LIFE 683 



l.itr in the sea is less profoundly affected than that on the land, but 

 cvrn that does not escape modification. The most pronounced 

 ruvptions to man's dominance, and those that bid fair to contest 

 his supremacy longest, are found in organisms too minute to be 

 controlled easily by him, and in organisms that, quite against his 

 will, flourish on the conditions he furnishes. But even the acceler- 

 ated evolution of these organisms is a part of the profound biological 

 revolution which attends man's dominance. 



Man's control has not thus far been characterized by much 

 recognition of the complicated interrelations of organisms and of 

 the consequences of disturbing the balance in the organic kingdom, 

 and he is reaping, and is certain to reap more abundantly, the 

 unfortunate fruits of ignorant and careless action. For the most 

 part, man has been guided by immediate considerations, and even 

 these not always controlled by much intelligence. Thus great 

 wantonness has attended his destruction of both plant and animal 

 life. But a more intelligent as well as a more sympathetic attitude 

 is developing, and will doubtless soon become dominant. A new 

 era in control and selection is dawning. New varieties and races 

 are being produced that not only depart widely from the parent 

 stock, but diverge in lines chosen to meet given conditions, or to 

 produce desired products. How far this may yet go it is impossible 

 now to predict. 



Prognostic geology. The long perspective of the past should 

 afford at least some suggestions of the future, but it must be con- 

 fessed that the most important conjectures as to the future are 

 dependent on interpretations of the past that are not yet certain. 

 A word has been said relative to a possible return of a glacial epoch, 

 but no sure prediction can be made. Question has been raised as 

 to whether the deformations of recent times are over, but the 

 answer remains uncertain. The duration of the earth as a habitable 

 globe has been a common theme of prognosis. A final refrigeration 

 as the result of the cooling of a once molten globe has been the usual 

 forecast, and the final doom of the race has been a favorite theme for 

 pseudo-scientific romances. But this all hangs on the doctrine of a 

 former molten earth, if not on the doctrine of its origin from a gase- 

 ous nebula. Under the alternative conception of a slow-grown earth 

 conserving its energies, conjoined with a more generous conception 

 of the energies resident in the sun and the stellar system, no narrow 

 limit need be assigned to the habitability of the earth. A Psycho- 



