Until Now
Biology

Dinosaurs have feathers

Feathers evolve long before flight, on animals with no prospect of leaving the ground.

When
Known to
± 5 million years
Era
Jurassic, Mesozoic

Yanliao fossils preserve filamentous and vaned feathers on small theropods that plainly could not fly. Feathers therefore originated for insulation, display or brooding, and were only later co-opted for flight — the same pattern seen with limbs evolving in water. Feathers may be ancestral to a much wider group of dinosaurs than just the bird line.

Just before

Just after