Previous studies have shown that many teleost fish species form social aggregations. In addition to the adaptive significance of the aggregations of fishes, or shoals, factors that affect shoal mate choice have been well researched. The conventional method for investigating shoal mate choice was to observe the spontaneous preference between two potential shoal mates by using a side-by-side presentation, and still or videotaped images were widely used in previous studies. Visual cues, such as sex, body coloration, body size, and motion, play an important role in inducing shoaling behavior. However, few studies have systematically manipulated both morphological and motion cues. Information on motion cannot be obtained from still image. In addition, researchers have difficulty in finely controlling and manipulating a variety of parameters of videotaped images of moving fish. Therefore, we constructed 3DCG animations of medaka on the basis of the tracking coordinate data of real medaka. Medaka were used for the current study because they had been known to have a high visual acuity and to exhibit a strong tendency to form shoals. 3DCG animations enabled us to depict medaka faithfully and examine the relative contributions of morphological and motion cues to the induction of shoaling behavior. The experimental results will be presented in the conference.