The flying fish ( Exocoetidae ) is found in most of the world’s seas. This curious animal jumps out of the water and rises more than ten meters before returning to the depths of the ocean. For this reason, it is possible to imagine the amazement of the first Mediterranean sailors who encountered these particular fish. However, did you know that flying fish don’t actually know how to fly?
What are flying fish?
There are about 40 species of flying fish and all of them have long and wide fins on each side of their body. Likewise, it is possible to differentiate between two-winged flying fish (whose two large pectoral fins comprise most of their body) and four-winged flying fish, which have two large pelvic fins in addition to two smaller pectoral fins.
The length of these fish can vary, since they can measure between 15 and 50 centimeters. In addition, they begin to ‘fly’ approximately when they reach five centimeters in length, as biologist John Davenport maintains in a study published in the journal Reviews in Fish Biology and Fisheries . The researcher considers that this species developed the ability to ‘fly’ as a way to evade fast-swimming predators, such as dolphins.
On the other hand, the eyes of these fish (in particular the cornea) have evolved to allow them to see both underwater and in the air, as a 1967 study published by the journal Nature concludes. In addition, these fish feed mainly on crustaceans and smaller fish.
Flying fish don’t fly, they glide
Flying fish move so fast that, for decades, scientists did not know exactly whether the fish propelled themselves by moving their pectoral fins and flying like a bird or using a unique method of propulsion. In fact, it wasn’t until 1941 that researchers were able to take high-speed photographs of these fish. The images showed the flying fish leaping out of the water and gliding before propelling themselves through the air again.
In addition, this species swims towards the surface at a speed of one meter per second (that is, they swim 20 to 30 times their body length in one second), striking their tail energetically and holding their pectoral fins against their body. Finally, when they come out of the water they spread their fins and glide away.
