Early land animals skipped the tadpole phase

Researchers analyzing rare, microscopic fossils of baby tetrapods discovered that the first animals to conquer the land completely skipped the tadpole phase. The finding means that the first land-dwelling vertebrates were less like modern amphibians than had previously been thought, upending scientists' understanding of how animals conquered the land. Comparative analysis across multiple early tetrapod lineages shows larval stages more similar to fish or amniotes than modern amphibians, challenging the view that amphibian-like metamorphosis mediated the water-to-land transition.

Source: Ars Technica | 2026-06-23