Until Now
BiologyGeology

The Yanliao Biota

Chinese lake deposits preserve the oldest feathered dinosaurs and the earliest placental-line mammals.

When
Known to
± 1 million years
Era
Jurassic, Mesozoic

The Yanliao beds of northeastern China, dated with high precision to around 161 to 160 million years ago, yield feathered dinosaurs, transitional pterosaurs, and the earliest eutherian and multituberculate mammals — all with soft tissue preserved. It is the single most informative window onto Middle Jurassic terrestrial life, and much of what is known about the origin of feathers comes from it.

Just before

Just after