no. 7 



FLOCKS OF NEOTROPICAL BIRDS — MOYNIHAN 



IO3 



attractive or, at least, less irritating and/or frightening to individuals 

 of most of the species of the montane bush alliances than an other- 

 wise similar bird of different colors. 



Diagram 3. — The special interspecific preferences of the most common species 

 of the higher-altitude montane bush alliances revealed by predominantly "friendly" 

 following and/or joining reactions. Organized in the same way as diagrams 

 1 and 2. 



The species are identified by initials. RS = red-faced spinetail. CR = col- 

 lared redstart. BCT = brown-capped bush-tanager. ST = sooty-capped bush- 

 tanager. B W = black-cheeked warbler. YF = yellow-thighed finch. YB = yel- 

 low-throated bush-finch. 



Perhaps the best evidence that the similar coloring of most of the 

 species in mixed montane bush flocks is a significant factor tending 

 to stimulate the formation and maintain the cohesion of such flocks 

 is provided by the behavior and social relations of certain other species 

 that occur in the same areas but are colored very differently. 



