© 1974 by The Society for Integrative and Comparative Biology
Contrasts in Social Behavior between Central American Cichlid Fishes and Coral-reef Surgeon Fishes
Department of Zoology and Museum of Vertebrate Zoology, University of California Berkeley, California 94720
The social systems and related behavior of cichlid and surgeon fishes are compared in terms of (i) physical spacing, (ii) theoretical spacing (communication), (iii) castes, (iv) group composition, (v) open versus closed groups, and (vi) reproductive behavior.
Cichlids only recently invaded Central America. Despite the occurrence of about 100 species there, most are in one genus, Cichlasoma. Yet, they express a spectrum of feeding behavior, ranging from grazing herbivore through omnivore to predator, each of varying degrees of specialization. In contrast, their social behavior is remarkably conservative. There is a tendency for the generally found division of labor, with the female doing more of the direct caretaking of the eggs or fry and the male more of the defense, to lead toward polygyny. This is counterbalanced by the need for both parents to defend the fry. Communication is most accessible through a study of color patterns. While seemingly diverse, there is a common plan that entails the use of some or all of the same vertical bars and their central spots, and the appearance of yellow orange, red, or black ventrally.
The coral-reef community is one of the oldest in existence. Surgeon fishes are pantropical, especially in the Pacific Ocean, and have developed distinct generic groupings within a compact family of about 75 species. Most are herbivorous, with some more specialized than others. The species fall into guilds, within which there is broad overlap in diets. The social systems differ radically, both when breeding and when not, and can be understood as consequences of their strategies of obtaining food.
Wickler's classification of reproductive types within the Cichlidae is shown to be no advance over the previous dichotomy of substrate and mouthbreeding species. Poster coloration in surgeon fishes is apparently as important, or more, in extraspecific than intraspecific aggression, and poster-colored surgeon fishes show pronounced rapid color changes when fighting intraspecifically.