CHAPTER IX 



OBJECTIONS TO THE HYPOTHESIS 



Very many objections and criticisms have already been pub- 

 lished, and many more are doubtless to follow. A consideration 

 of them, however, shows that in general they are based upon a 

 few general principles, and that a proper understanding of Age 

 and Area, and of the provisos with which it is hedged round, 

 will go far to remove the most of them. 



The first few, (1) that the numerical results are accidental^ 

 (2) that the figures are not reliable, and will be vitiated by 

 further Avork, and (3) that the figiu-es can be accounted for by 

 changes in climate and configuration of the countries concerned, 

 require no discussion at the stage which Age and Area has now 

 reached. Far too many facts have been accumulated from too 

 many places, to leave room for them to be seriously advanced. 

 Another, (4) that the hypothesis is an assumption, has really 

 little bearing upon the matter. Natural Selection, and many 

 other fruitful hypotheses, are also assumptions, and Age and 

 Area has already led to new discovery. 



Some writers show a confusion of thought between (5) en- 

 demism and endemic species. The former, if it occur in a country, 

 is a sign of age, for time must be allowed for it to appear; but 

 the endemic species are in genei-al the youngest in the country, 

 in their own groups of afiinity. 



Some say (6) that the wide dispersal of the wides is diie to 

 their wide dispersal outside the country, but give no reason for 

 this. It utterly fails, however, to explain the graduated dis- 

 tribution of the wides, those that occur farthest away showing 

 (on the average) the maximum local dispersal (cf. the Ceylon- 

 Peninsular-Indian species with the wides of greater range, or 

 the species that reach the outlying islands of New Zealand with 

 those that do not). To explain such cases the most improbable 

 supplementary hypotheses have to be adduced (126, p. 10). 



A number of objections arise from the attempt to apply Age 

 and Area to individual cases; such are (7) that there are many 

 exceptions^ — species whose area does not at all represent their 

 age, and the like, (8) tliat species may die out or be killed out in 

 part of their area, (9) that one cannot properly compare a single 



