Half-billion-year-old microscopic animal fossils found in Greenland. Among the fossils, researchers discovered the preserved hook-like teeth of priapulid worms, which the predators used to burrow into the mud in search of prey.

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Half-billion-year-old microscopic animal fossils found in Greenland. Among the fossils, researchers discovered the preserved hook-like teeth of priapulid worms, which the predators used to burrow into the mud in search of prey.