What functional advantage might pronounced keels provide in the shared aquatic/semi-aquatic niche?

Answer

Increased traction on slippery substrates like wet mud

Pronounced keels can provide a functional advantage by increasing surface area, which assists in traction on slippery substrates such as wet mud or vegetation, and potentially aids in movement through water.

What functional advantage might pronounced keels provide in the shared aquatic/semi-aquatic niche?
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