What is the primary mechanism of camouflage exhibited by the harbour porpoise's coloration pattern?

Answer

Countershading

The harbour porpoise displays classic countershading, meaning its dorsal area is dark grey or brown to blend with the depths when viewed from above, while its ventral area is distinctly whiter to blend with bright surface light when viewed from below.

What is the primary mechanism of camouflage exhibited by the harbour porpoise's coloration pattern?
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