The archer fish adjusts its jet before it hits its target

The archer fish can drop a prey out of the water by throwing it from the surface. The difficulty goes beyond the aim. A sufficient amount of water should strike at the right time, instead of dispersing before reaching the target.

In a study published in 2014, researchers trained fish to shoot at targets placed at different distances. They observed that the maximum concentration of water at the front of the jet occurred just before impact. Shots aimed at the most distant targets kept their cohesion longer: the jet was not simply identical with each attempt.

The animals adjusted the dynamics of opening and closing the mouth. This modulation changed the formation of the projectile during its displacement. No need to assign them a conscious calculation of fluid mechanics: the experience reveals a behavioral mastery. A seemingly simple attack depends on a setting producing its effects after the departure of the jet.