How does the anal fin propulsion system allow knifefish to change direction compared to typical caudal fin propulsion?

Answer

They can swim both forward and backward, instantly backtracking without turning their body.

The long anal fin allows them to swim backward instantly when encountering an obstruction or prey, contrasting with typical teleost fish that require a complete body turn using the caudal fin to change direction effectively.

How does the anal fin propulsion system allow knifefish to change direction compared to typical caudal fin propulsion?
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