24 U.S. NATIONAL MUSEUM BULLETIN 22 3 



in their buccal patterns. As Hoesch pointed out (1939), if the 

 Viduine species were as specifically adapted in tliis character as was 

 implied, this adaptation would have come about only if each species 

 of Vidua were confined to a single host species, to which the pattern 

 adaptively evolved. In addition to pointing out the improbability 

 of such a development, Hoesch indicated that localities are known 

 where viduines occur and maintain themselves without their supposed 

 correspondingly patterned host species. Hoesch also reported that 

 the paradise widow bird, which is parasitic chiefly on pytilias, does 

 not show any close correspondence with its host in the character of 

 nestling mouth markings. 



If the buccal decorations were acquired as an adaptation to brood 

 parasitism, they would have selective value, but for this consequence 

 there is as yet no real evidence. The resemblance in the mouth 

 markings of the young viduines and of then* frequent estrildine hosts 

 might be of some advantage to the parasites. Striking diflfereuces 

 in this respect might be enough to interfere with the nccessar}^ atten- 

 tive behavior of the fosterers. 



According to Lorenz (1935), the buccal colors and patterns of 

 3'oung parasitic cuckoos of those species that usually evict their 

 nest mates and thus get the undivided attention of the foster parents 

 are not very similar to the mouths of the hosts' j-^oung, whereas in 

 those species of cuckoos that grow up together with their nest mates 

 (e.g., Clamator glandarius^^) there is general similarity in pattern 

 and coloration revealed by the gaping mouths of the two kinds of 

 nestlings. Even in these species, however, it is possible and indeed 

 has been recorded that the young parasite can grow up with a nest 

 mate of quite divergent mouth pattern without evoking any critically 

 diiferent parental care. Fm-thermore, in the viduines, if one considers 

 the semidarloiess in which the young of the parasite and of the host 

 grow up together, it is difSult to see the need for a close correspondence. 



Recently in discussing the mouth pattern of one of the estrildines, 

 the bronze mannikin, Lonchura cucullata,^^ Morris (1957, p. 199) 

 rightly concluded that " taxonomically these markings arc conserva- 

 tive characters and are valuble aids to understanding the evolution of 

 thegroup." Delacour (1943, pp. 70-72) considered the mouth markings 

 to be of considerable taxonomic significance at the group, or tribal 

 level. He based his conclusion on the observation that all waxbills 

 and grassfinches have spots while all mannikins have semichcular, 

 horseshoe-shaped lines. As Morris (1958, pp. 397-398) pointed out, 



3» Cucuius glandarius Linnaeus, Systema naturae, ed. 10, vol. 1, 1758, p. Ill (north Africa and southern 

 Europe). 

 »• Spermestes cucullatus Swainson, Birds of western Africa, vol. 1, 1873, p. 201 (Senegal). 





