NO. 4 AVIAN GENUS CLAMATOR — FRIEDMANN I3 



morphism, and none of the instinctive eviction of nestmates by the 

 newly hatched young, so characteristic of some species of Cuctdus. 

 Also, compared with the latter genus, all four of the species of 

 Clamator are far more prone to deposit multiple eggs in individual 

 host nests, either multiple eggs by the same cuckoo or multiple use 

 of the same nest by several cuckoos. These differences suggest that 

 the refinements shown in Cucidus are evolutionary advances over 

 the basic cuculine stock and that Clamator is nearer to the original, 

 common ancestor in these matters. This lack of conformity or control 

 in ^gg deposition led Mountfort (1958, pp. 54-56) to conclude that 

 "... the parasitic behaviour of the Great Spotted Cuckoo is in many 

 respects more complicated than that of our familiar Cuckoo, in which 

 the single nestling merely evicts its foster-brothers from the nest . . ." 

 It seems truer to say that the "uncomplicated" behavior of Cucidus 

 canorus is a result of much adaptive evolution, whereas the "com- 

 plicated" picture in Clamator glandarius still retains much of the 

 simpler, less-developed features of the basic primitive parasitic cuckoo 

 that we may postulate as the remote source of both genera. In my 

 introductory statement I mention that the entire literature and think- 

 ing about cuckoos is overly dominated by Cuculus canorus. If specific 

 evidence were needed to demonstrate this. Mount fort's statement 

 about Clamator glandarius would be a case in point. 



All the species of Clamator have the habit, common to so many 

 parasitic cuckoos, of removing one or more of the host eggs from 

 the nests of their victims either before or after laying in them. 

 Occasionally this does not take place, and in some nests some of the 

 host eggs are dented (equivalent, in survival terms, to destroyed) 

 by the beak or the claws of the adult parasite. There are ample 

 observational data on this in three of the species — jacohinus, coro- 

 mandus, and glandarms. The lack of such records for levaillantii is 

 not significant. There is no need to repeat here these observations as 

 they are already on record in my earlier (1949a, 1956) accounts, 

 and in that of Stuart Baker (1942). Particular mention may be 

 made, however, of Mountfort's observations (Mountfort, 1958, pp. 

 54-56; Mountfort and Ferguson-Lees, 1961, pp. 98-99), one of the 

 few detailed recent contributions on this habit in C. glandarius. They 

 marked eggs with indelible ink so as to be able to identify them 

 individually on consecutive days; they found that when the hen 

 cuckoos laid they removed one and sometimes two of the magpie's 

 eggs. In no instance did they remove eggs laid by other great-spotted 

 cuckoos, which raises the question as to whether they could recognize 



