ADAPTATION'S AND DISTKIBL'TION 



metamorphosis (a very common occurrence in Oklahoma), the young o\ 

 frogs (Rana) and of cricket frogs ( Acris) migrate overhuid to other pools, 

 creeks, or rivers. (This applies to the bullfrog in this habitat also.) The toads, 

 however, seek softer ground and become fossorial even if very young. Indi- 

 viduals of 5. bombijrons burrow immediately upon emergence but those of 

 S. hurterii often do not do so for at least two weeks { Bragg, 1944a, 1945a). 

 Thus, habits of dispersal and methods of protection from drying differ inter- 

 specifically even in closely related taxonomic groups, differing sometimes 

 within genera (Bufo, Scaphiopus, Pseudacris). It should also be noted that 

 there is some correlation between these reactions in time and method of dis- 

 persal and the breeding pattern of adults. This is to be expected since both 

 types of behavior ha\c evolved in gradual adjustment to cn\ironment. 



Habits and Taxonomy 



The habits of an animal in its normal environment are as characteristic 

 of it as any other phase of its nature. Behavior patterns, since they are a 

 product of evolution, tend (like morphological patterns) to be distributed 

 among organisms in several ways. Broad trends in behavior can be recog- 

 nized comparable to morphological patterns used in distinctions between 

 orders, families, and other taxonomic groups. We are not surprised, there- 

 fore, to find the behavior, habits, and habit-patterns of individuals of a given 

 species overlapping, in some particulars, those of others closely or even dis- 

 tantly related to it, just as morphological patterns overlap. For example, noc- 

 turnal feeding is a characteristic of many Salientia just as truly as is the mor- 

 phological fact that some have dermal plicae. 



It should, therefore, be possible to erect a reasonably sound classification 

 of organisms on the basis of habits and habit-patterns alone, consisting of 

 higher and lower categories analogous to those based upon morphology. 

 Practical considerations have prevented the theoretically possible classifica- 

 tion from being worked out except in a few instances. See, for example, 

 Plath's (1934) attempts along this line with North American bumblebees. 



It is true that morphological characters should serve as the basis of taxo- 

 nomic distinctions wherever they can be used. But what of the cases in which 

 they fall short.? Habits and habit-patterns should be considered wherever 

 they are known to aid in understanding the life of the animal and of its 

 phylogenetic development. If habits and habit-patterns are also products of 

 evolution, these should be used with morphology in classifying organisms 

 and in studying phylogeny, which is, I believe, the goal of taxonomy. 



I do not believe that the study of habits has gone far enough as yet to 

 permit their use as more than an aid in taxonomy; but a few illustrations 

 may show some of the possibilities among the Salientia. 



( 1) Bujo woodhousii woodhousii and B. w. jowleri are so closely allied 

 that they are "practically indistinguishable except for size" (Smith, 1934). 

 Yet, habits based upon real physiological differences will partly separate 

 them. The former breeds sporadically throughout the spring and summer at 



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