Question

How different are the swimming strategies used by osteichthyes and chondrichthyes? Why do sharks need to move their body to swim while bony fish do not?

Answer 1

Answer) Different Swimming strategies used by Osteichthyes and Chondrichthyes are accounted to their different anatomy and body organs. Bony fishes can swim easily as they possess the swim bladders which help them gain buoyancy during swimming. these bladders can be filled with gases so that fish body attains neutral buoyancy. Sharks do no possess such organs and they rely on their skeleton of light cartilage. additionally, dermal denticles over their skin aid the sharks in minimizing the drag and maximizing the efficiency of swimming.

though, bony fishes possess the swim bladder and fins, which help them to swim even without moving their body. sharks do not possess swim bladder and they need to continuously move their body in order to swim. in short, swim bladder allows bony fishes to swim even without moving their body.