THE AMPHIBIA OF OKLAHOMA 



The emphasis on structure and the neglect of habits has given rise in 

 some quarters to an unfortunate error, namely of expecting the habits of 

 organisms always to correspond to their taxonomic arrangement. Because 

 the better known eastern frogs and toads all have a definite breeding season, 

 it is often assumed that most or all species in North America have one. Wit- 

 ness the peculiar interest among the earlier observers, sometimes approaching 

 amazement, concerning the habits of the eastern spadefoot (Scaphiopus h. 

 holbvookji HarlanJ which does not behave in an "orthodox" manner. But 

 once it was determined that this form is different, it was expected that other 

 spadefoots are necessarily like it in its peculiarities; and some notions about 

 these animals have developed which have no foundation in fact (see Bragg, 

 1944a, for a more extended discussion of this point.) 



The almost universal reliance upon the experimental method has also 

 caused some confusion. Davis (1936) gives emphasis to this fact as follows: 

 "The most satisfactory approach to a study of the courtship behavior of ani- 

 mals is direct observation, preferably of undisturbed individuals in the field. 

 Serious misinterpretations have not infrequently arisen from observation or 

 experimentation on captive material, where unnatural associations almost in- 

 evitably alter behavior." What this author here states for courtship behavior, 

 I hold to be true to some extent in all behavior. Animals segregated under 

 experimental conditions do not always or necessarily behave in the same 

 manner as in nature, and we never can be sure, even though in 90 per cent 

 of the cases the field work may confirm the laboratory, that results obtained 

 by these methods are valid in nature without field observations to check them. 

 Furthermore, in the open, experimental control is at most very difficult and 

 usually impossible to secure, and the experimental method, because it is based 

 upon controlled conditions, is of very limited application in nature. Not only 

 this, but control is often actually undesirable; for under natural conditions 

 many factors work together to produce a given effect, each modifying the 

 others in complex, interrelated ways. From an ecological point of view, it is 

 exactly these interrelations of physiological and environmental conditions 

 which we wish to know. In other words, experimentation, valuable as it is, 

 like other methods, has its limitations, and, in the particular problem at hand, 

 overemphasis or reliance upon it may lead one astray. Simple observation 

 still has its place in science, even though it lacks the precision of 

 experimentation. 



The present series of papers, of which this is the seventeenth and last, 

 has dealt with many phases in the lives of most of the frogs and toads in Okla- 

 homa. Some have been rather extensive analyses of field observations upon a 

 single species; others have dealt with some one phase in the lives of several 

 species; still others have been mere notes on interesting points. All have em- 

 phasized habits in relation to environment and all have been essentially obser- 

 vational rather than experimental. The present contribution summarizes the 

 work on adaptation to the various environments present in Oklahoma and 

 adjacent regions. The intent is to generalize so far as seems justified by the 

 observations without becoming confused by the multitutlinous details. Habits 



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