New species of bat-wing dinosaur discovered

The rare fossil find from China is the best preserved example yet of this very odd dinosaur group.

 

This illustration depicts Ambopteryx longibrachium, a newfound species of nonavian theropod dinosaur that had bat-like membrane wings. It lived in what's now China about 163 million years ago.

Illustration by Mr. Chung-Tat Cheung

By Michael Greshko

---

PUBLISHED May 8, 2019

Mais de 160 milhões de anos atrás, as florestas da China antiga eram o lar de um predador bizarro: um minúsculo dinossauro que deslizava de árvore em árvore com asas de couro parecidas com morcegos. O fóssil recém-descoberto, revelado hoje na revista Nature, é apenas o segundo dinossauro de penas encontrado com sinais de grandes membranas em suas asas. Ajustando, então, que o nome do gênero recém-atribuído ao animal é Ambopteryx: Latin para “ambas as asas”.

  "A coisa mais excitante, para mim, é que isso mostra que alguns dinossauros desenvolveram estruturas muito diferentes para se tornarem volantes", ou capaz de voar, diz o principal autor do estudo, Min Wang, paleontólogo do Instituto de Paleontologia e Paleontantropologia da China. .

 See Ambopteryx Fly Through an Ancient Forest

In this artist's reconstruction, the Jurassic dinosaur Ambopteryx longibrachium glides through the treetops. The feathered creature had large membraned wings like today's bats.

Video Courtesy Min Wang, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences

Ambopteryx is now the best known fossil of a scansoriopterygid (scan-soary-OP-teh-rigid), an oddball group of nonavian dinosaurs that includes Yi qi, the first dinosaur ever found with bat-like wings. That fossil find—announced in 2015 by study coauthor Xing Xu, the IVPP's deputy director—reshaped how scientists understood the evolution of flight.

“Before the discovery of Yi qi, every flying dinosaur we found, we tried to fit on one evolutionary lineage toward birds,” says study coauthor Jingmai O'Connor, an IVPP paleontologist who specializes in ancient birds. “Yi qi really just shattered that idea.” (O'Connor also helped describe the first bird fossil found with an egg inside.)

Today’sPopular Stories

Science & Innovation

New species of bat-wing dinosaur discovered

Alguns pesquisadores agora acham que o vôo surgiu pelo menos quatro vezes separadas dentro dos dinossauros, inclusive entre os scansoriopterygids. Mas o ceticismo saudável em torno de Yi qi permaneceu. O animal tem estranhos ossos em forma de bastão, chamados de elementos estiliformes que se projetam de seus pulsos, e os paleontologistas achavam que poderiam estar lá para ajudar a sustentar uma grande membrana lateral. Mas nenhum outro dinossauro, vivo ou morto, também tinha tal osso - até o Ambopteryx.

  O fóssil recém-descoberto não tem apenas elementos estiliformes, também preserva um filme acastanhado em uma asa - um material que se acredita ser traço da membrana da asa. Além disso, Ambopteryx possui penas fossilizadas e um pygostyle, um grupo de vértebras de cauda fundidas que ancora as penas da cauda em pássaros vivos.

A flying 'dinosaur squirrel'

A local farmer found the Ambopteryx fossil in 2017 outside a village near Lingyuan, a city in northeastern China's Liaoning Province. When the IVPP first acquired the fossil, researchers thought it might be an early bird, so Wang—an expert on the early evolution of birds—took the lead. But as preparators carefully removed excess rock, Wang realized that the animal wasn't a bird at all. (Find out more about birds, the dinosaurs that didn't die.)

Now fully exposed, the fossil preserves in detail how Ambopteryx made its living. In all likelihood, it was an opportunistic omnivore: Its stomach contains gizzard stones like those in today's plant-eating birds, but it also bears bone fragments, signs that the creature enjoyed a meaty snack soon before death. The adult animal weighed just a few hundred grams, give or take.

Researchers are still crunching the numbers on how well it could have flown—though at a minimum, it looks well-suited to gliding among trees. Its feet suggest that it evolved to perch on trees, but rather than acting like a songbird, the team thinks it may have behaved like today's flying squirrels and sugar gliders.

“It probably would have been climbing around in the trees—like a little, creepy-looking dinosaur squirrel—and then flying from branch to branch,” O'Connor says.

“If you were going to get a gliding arboreal theropod, it would be a really weird animal, and it would look pretty much like this,” says University of Southern California paleontologist Mike Habib, a biomechanics expert who is studying the flight of Yi qi.

Flying into the unknown

Scientists are keen to find more hints of soft tissue in Ambopteryx, which new imaging techniques could make easier. For instance, University of Hong Kong paleontologist Michael Pittman has used lasers to reveal soft-tissue traces in fossils of the feathered dinosaur Anchiornis.

And Pittman is no stranger to scansoriopterygids. At the 2018 meeting of the Society of Vertebrate Paleontology, Pittman's Ph.D. student Arindam Roy presented early results from the lab's laser scans of Yi qi. Wang and Pittman say they are talking to each other about doing a similar analysis of Ambopteryx.

To get clearer answers, paleontologists say the ideal would be to find an even better-preserved relative of Ambopteryx. That's a lot to ask for—but sites in China preserve feathered dinosaurs in mind-boggling detail. Perhaps an even more pristine bat-winged creature is waiting to be unearthed.

“We've gotten so used to great Chinese fossils, we start making really inappropriate asks, like, Well, why didn't you find one that's preserved perfectly in every detail and shows everything laid out?” Habib quips. “It's totally raised the bar of what a good fossil is.”