Scuba divers use special footwear to them swim better. what is the inspiration behind this design?

Scuba divers use special footwear called fins or flippers to help them swim better. The inspiration behind the design of this special footwear is from the fins of the fishes and the webbed feet of frogs and aquatic birds like duck ,swan etc.

Explanation

Scuba divers use special footwear called swim fins or flippers (fin like accessories ) which helps them to move swiftly through water. Swim fins are usually made up of rubber, carbon fiber, plastic etc. Fins of the fishes and webbed feet of aquatic birds and frogs assist them to swim swiftly in water by pushing the water backwards. In a similar way,  divers wearing fins can move in different directions by pushing water .  Fins allows them to swim easily and thus reduce the effort of the muscles while swimming.  To overcome the resistance of water caused by the diving equipment, divers need large and wide fins  which have more surface area  to push the water backwards. But it should be short enough to allow  movements through water.

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