Ancient birds fly with 4 wings

The oldest bird known to humans has feathers on their feet, allowing it to use these legs as an extra pair of wings, a new study reveals.

The discovery, published in Paleobiology , supports the theory that ancient birds learn to glide and 'parachute' from trees before making real flights.

A new study found archeopteryx has feathers flying in the back limbs, which play an important role for flight behavior. (Photo: LiveScience)

"The article has provided some of the strongest evidence that birds are descendants of people who glide and throw from trees down, similar to flying squirrels," study author Nick Longrich, a study. PhD student at University of Calgary in Canada.

Archeopteryx is a crow-sized creature that lived about 150 million years ago and looks like a transition between birds and dinosaurs. It has wings and collarbones like birds but has reptilian features like long bones with tails, claws and teeth.

When the Archeopteryx fossil was first found in 1861, it caused a stir in the scientific world because it was a transitional animal that English naturalist Charles Darwin pointed out in his evolutionary doctrine of only a few. years earlier.

In 1877, the second Archeopteryx specimen was found in Germany, showing a strange feature: long hairs on its hind legs. In the following century, these feathers were ignored by most scientists, considering it only as "fringe" fur - the fur that has no role in the animal's flight.

An Archeopteryx bird fossil (Photo: LiveScience)

But when digging in 2002, archaeologists began to find four-wing dinosaurs in China with feathers on the hind legs playing an important role for gliding and even flying. Before these new findings, Longrich decided it was time to reconsider Archeopteryx.

Longrich examined the feathers on the hind legs of five Archeopteryx fossils and found that these feathers have the characteristics of typical flying feathers in modern birds, such as curved stalks, self-overlapping patterns. and asymmetry (with parallel rows of fluff makes half of the hairs look longer than the other half).

Next, Longrich used standard mathematical models for flight to calculate how an extra pair of wings would affect Archeopteryx's flight. He found that the hair on the hind leg allowed Archeopteryx to slow down and change direction more suddenly.

This powerful turn-around ability will enhance the animal's effectiveness when chasing prey, when hiding enemies or flying through dense branches. Meanwhile, the ability to slow down means Archeopteryx has more time to avoid obstacles and make safer landing.

Longrich speculated that hindlimb feathers may have played another role in addition to flying. Like in pigeons, gulls and modern vultures, Archeopteryx's hindquarters can be brakes, stabilizers, control surfaces or flapping wings.

T. An