682 THE HUMAN PERIOD 



intercommunication, and hence against the development of a 

 common cosmopolitan type. So long as hunting and fishing were 

 the dominant pursuits, a wider and wider dispersion into small 

 tribes was a necessary tendency. That such artificial sources of 

 provincialism were more effective than natural ones seems to be 

 implied by the fact that while physiological differences sufficiently 

 marked readily to characterize varieties are numbered by hundreds, 

 dialects sufficiently different to prevent free intercourse are num- 

 bered by thousands. Provincial sentiment to-day manifests itself 

 more conspicuously in language than in most other ways. 



When efficient water-transportation was developed and the 

 control of the sea attained, a period of cosmopolitan tendency was 

 inaugurated. This has been greatly accelerated in the last few 

 decades, supplemented by rapid land-transportation and electric 

 communication, and is rapidly involving the whole race in a cosmo- 

 politan movement. Almost the whole world is already in daily 

 communication, and most races are more or less habitually inter- 

 mingling by travel and trade. That this is to become more and 

 more habitual until the whole race shall be in constant inter- 

 communication, is not to be questioned. There will then have 

 been inaugurated the most marked period of cosmopolitanism, in 

 all senses of the term, which the world has ever witnessed. What 

 all this will ultimately mean for the race we do not venture to 

 predict. 



Man as a geological agency. The earlier geologists were in- 

 clined to regard man's agency in geological progress as rather 

 trivial, perhaps because physiographic geology, in which his influ- 

 ence is felt chiefly, was then less studied than other phases with 

 which he has little to do. The fact probably is that no previous 

 agent, in an equal period of time, has so greatly influenced the life 

 of the land, or the rate of land-degradation, as man has since the 

 agricultural epoch was well established. That this influence will 

 be increased during coming centuries seems clear. The flora is 

 rapidly passing from that which had been evolved by natural 

 agencies through the ages, to that which man selects for cultivation 

 or preservation. With the further progress of this movement, 

 native floras seem destined to early extinction. The same may 

 be said of native faunas. Favored animals, under man's care, 

 flourish beyond precedent, while others, so far as they are within his 

 reach, are suffering rapid declines that look toward extinction. 



