anyFish: an open-source software to generate animated fish models for behavioural studies

Problem: Using an experimental approach to study behaviours based on visual signals is severely limited due to the difficulty of combining realistic models (e.g. live fish) with the manipulation of signals in isolation. Solution: Computer animations allow the manipulation of a single cue while maintaining the rest of the behavioural phenotype of a realistic three-dimensional (3D) model. Software: We introduce the open-source software anyFish for the creation of 3D-animated fish. Both the animated model and its behaviour can be modified by the end-user to suit specific needs. Applications: Computer-animated fish facilitate the identification of factors influencing behaviours based on visual cues, and ultimately the way they both drive and respond to selection. For our research, we vary nuptial colour and size and shape of animated male stickleback to quantify female choice for these characters. The software has many other applications, as other fish species can be animated and characters like swimming speed and direction can be manipulated as well.