What adaptation, fundamental to all penguins, helps them grip slippery prey like fish once captured underwater?

Answer

Backward-pointing spines called papillae

Penguins have specialized tongues and palates covered in backward-pointing spines, called papillae, which function to grip slippery prey during the ascent to the surface.

What adaptation, fundamental to all penguins, helps them grip slippery prey like fish once captured underwater?
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