of Man's Evolution. 



connection. Then, even if we admit that Arabia and India, as 

 well as Malaysia, might have been reachable by similar narrow 

 land routes, there was still a sea-barrier, of four to five thousand 

 miles extent, cutting off the tropical from the sub-tropical regions 

 of Asia. 



Thus the Mediterranean Sea on the one hand, and the Arabian 

 Sea, with its diverging branches up the Euphrates, Scinde, and 

 Punjab valleys, on the other, proved immense sea-barriers, which 

 must have arrested the southward migration of the anthropo- 

 morphous apes in Miocene and Pliocene times, preventing them 

 from reaching the tropical regions of the Old World, so necessary 

 to their comfort, and so well suited to their physical consti- 

 tution. 



Let us now inquire into the importance of this fact of a 

 southern sea-barrier, together with attendant physical conditions 

 on the future of anthropomorphic life. 



The gradual southward dispersal of all forms of life was due 

 to the approach of cold from the northern latitudes, distantly 

 premonitory of a coming Ice Age. Impelled southwards by cold, 

 and arrested by a southern sea-barrier, what must have been the 

 effect upon the anthropoid apes of Southern Europe and sub- 

 tropical Asia ? Those apes that were near to the narrow land 

 connections between Europe and Africa would of course escape 

 (as far as to North Africa) from the effects of approaching cold ; 

 those similarly placed in Asia would be able to save themselves 

 from like discomfort. All the rest, however,— and they must have 

 formed a vast majority — who never knew of a possible way of 

 escape, must have been obliged to remain and contend with 

 adverse circumstances. First, they would have to contend with 

 the conditions of a climate to which, for temperature, they had 

 hitherto been unaccustomed. They had to become adapted to 

 withstand a low temperature, and so develop one of the distin- 

 guishing characteristics of man, whereby he became universally 

 distributed; or else they had to perish, as soon happens with 

 apes brought from a tropical to a temperate region at the present 

 day. Here, then, was the first struggle for existence, or for the 

 development of one characteristic of man. Some, perhaps many, 

 genera of apes died out in this struggle, but others doubtless 

 were for a time successful, and were followed by a posterity 

 still more successful. It must be remembered that this change 

 from a warm to a temperate, or even cold climate, was gradual, 

 and therefore admitted of adaptation more easily than at first 

 sight might be imagined. Yet, doubtless, many genera died out, 

 unable to protract the struggle. One thing seems very probable, 

 namely, that the apes at present occupying the Equator are not 

 likely to have been derived from the stock that were obliged to 



