EVOLUTION OF THE HUMAN SPECIES 185 



specialists agree fall directly into line with those estab- 

 lished elsewhere in zoology. It seems best to state 

 these principles without reverting to controversial mat- 

 ters which find their place in the monographs of the 

 experts. Any comprehensive account such as that of 

 Keane, even if it may not give the final word, will be 

 entirely sufficient to demonstrate how fruitful are the 

 methods of evolution when they are employed for the 

 study of human races, and indeed how impossible it is 

 to discuss human histories without finding conclusive 

 evidences of their evolutionary nature. 



The facts that are available indicate that the first 

 members of our species evolved in an equatorial conti- 

 nent which is now submerged, and which occupied a 

 position between the present continents of Asia and 

 Africa. From this center hordes of primitive men 

 migrated to distant centers where they differentiated 

 into three primary and distinct groups. The first of 

 these was gradually resolved into the darker-skinned 

 peoples most of whom now live in the continent of 

 Africa, although many dwell also in the islands of the 

 western Pacific Ocean. The second branch divided 

 almost immediately to produce, on the one hand, the 

 Indians of the new world and, on the other, the yellow- 

 skinned inhabitants of Asia and other places. The 

 third branch developed as such in the neighborhood of 

 the Mediterranean Sea, and produced the series of 

 so-called Caucasian peoples, which are by far the most 

 familiar to us and to which most of us belong. But 

 so early did the second branch divide that there are 

 virtually four main divisions of the human species that 

 are to be examined in serial order. 



