little doubt that the earlier 

 Neanderthal men (Galilee, Ehringsdorf, Skhul 5, Steinheim; see 



