ARCHERFISH Living Water-Gun

newscientist.com

The Archerfish (Toxotes jaculatrix) deploys one very unusual hunting technique that works every single time, making it one of the deadliest hunter nature has to offer. The Archer Fish or spinner fish belongs to a family known as the Toxotidae. It has an unusual habit of making tasty snacks out of small animals (really small) and insects that live on land.
They inhabit brackish waters of mangroves and estuaries and are mostly found in Australia, India, Polynesia and Philippines.
As mentioned, they target land-based preys but the question is, how do they make it possible? They use water as their weapon. They shoot a jet of water from their mouth, with the finesse of a marksman, to hit insects and other prey above the water surface.
They even adjust for the gravitational pull that acts on the jet of water and manage to hit their prey with high precision.
They have highly developed eyesight that allows them to adjust for refraction of light that takes place at air and water boundary. The optical illusion caused by refraction will usually shift the position of the targeted prey. While hunting, the archerfish simply rotates its eyes so that the prey’s image falls in retina’s ventral temporal periphery. This allows them to pinpoint the exact location of the prey despite the optical shift at the air-water boundary.
In order to shoot the water efficiently, the archerfish will allow its lips to just break the water surface barrier. The force with which the archerfish will shoot the stream of water will also depend on the size of the prey and the force with which they hold on to the tree branches and shoots. The prey is never big and is almost always limited to small bugs and small lizards.
They use this same technique underwaterr to hunt for snacks hiding under the sand, leaves and other debris.
DESIGN OR RANDOM EVOLUTION?
References:
video.nationalgeographic.com, factslegend.com, newscientist.com, Wikipedia.com