618 



ANNUAL EEPORT SMITHSONIAN INSTITUTION, 192 8 



glacial periods, does not harmonize well with either the paleontologi- 

 cal or the human evidence. Both the,se tend to show but one main 

 interglacial interval, from which there is a gradual progression 

 toward an irregular cold period, after which follows an irregular 

 postglacial. There is no warm fauna that would correspond to the 

 assumed third (Kiss-Wiirm) interglacial. And there is evident no 

 substantial change, such as would necessarily be brought about by a 

 marked alteration in climate, in man'^ housing and living habits from 

 the Middle Mousterian to the Magdalcnian cultural periods. 



(2) The Mousterian or Neanderthal phase of man begins toward 

 the end of the warm main interglacial. It is essentially the period 



}-J o Vno 



yi. -ia|>i.C-H3 



vlo\vio £ a)ii.Q y\s. 



H • 'nta.vuia.nllia,hi\m 



7t C K tc a.Vi. t ti 10 k u. J 



FiGUKE 6. — Various conceptions as to the phylogenetic relation of Neanderthal and 

 later man. (Present evidence favors the view represented on the extreme right) 



of the cooling stage of the terminal main jce invasion, reaching to, 

 and probably somewhat beyond, its culmination. 



(3) During this period man is brought face to face with great 

 changes of environment. He is gradually confronted with hard 

 winters, which demand more shelter, more clothing, more food, more 

 fire, and storage of provisions; there are changes in the fauna which 

 call for new adaptations and developments in hunting; and there 

 are growing discomforts with, it may be assumed, increasing respira- 

 tory and other diseases, that call for new efforts and seriously hinder 

 the growth of the population. 



(4) Such a major change in the principal environmental factors 

 must inevitably have brought about, on the one hand, greater mental 

 as well as physical exertion and, on the other hand, an intensification 

 of natural selection, with the survival of only the more, and perish- 



