why does my betta fish keep going behind the filterRegarding competitive behaviour, other than a few examples using biomimetic artefacts to rouse intraspecific competitive response in the dart poison frog, Epipedobates femoralis Barbour, and in swamp sparrows, Melospiza georgiana Latham35, 36, as well as anxiety associated behaviour in zebrafish when uncovered to predator mimicking robots37, 38, agonistic interactions are almost unexplored by the biomimetic method. Aggressive behaviour is widespread across the animal kingdom because it has a key role in buying and protecting restricted resources39,40,41,42. Game theory predicts that evolutionarily stable concepts for conflicts occurring among conspecifics, may contain stereotyped contests featured by the ritualized exchange of agonistic cues43, 44. In this study, we investigated biomimetic aggressive interactions involving the Siamese combating fish, Betta splendens Regan Perciformes: Osphronemidae, and a conspecific mimicking robotic fish in an open loop agonistic interaction. Siamese fighting fishes have territorial males acting highly stereotyped and full of life competitive shows against conspecific males45,46,47. On this basis, we chose this species as an animal model to explore the interactive outcomes of a robot inducing aggression in the aquatic atmosphere.