Archer fish

29november2014
Source: scientias.nl, photo by Chrumps
The archer fish literally shoots its prey down. With great precision, it can fire a jet of water to shoot down its prey in the air. Adult archer fish seldom miss their targets.
Archer fish (Toxotes) can shoot their prey out of the air from a distance of up to two metres above the water’s surface. This prey could be an insect, a spider or even a small lizard. Scientists at the university of Bayreuth (Germany) conducted research on the way in which the archer fish takes down its prey. In their experiments, the prey (an object like a marble) was placed at various distances from the fish. Every time an archer fish fired, the stream of water it shot came apart just before hitting its target, turning into many blobs of water. The largest of these water blobs landed just short of the prey. The fish achieves this precise aim by increasing or decreasing the size of its mouth opening. That’s all it does, shoot water; otherwise it remains perfectly still.

The researcher suspects that the craft of the archer fish evolved in the same way as humans’ ability to throw: many neurons are required to take down our prey at a large distance with a spear.
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