AS THE BIOLOGIST SEES IT 



with the task that we had in common. 

 In the morning I found him dead in his 

 berth. 



What does the biologist have to tell us 

 of death? Well, first, true to his profes- 

 sional interest, he tells us of the facts and 

 the significance of the death of species. 

 He points to the hosts of extinct kinds of 

 animals, dead species, revealed by the 

 fossils in the rocks. He shows us how this 

 death of successive species reveals and 

 is itself a part of organic evolution, the 

 greatest fact, and its revelation the great- 

 est glory, in biological science. Death 

 of species is at once the revelation and 

 the proof of the struggle for existence 

 with the consequent survival of the fit. 

 Dead species have been the stepping 

 stones to new species; their history is the 

 history of organic evolution. Species are 

 unfit, or become unfit, for various rea- 

 sons; among them, the reason of over- 

 specialization. This is rather surprising, 

 for all organic evolution is a movement 

 from generalization toward specializa- 

 107 



