Scientists have found fossils in China of the earliest known birds with well-preserved plumage and features associated with both flight and wading.
Archaeornithura meemannae lived about 130.7 million years ago, five to six million years before the previous oldest-known bird specimens.
The two well-preserved fossils, announced in the journal Nature Communications, are the oldest known records of Ornithuromorpha, the same evolutionary branch which gave rise to all bird species now living.
Fossilised bird specimens from the Mesozoic era are rare with little being known about the early evolutionary history of the ancestors of modern birds.
Min Wang of the Chinese Academy of Science and colleagues describe this new species, found in the Sichakou basin in Hebei, as having a near-completely preserved plumage with anatomical features characteristic of an aerodynamic lifestyle and manoeuvrability during flight.
The absence of feathers on the upper leg is also indicative of a wading lifestyle, consistent with other fossil bird species found in similar deposits.