THE HONEY-GUIDES 69 



stores or on domestic hives) and no longer go about in the bush calling 

 to honey-guides, the birds no longer make any attempt to lead men to 

 bees' nests. They simply do not have the experience of associating 

 humans with bees, and hence there is nothing on which to base or 

 develop the associative memory necessary to cause them to make any 

 attempts to guide humans.^* Conversely, in those areas where they 

 do still gather wild honey, the natives, in trying to enlist the help of 

 honey-guides, use methods which make use of associative memory on 

 the birds' part by imitating the grunts of the ratel and by hitting on 

 trees to imitate the sound of chopping open bees' nests. 



Inasmuch as the present discussion involves memory on the birds' 

 part, it should be mentioned that Thorpe (1951, pp. 277-278) has 

 brought together data showing that some birds may remember indi- 

 viduals for over a year. He emphasizes that "where the learning con- 

 cerns types of food available only at a certain time of the year, of 

 situations linked with a particular phase of the breeding cycle, a 

 memory of less than 12 months' duration might be of very little 

 biological advantage." Associative memory is thus highly probable. 



However, while the above-mentioned imitative acts of the natives 

 serve to increase their chances of enlisting the aid of the birds, they 

 are not necessary, as frequently the birds come to men unsolicited 

 and then begin their guiding behavior. Allowing for the probability 

 of associative memory causing a proper response, we still have to 

 account for the birds beginning to entice their "followers" to a distant 

 place where bees are swarming. To assume that the honey-guides 

 chattered at their bees' nest associates at greater and greater distances 

 from the focus of feeding interest is in itself not a very great assump- 

 tion, and it would be about all that is needed. There is no reason for 

 assuming any rationalizing on the part of the birds, but to credit them 

 with the ability to recognize "useful" animals, such as ratels and 

 humans, is not too hazardous. Experiments have shown that many 

 birds distinguish predatory hawks from other large birds by their 

 silhouettes against the sky. Chapin points out to me that Buphagus 

 obviously distinguishes between various large mammals for it is 

 attracted mainly by rhinos, hippos, buffaloes, giraffes, large antelopes, 

 and wart hogs but relatively seldom by elephants, zebras, wildbeest, 

 and small antelopes. 



It requh-es no great assumptions to see how the honey-guide and 

 the ratel or other bee-predator originally came in contact with each 

 other. What does still pose a question is how did the bird come to 



" One may recall that in her discussion of conditioned actions, Nice (1943, p. 60) 

 concluded that the "activity is innate but its object is often learned," agreeing 

 with a similar conclusion reached by Lorenz (1935). 



