Introduction 



E. Raymond Hall 



The University of Kansas, Lawrence 



W hen a biologist accurately depicts the geo- 

 graphic distribution of species of contemporary organisms, he does, 

 in a sense, about what the merchant does when he completes an 

 inventory of his stock of goods. When the biologist maps also the 

 geographic distribution of these same kinds, and also other kinds, of 

 organisms of the immediately preceding geological epoch, he does, 

 in a sense, what the merchant does when he examines his inventory 

 list of a year ago. Paleontology for the biologist and history of stocks 

 of goods for the merchant better than almost any other information 

 permit the biologist and merchant, respectively, to forecast what lies 

 ahead. 



For the biologist who studies evolution and its modus operandi, 

 speciation is of major importance because "species" means "kinds," 

 and the biologist has to distinguish one kind of organism from all 

 others before he can plot the distribution of any one kind. Further- 

 more, the biologist must, on the one hand, decide on a subjective 

 basis whether a particular morphological ensemble is a species or a 

 genus and, on the other hand, on an objective basis whether that 

 ensemble is a species or a subspecies. In order to decide on species 

 versus subspecies much field work, especially collecting at the right 

 places and times, is required. If the two kinds intergrade in nature, 

 they are subspecies of a single species. If the two kinds do not any- 

 where in nature intergrade, they are two species. 



Therefore, the nontaxonomist should remember when he views a 

 reasonably accurate map of the geographic distribution of an or- 

 ganism that the map represents several steps along the road to an 

 understanding of how evolution occurred in nature. 



From what the speakers showed and told and from what was 

 said in the ensuing discussion, I judge that (1) several problems have 

 been solved, but that the solution of a particular problem ordinarily 



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