The fossilized discovery in China of modern birds' oldest relative puts their origin six million years earlier than previously thought.

The fossils of the oldest known ancestor of modern birds, found by paleontologists in China, has prompted scientists to rethink the date of the first appearance of the Ornithuromorpha clade of birds, which includes all modern species.

As a result of the discovery, the date has jumped back by around six million years to 130.7 million years ago, a team led by researchers from the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing announced on Tuesday.

According to the findings, published in the journal Nature Communications, the animal, named Archaeornithura meemannae, was a wading bird, which used its long legs like today's cranes and herons to look for food on the shores of a lake.

The bird had feathers and was able to fly, though its short wings mean it probably spent most of its time on land.

The two fossils were discovered in the Huajiying Formation in northwestern China, the second oldest avian-bearing deposits in the world after the Upper Jurassic Solnhofen Limestones that preserve the Archaeopteryx in Germany.

The Archaeopteryx, though it has no living descendants, is considered to be the first bird, an intermediate between the birds we see today and predatory dinosaurs; it lived around 150 million years ago.