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Baby dinosaur fossil revealed to be an entirely new species

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After 25 years, we finally have a name for this mysterious fossilized fetus — and it’s a cool one

Beibeilong incubates its eggs
Beibeilong incubates its eggs.
Illustration by Zhao Chuang

A mysterious 90-million-year-old dinosaur fetus has finally been identified as an entirely new species, reports a new study published 25 years after the dino’s discovery. The paper closes the cold case by giving the fossilized fetus an official name: Beibeilong sinensis, which means “baby dragon from China.”

Since it was first unearthed, the little fossil has crossed from China to the US and back again. It was originally excavated from a field in Henan, China, in 1992 and sold to fossil dealer Charles Magovern in 1993. At his workshop in Colorado, Magovern chipped away at the stone and discovered between six and eight giant, crushed oblong eggs inside. At 2AM one morning, after clearing away the surrounding rock, Magovern uncovered what he thought was a leg bone. It turned out to be part of a 15-inch fossilized fetus, curled up atop the eggs. The little dino had probably been squished out of its egg before it hatched.

Featured in a 1996 National Geographic cover story, the fetal dinosaur was nicknamed Baby Louie in honor of the photographer who snapped its portrait. But Baby Louie’s genus, species, and genealogy were officially a mystery until today, with its comprehensive description published in the journal Nature Communications.

The fossilized skeleton of Baby Louie, now known as Beibeilong sinensis, is curled up on top of the dark gray eggshells.
Photo by Darla Zelenitsky

The authors write in the paper that Baby Louie’s export from China had been illegal. So, the scientists — led by Hanyong Pu at the Henan Geological Museum in China and paleontologist Darla Zelenitsky at the University of Calgary — waited until the fossil had been returned to China to publish their findings.

When Zelenitsky first saw the eggs preserved with Baby Louie in the mid-1990s, she thought they looked like eggs from a type of dinosaur called an oviraptorosaur. She’d seen similar ones before. Around the same time, Pete Makovicky, a paleontologist with the Field Museum of Natural History in Chicago who was not an author on the study, noticed the toothless lower jawbone resembled one from another oviraptorosaur species. The problem was that ID didn’t make a lot of sense to either of them.

Oviraptorosaurs are a birdlike dino in the same broad category as the Tyrannosaurus rex. They roamed the Earth between 130 and 65 million years ago on long, stilt-like legs. Instead of teeth, they tore at their food with beaks that jutted out of short, crested skulls. A short tail poked out from their rears, fanning out in a spray of feathers.

“They would look like some kind of crazy turkey on steroids,” Makovicky says. “They’re some of the more bizarre-looking dinosaurs.”

This illustration depicts how the eggs and the fetal fossil were preserved in the chunk of stone.
Illustration by Zhao Chuang

The problem was, all the oviraptorosaur fossils that had been found so far were much too small to have laid eggs as large as the ones found with Baby Louie. The crushed eggshells had once been elongated and tubular. Intact, they probably resembled giant zucchinis left on the vine for too long — in shape and size, although likely not color. They weighed around 11 pounds and measured in at up to 18 inches long and six inches across. “So these eggs were huge, indicating that the adult was huge as well,” Zelenitsky says. “But the thing is, at that time, all the known oviraptorosaur species were small bodied.”

The breakthrough came in 2007 with the discovery of a giant oviraptorosaur in north central China. Called Gigantoraptor, it stretched 26 feet in length and 16 feet tall. The discovery told Zelenitsky and her colleagues that they were on the right track: “It was like, you know what, this all makes sense. There were giant oviraptorosaur species that could have laid these four to five kilogram eggs,” she says.

Zelenitsky and her colleagues think that Baby Louie probably would have grown as big as Gigantoraptor in adulthood — weighing up to 7100 pounds. But, the scientists don’t think that Baby Louie is the same species as Gigantoraptor. Instead, they’ve identified it as a new one, naming it Beibeilong sinensis.

Both Zelenitsky and Makovicky are happy to finally see Beibeilong sinensis officially join the family of giant oviraptorosaurs. (“I’m just happy it’s finally out there, and we can cite it,” Makovicky says.) Only two other giant oviraptorosaur skeletons have ever been discovered. But the bizarre tubular eggs have been found in Asia and North America — which means that these massive “turkeys on steroids” might have been much more common than paleontologists thought. And there may be more bones still out there.