The unicorn fish of the order Pufferfish Monacanthus tuckeri has the ability to become invisible.
This small fish lives in the shallow waters of the Caribbean Sea. Justine Allen of Brown University was amazed at how quickly the fish managed to camouflage itself. In two seconds, she manages to change the color of her body and merge with the horny corals, which she swims past.
Ellen and her team managed to film the disappearance process on Little Cayman Island in the Caribbean. The researchers also studied the surface of the fish's body in the laboratory to understand how it masquerades as its environment.
Monacanthus tuckeri changes color to create "fake outlines". For example, a dark streak may appear on her skin, which visually creates a new body shape and the real contours go unnoticed.
How does a new pattern appear? Fish collect all the information about where they are. The brain then sends signals to the pigment-containing skin cells. Depending on the signal, the pigment can concentrate in the center of the cells in order to color a smaller area, or, conversely, fill the cell as a whole.
There are also small bumps on the skin of fish called skin flaps. They make the contours of the body less smooth and help the fish camouflage themselves as coral polyps, algae or sand lumps. This misleads not only predators but experienced researchers as well.
Daria Zhelnina
