Fig. 1

Novel visual familiarization system with separation condition (a) Time-course of the female mating receptivity test. A case of far focal male is shown. See the Materials and Methods for details. (b-d) Separation conditions for the female mating receptivity test in dyadic relationships. Fish were randomly picked from two communal tanks each containing four males and four females and the same males were used several times in the three conditions. (b) “Near: WT, Wall: opaque” The female couldn’t see the male in the near zone and mated with it in the next morning. (c) “Near: WT, Wall: transparent” The female could see the male in the near zone from a close proximity and mated with it in the next morning. (d) “Far: WT, Wall: transparent” The female could see the male in the near zone from some distance and mated with it in the next morning. (e) Visual familiarization enhanced female receptivity even if the male was located in the far zone. Mean ± SEM. ***P < 0.0001