Trying to mimic the almost impenetrable skin of the "dragon fish" are scientists including an Indian origin. They are trying to develop a body armour for military personnel that could replace the heavy Kevlar armour currently used.
Each of the scales that cover the long body of Polypterus senegalus is made up of multiple layers. When the fish is bitten, each layer cracks in a different pattern so that the scale stays intact as a whole.
Now researchers have found how the different types of scales work - as a series of joints between "pegs" and "sockets", allowing the fish to bend as it swims, according to the New Scientist.
This combination of flexibility and strength is perfect for human armour, said Swati Varshney of the Massachusetts Institute of Technology, while speaking at the Society for Integrative and Comparative Biology meeting in San Francisco earlier this month.
Varshney and her team performed X-ray scans of scales, reconstructed the shapes and then worked out how they slotted together.
Scales near the flexible parts of the fish, such as the tail, are small and allow the fish to bend. Those on the side, protecting the internal organs, are larger and more rigid. Their joints fit together tightly so that each peg reinforces the next scale rather than allowing it to flex.
The researchers created computer models of the different scale types and blew them up to 10 times their original size. Using a 3D printer, they printed a sheet of 144 interlocking scales out of a rigid material.
The team is planning to eventually develop a full suit of fish-scale body armour that would be rigid and strong across the torso and more flexible towards the joints.