Microraptor

About Microraptor

Characteristics of Microraptor

Microraptor is a small dinosaur of the Dromaeosauridae family that lived during the Early Cretaceous (about 125 to 120 million years ago). It was only about the size of a crow or hawk, and was lightweight, weighing about 0.3 to 1.5 kilograms.

Its most prominent feature is that it possessed long, well-developed flight feathers (remiges) not only on its forelimbs but also on its hindlimbs.

Studies examining fossilized pigments under electron microscopes have revealed that Microraptor's feathers were not simply black, but had an "iridescent structural color" that shone blue or purple depending on the angle of light. This beautiful plumage, similar to modern crows or starlings, is thought to have also been used for visual display to others of its kind.

Furthermore, studies analyzing the size of its eye bones (sclerotic rings) suggest that Microraptor was highly likely nocturnal, hunting in the dark of night or in dimly lit forests. Its glossy black feathers probably functioned as effective camouflage in the nocturnal forest.

The Last Supper: Diet Revealed by Fossils

It was once thought that they "lived in trees and caught insects and small birds," but several fossils have been found with intact stomach contents, revealing the true diet of Microraptor.

• From the stomach of one specimen, a primitive bird swallowed almost whole was found.
• Fish bones were discovered in another specimen.
• Lizard bones were found in yet another specimen.
• In a 2022 study, the foot of a small mammal was found intact near the stomach of another fossil. This mammal is thought to have been a ground-dweller that did not climb trees.

These discoveries show that Microraptor was a highly adaptable, opportunistic predator that hunted a wide variety of prey across different environments, from the treetops (birds) to the water's edge (fish) and the ground (lizards and mammals).

Flight and Terrestrial Mobility (Four Wings and Flapping Running)

The distinguishing feature of Microraptor is that it had flight feathers on its hindlimbs as well as its forelimbs. How it used these "four wings" to fly has been a long-standing mystery.

Initially, a theory was proposed that it "flew with its hindlegs spread out horizontally (X-wing model)," but it is now known that dinosaur skeletal anatomy makes such a posture difficult. Today, the leading theory is the "biplane model," where the hindlimbs were tucked in a Z-shape and positioned below the forelimb wings, allowing it to glide in a swooping motion between trees. The long tail feathers acted as a stabilizer during flight.

Furthermore, studies of the footprints of a tiny dinosaur found in South Korea (Dromaeosauriformipes rarus) revealed new facts. The stride length was unusually wide compared to the foot size, indicating a speed that could not be explained by leg strength alone.

This is thought to be evidence that Microraptors engaged in "Wing-Assisted Incline Running" (WAIR), vigorously flapping their wings to lift their bodies while running up slopes or across the ground. They could not only glide from trees but also move nimbly on the ground using the power of their wings.

The Truth About the Wings Revealed by Latest Technology

In recent paleontology, a technique called Laser-Stimulated Fluorescence (LSF) is used, shining a special laser on fossils to reveal traces invisible to the naked eye.

This technology confirmed the presence of strong muscles necessary for gliding and flapping, as well as an aerodynamic skin membrane (propatagium) around Microraptor's bones.
Furthermore, the fine connections of the feathers (barbs) emerged clearly, proving that their feathers were designed to trap air and generate lift, serving as true "wings for flight."

Gracing the Cover of "National Geographic"

What made Microraptor famous overnight was its appearance on the cover of the globally renowned magazine "National Geographic" in 1999.
The fossil smuggled out of China was named "Archaeoraptor" and was heavily publicized as the definitive new species bridging the gap between birds and dinosaurs. However, it was later exposed as a forged fossil (a chimera specimen) made by artificially attaching the tail of an unknown dinosaur to the body of a bird.

Subsequently, a Chinese research team discovered the true owner of this "tail" section and officially described it as "Microraptor" in 2000.
Incidentally, using the laser technology (LSF) mentioned earlier allows researchers to see differences in fossil composition at a glance, making it much easier to detect such forged fossils today.

Microraptor Stamp and Fossil Gallery