RETROSPECT AND PROSPECT 



ferences will disappear, and a single human race will emerge. This human 

 race of the future he has characterized on the basis of the relative con- 

 tributions which may be expected from the various races of today. Like 

 Hrdlicka, he expects the skull to be more nearly globular. In stature, he 

 expects this future race to be about like present-day southern Europeans. 

 The eyes and skin will be brown, and the hair will be straight or slightly 

 wavy. But he expects the man of the future to be much more variable than 

 any of the present races, and he hopes that some extreme variant may be 

 endowed with suJBBcient originality to cope with the major problems which 

 confront man. 



Evolution, a Young Science. Most sciences have only gradually 

 emerged from their predecessors, or from natural philosophy, but the 

 science of evolution is one of a very few for which a fairly definite time 

 of origin is known. Although the concept of origin of species by modifica- 

 tion is an ancient one, only since the publication of the "Origin of Spe- 

 cies" in 1859 has it had a firm scientific basis, capable of commanding the 

 respect of competent scientists. An oldest date of origin might be set as 

 the fall of 1834, when Darwin visited the Galapagos Islands, while the 

 latest date would be November 24, 1859, when the "Origin of Species" was 

 published. 



Once established, the new science developed very rapidly indeed. Sci- 

 entists of the latter decades of the nineteenth century labored mightily to 

 establish the fact of evolution, especially through studies in comparative 

 anatomy and comparative embryology. However, the other basic evi- 

 dences of evolution were also developed at this time, as explained above 

 in Part I. 



Yet it was not only because of the great labors of many men that the 

 new science prospered. Biology had participated in the great upsurge of 

 science in post-Renaissance times. The names of such men as Spallanzani, 

 Redi, Ray, Wolff, and Harvey serve as reminders of biological participa- 

 tion in this great movement. Yet the vast store of data which these men 

 established was largely chaotic, for there was no unified, theoretical frame- 

 work within which their diverse contributions could be marshalled. 



Linnaeus tried to fill this need with his taxonomic system, and for a time 

 he seemed to succeed in giving biology an appearance of order. In the 

 end, however, he stimulated a great deal more exploration and fact-finding 

 without satisfying the need for a basic theory, for the taxonomic system 

 itself was inexplicable. Thus Darwin found biology a burgeoning chaos of 

 more or less unrelated data without any comprehensive theory to make it 

 a cohesive whole. The theory of the origin of species by means of natural 

 selection filled that need. It gave meaning to the taxonomic system of Lin- 

 naeus and to the many other biological sciences which Linnaeus had 

 sought to clarify by his system. Today, almost all biological work is based, 

 directly or indirectly, on recognition of the fact that the plant or animal 

 of today is the most recent product of an historical process. Time has be- 

 come an essential dimension of l)iology. 



Thus the role of evolutionary theory in liiology is quite comparable to 

 that of the laws of thermodynamics in physics: it is a basic law from 



336 



