There are more than 28000 predatory fishes in the world and each one has its own hunting strategies. However there are some predatory fishes whose hunting prowess can shame the best terrestrial hunters.
One such fish Toxotes which is better known as Archer Fish can turn their mouths into squirt guns and a single blast can literally sweep the prey off their feet and land them into the hungry mouth of the fish. Peggy Gerullis and Stefan Schuster from the University of Bayreuth studied how Archer fish can become such accurate hunters by regulating the jets of water. The paper was published in the journal Current Biology
It is another finest example of how evolution helps to refine and improve tools to obtain food. The Archer fish have evolved special organs which are used for shooting the jet of water. Earlier research had revealed that by positioning the tongue along the roof of the mouth, the fish is able to create a gun barrel like structure. The opening, closing and squeezing of the gills ejects the water to shoot out at the intended target. This is a unique feet because the fish would have to make corrections to take into account the refraction of light when it moves from air into water.
Gerullis and Schuster taught nine archer fish (T. jaculatrix) to shoot water jets at targets. These targets were placed 20, 40, and 60 centimeters away. The process of the shooting of water jet was filmed by a high speed camera. What the researchers discovered was incredible; the water doesn’t hit the insect in a steady stream. It strengthens just before it gets to the prey, delivering a powerful thump.
For targets which are farther away, Archer Fish opens its mouth slowly and use more volume of water than when aiming at closer targets. Archer fish can thus regulate the stream to make a more successful kill.