New research shows the American alligator has remained virtually untouched by major evolutionary change for at least 8 million years, and may be up to 6 million years older than previously thought. Few living vertebrate species have such a long duration in the fossil record with so little change.

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New research shows the American alligator has remained virtually untouched by major evolutionary change for at least 8 million years, and may be up to 6 million years older than previously thought. Few living vertebrate species have such a long duration in the fossil record with so little change.