The first land vertebrates did not undergo metamorphosis

Animals
The first land vertebrates did not undergo metamorphosis

Ancient fossils reveal that the ancestors of all modern mammals and reptiles were born as miniature adults rather than tadpole-like larvae.

For decades, biology textbooks have taught that the first vertebrates to walk on land transitioned from water much like modern frogs. This theory suggested that early tetrapods began life as aquatic larvae with external gills before undergoing a radical body reorganization to survive on land. However, a mislabeled fossil found in a garage collection has overturned this long-held assumption.

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