208 EVOLUTION IN THE PAST 



DISPERSAL the difficult question of the early dispersal of mankind. It is 

 OF MANKIND generally supposed that mankind originated on the mainland 

 of Southern Asia, formerly of vaster extent by the inclusion 

 of territory now submerged by the Arabian Sea. Owing to 

 increase of population a dispersal, in course of time, must 

 have taken place ; and men, brought under various climatic 

 and other conditions, gradually differentiated into three 

 groups, known as Negroid or Black, Mongolian or Yellow, 

 and Caucasian or White. 



MIGRATION One migratory movement from the cradle-land pursued, 

 TO AUSTRALIA no doubt, a south-easterly direction across the East Indian 

 Archipelago. In course of time some of the wanderers, it 

 may be supposed, reached New Guinea, and thence crossed 

 the Torres Strait to Australia. These emigrants, at the time 

 of their arrival in Australia, may not have been already 

 " blacks " ; but it is reasonable to assume that they were 

 well on the way to becoming so. 



In the opinion of many, the Tasmanians, who became 

 extinct in 1876, were descendants of the men that first 

 reached Australia. Their presence in Tasmania was caused, 

 it is supposed, by their ancestors having been gradually 

 forced south by the arrival in Australia of a second Asiatic 

 horde or race. These second invaders blended possibly with 

 some of the earlier race are now represented, it is thought, 

 by the Australian aborigines. 



These migrations did not bring any laurels to humanity. 

 The Tasmanians never showed any signs of becoming civil- 

 ised ; and the Australian aborigines are the lowest of savages. 

 Indeed, it is doubtful if they are in a much higher state of 

 culture than were the inter-glacial hunters. The cause is not 

 far to seek. By long isolation the animal life of Australia had 

 remained in a lowly condition of development ; and so the 

 aborigines of old, away from " the great world," with its 

 denser populations, and keener competitions, lost all share in 

 its evolving civilisation. 



MIGRATIONS Another migration from the cradle-land led to the peopling 



TO CENTRAL of Africa south of the Sahara. These wanderers, coming 



AND SOUTH- across the land now submerged by the Arabian Sea, spread 



ERN AFRICA over various districts of the " dark " continent, and gave 



