312 I The Process of Evolution 



years of selection and are therefore "adapted." Often adaptation is 

 used in vague comparisons of an organism's way of life with the 

 extent of usable habitat (parasites are more "narrowly adapted" 

 than omnivores). At worst, it is used for inciting wonder at the 

 diversity of vertebrate forelimbs, bird beaks, or pollination mech- 

 anisms. (One is reminded of Lincoln's remark that his legs were, 

 miraculously, just long enough to reach the ground. ) In the former 

 instance, once the relationships are described (preferably quanti- 

 fied), the comment on adaptation seems extraneous. Under present 

 conditions, elephants cannot survive in as many places as human 

 beings. Does it really help to add that elephants are more narrowly 

 adapted than people? The continuing idea that adaptation is some 

 phlogiston-like beneficial substance that a population may possess 

 in varying quantities has been at least partly responsible for the 

 difficulties that theorists have had in coming to grips with the prob- 

 lems attendant to the question of population fitness. 



Because of the extremely loose application of the term adaptation 

 in the biological literature, it might be wise to drop it completely. 

 The many fine studies of microevolution discussed earlier (e.g., those 

 of Dobzhansky on Drosophila, Kettlewell on Biston, Clausen et al. on 

 Achillea, etc. ) are best viewed as investigations of natural selection, 

 not as studies of progressive adaptation. The populations concerned 

 are always "adapted"; at different points in time they are "adapted" 

 to diflFerent conditions. More examples of problems could be given, 

 but these should suffice to convince the reader that there are still 

 some questions left to be investigated. 



EPILOGUE 



Many scientists like to feel that they approach the world in a com- 

 pletely objective manner. For instance, a biologist may scoff at the 

 religious, saying that they accept on faith a system of beliefs that 

 cannot be put to a rational test. The scientist all too often overlooks 

 the articles of his own faith, a faith that almost always includes a 

 belief in a real world in which a sort of statistical order exists. He 

 believes that internal consistency of a theoretical construct is "good," 

 that quantification is "good," that curiosity is "good," and that cer- 

 tain kinds of logic are pertinent to his real world. He may even re- 

 sort to appeal to authority.^ Virtually all scientists dogmatically ac- 



* An outstanding recent example is: "The number of people who accept the 

 philosophy of the numerical taxonomists seems to grow despite rather severe 

 qualifications made by some of the most authoritative biologists." (S. G. 

 Kiriakoff, Systematic Zool. 11: 180, 1962.) 



