Paris (AFP)

Frozen for eternity: the skull of a tiny bird, exceptionally well preserved in amber for 99 million years, was discovered in Burma, and could be the smallest dinosaur known to date, according to a study published Wednesday.

"I was literally blown away, I had never seen anything like it. It's wonderful!", Says paleontologist Jingmai O'Connor, lead author of the study published in the journal Nature, to AFP.

The specimen, called "oculudentavis khaungraae", was trapped in a piece of amber dating from the middle of the Mesozoic era (-251 million years to -65 million years). With a skull 7 mm in length, it rivals in size with the bee hummingbird, the smallest of the birds currently alive, making it the smallest known dinosaur of this era, according to Nature.

"Like all animals locked in amber, it is very well preserved. It looks like he died yesterday, with all his soft tissue trapped in this small window overlooking ancient times", comments Jingmai O ' Connor, from the Beijing Institute of Vertebrate Paleontology and Paleoanthropology.

Through the translucent medallion, we see a skull in profile dominated by a large eye cavity, suggesting an eye looking to the side, similar to that of a lizard. Using a CT scan, the researchers were able to highlight a jaw full of sharp teeth - a hundred in total.

- Small predator -

"It doesn't look like anything alive today, so we have to be imaginative to understand the meaning of its morphology. But its streamlined skull, multiple teeth and large eyes suggest that despite its small size, it was probably a predator that fed on insects, "says the paleontologist.

The tiny vertebrate, nicknamed "teenie weenie" in English ("all mini"), co-existed with long-necked dinosaurs, large flying reptiles such as pterosaurs, at a time when wildlife was very rich.

It was a little-known micro-fauna that only amber was able to preserve. How? 'Or' What ? "Imagine a swamp or a forest near the sea, with trees producing a large amount of resin, some pieces of which detach themselves by oozing along the trunks, capturing the fauna living on them," describes Jingmai O'Connor.

Without this fossilized resin, "we wouldn't know anything about these tiny organisms, which are much more difficult to find than the big ones," she said.

"When we think of dinosaurs, we think of these huge skeletons but currently, paleontology is completely transformed by the discoveries of small fossils thus preserved", continues the scientist.

In recent years, "Burmese amber has given rise to surprising discoveries," adds Roger Benson, a researcher in paleobiology, in a commentary published with the study.

Frogs, lizards, amonites ... "There are still a lot of specimens to study!" Rejoices Jingmai O'Connor.

"And I hope that within the next ten years, we will be able to develop techniques allowing access to the biochemistry of the soft tissues. There are certainly fragments of DNA preserved inside ... but there n "There will never be a scenario at + Jurassic Park +!", she reassures.

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