Generalization of a visual matching-to-sample rule was shown for the first time in a bottlenosed dolphin (Tursiops truncatus), normally considered an auditory specialist. The visual items used were all real-world objects. Some objects had acoustic names in an artificial acoustic language taught to the dolphin named Phoenix. Other objects were unnamed but familiar to Phoenix, and still others were objects entirely new to her experience. In Experiment 1 and 2, we demonstrated Phoenix's ability to match these objects, from among two alternative comparison objects, at levels of 87% correct responses or better, after 0-s delay. In Experiment 3, Phoenix's matches of familiar and of new objects were better than 94% correct through to delays of 30 s and were 73% correct after a delay of 80 s. In Experiment 4, performance was nearly equivalent for statically displayed and dynamically displayed sample objects. Over the four experiments, Phoenix matched 16 of 18 objects successfully on the first trial that they appeared as samples. From these and other recent Findings, it appears that bottlenosed dolphins are capable of carrying out both visualand auditory-based complex cognitive tasks approximately equally well, a finding at variance with earlier notions of sensory modality limitations in cognitive performance of animals.Animals may interact with their world through a variety of sensory' modes, yel il often appears that many cognitive capacities are modality limited. The concept of modality limitation, often called modality specificity, holds that advanced cognitive skills, or even simple ones, may be largely restricted to the dominant sensory modality of the species. For example, monkeys may solve visual hut not auditory tasks easily (D'Amato, 1973;D'Amato & Salmon, 1982;Thompson, 1981), whereas the reverse may hold for dolphins (Herman, 1980). These modality-related differences are not traceable to raw sensory limitations. Monkeys have welldeveloped hearing abilities (Fobes & King, 1982) and dolphins have a highly evolved visual system (Dawson, 1980; Herman, Peacock, Yunker, & Madsen, 1975).Recent work has begun to dispel or reshape some of the notions about modality specificity. D'Amato and Colombo (1985) and Colombo and D'Amato (1986) reported on the ability of capuchin monkeys (Cebiis apella) to learn auditory delayed matching-to-sample (DMTS) tasks, and similar find-
