THE HONEY-GUIDES 65 



is more of a flycatcher in its feeding habits than is I. indicator, although 

 the latter also catches some of its insect food in that manner. While 

 Melignothes and Pseudofringilla and Melignomon all still eat wax 

 regularly, it seems likely that their evolutionary trend is in the direc- 

 tion of less dependence on bee comb as a primary food source. This 

 condition has actually come to pass in the case of Prodotiscus, the 

 end result of the Melignomon line, to the extent that neither of its 

 included species any longer eats bee comb and its various inclusions 

 but feeds on scale insects very largely. This, in turn, suggests that 

 the primordial honey-guide stock may have been differentiated early 

 by its wax-eating proclivities from the line that produced the barbets. 

 This, again, has the theoretical advantage of providing an antiquity 

 for the wax-eating habit sufficiently great to have allowed for the 

 development of so complex a behavior pattern as guiding, a habit 

 which is obviously based on, or at least developed within the limits 

 set up by, an antecedent cerophagous tendency. 



If the basic honey-guide stock attempted to open hives, as seems 

 not improbable (and they are the one section of the family even 

 partly able to do so), they might have developed a symbiotic rela- 

 tionship with other bee predators (ratel, baboon, etc.), while the other 

 groups of the family with still poorer hive-opening equipment (smaller, 

 weaker bills) seldom or never made any such attempt themselves but 

 were merely involved, in an opportunistic sense, in the results of 

 these predator's raids. In other words, they were, if anything, 

 followers and not guiders— and followers only in the loose sense that 

 jackals and vultures are followers of carnivorous predators such as 

 lions and leopards. This seems to be reflected in the apparent absence 

 of guiding in these species of honey-guides. Thus, it seems not 

 unlikely that once the evolutionary trends towards less dependence 

 on bee comb and reduction in bill size set in, in the past history of 

 the Indicatoridae, there was no further incentive for an evolutionary 

 dispersal of the guiding habit into the then newer, formative groups. 

 It would appear, then, that guiding is not a recent development in 

 the honey-guides but an old, yet sharply restricted trait confined to 

 a single branch of the family. 



That the honey-guide, or, more specifically, the greater honey-guide, 

 had a prehuman associate in its guiding behavior has now been demon- 

 strated beyond doubt. This was an important point to establish, 

 and it was for this reason that I went to so much effort to gather 

 evidence on the ratel and other possible collaborators of the guiding 

 bird and to record these data in detail. And yet, even with these 

 prehuman associates, guiding apparently was never the sole or even 

 the basic method of food-getting either for the bu-d or for its symbionts. 

 The fact that many species of honey-guides do not guide (as far as 



