NO. 4 AVIAN GENUS CLAMATOR — FRIEDMANN 95 



The original Clamator stock, as represented by C. jacohintis ser- 

 ratus had a tendency toward plumage polymorphism, a trend that 

 could, potentially, enhance the process of subsequent differentiation 

 into discrete taxonomic entities. This polymorphism remained 

 localized in the ancestral home — southeastern Africa — although traces 

 of the tendency still occasionally crop up elsewhere in African 

 jacobinus and, strangely enough, in a very limited portion of its 

 range, in levaillantii. No trace of polymorphism has been found in 

 Asiatic jacobinus, in coromandus, or in glandarius. The lack of evo- 

 lutionary consequences of this early polymorphism is due to the fact 

 of its neutral nature. 



The variations in "normal" plumages show clearly that levaillantii 

 was derived from jacobinus; the phylogenetically conservative tend- 

 ency of Juvenal plumage characters indicates that glandarius arose 

 from a corojnandus-like stock. The fact that Clamator, during its 

 very long existence, has produced only 4 species, as against 12 in 

 the younger Cuculus, or 12 in Chrysococcyx (including "Chalcites"), 

 coupled with the evolutionarily inert nature of its polymorphic trends, 

 suggests that the genus is one that has been relatively less affected 

 by evolutionary change. 



Similarly, migratory behavior has remained less completely formu- 

 lated and less rigid in its manifestations in many sections of the 

 genus, even varying markedly in different segments of individual 

 species. We have noted the entire range of behavior from absence of 

 migration to local migration, to partial migration, to total and regular 

 seasonal mass movements of great geographic extent. 



We must remember that, like other organisms, birds, their struc- 

 tures and their habits, do not evolve ; they are evolved. The creatures 

 are merely the material on which evolutionary processes exert their 

 influence and on which they leave their marks and it is from a study 

 of these marks that we reconstruct their past history and experience. 



Clamator has existed in a less active, more "secluded," evolutionary 

 arena than some other genera of its family. Nonetheless, it has had a 

 long, continuous, and successful history, and in the course of this 

 great duration it has shown an early adaptation in tgg coloration to 

 a then new and fairly definite set of host species, and much later, in 

 its climax form, a partial escape from the overly restrictive results of 

 this rigid host specificity. In between these two important incidents 

 in its development, it has pursued a fairly even and relatively im- 

 eventf ul existence, although involving differentiation into four species, 

 each with considerable geographic shifting of stock. This brings out 

 the fact that, in studying a group of organisms, the concept of their 



