May 9, 2019

Scientists have discovered a tiny bat-like dinosaur

A 3-D reconstruction of Ambopteryx longibrachium. Image: Min Wang, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences

Scientists have found new evidence that bat-like dinosaurs once fluttered through the skies.

What's new: A tiny dinosaur with membranous, bat-like wings lived during the Upper Jurassic period, according to a study in Nature on Wednesday. A fossil of the species — named Ambopteryx longibrachium — was found in northeastern China's Liaoning Province and dated to around 163 million years ago, bolstering the conclusions of a 2015 study detailing a less well-preserved but similar fossil finding called Yi qi. The specimen in the new study, by Min Wang and colleagues from the Chinese Academy of Sciences, is superbly preserved — researchers were even able to glean information from its stomach contents.

Details: The new species likely weighed only about 200 grams and could have fit in your hand, paleontologist and study author Jingmai O’Connor, told Science. “It would have been this tiny, bizarre-looking, buck-toothed thing like nothing alive today.”

  • It also had feathers, along with bat-like, membrane wings supported by a long, pointed wrist bone, a type of structure that has been found in non-dinosaur flying vertebrates such as bats and pterosaurs.
  • Scientists aren't yet sure exactly how this winged dinosaur flew.
  • Ambopteryx longibrachium likely points to changes in wing structure around the time that scansoriopterygids, a family of climbing and gliding dinosaurs, split with bird lineages.
  • In other words, it may represent an evolutionary dead-end that consisted of bat-like dinosaurs, and there may be other flying dinos that we don't yet know about.

The bottom line: The study, along with other research, puts forward the idea that membranous wings and elongated forelimbs in scansoriopterygids were likely short-lived evolutionary experiments with flight, since feathered wings and the birds we know of today came to predominate later.

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