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Scientists have unearthed a brand new dinosaur named Janus, the two-faced Roman god of change, for its ability to survive in a chaotic and rapidly evolving phase of North America’s prehistory.
The creature’s most interesting feature, according to researchers, is an unusually powerful jaw, developed to take advantage of the dense new vegetation.
World temperatures were so high in the mid-Cretaceous about 99 million years ago that rainforests rose from the poles of the Earth.
Rising sea levels forced dinosaurs into a heated battle for food and territory. And it was under these conditions that this newly discovered species in North America, Iani Smithybattled it out with feathered tyrannosaurs and early platypuses that came in from Asia.
Scientists have unearthed a brand new dinosaur, Iani Smithynamed after Janus, the two-faced Roman god of change, for his ability to survive in a chaotic phase of North America’s prehistory. Iani battled it out with feathered tyrannosaurs and early platypuses that migrated in from Asia
Paleontologists at North Carolina State University have unearthed the nearly complete skeleton of a young juvenile of Iani Smithy in Utah’s Cedar Mountain Formation, the famous dinosaur graveyard.
The unusually strong jaws of the herbivorous Iani Smithy were packed with giant spatula-shaped, or “spade-like,” teeth, the scientists found, with each tooth sporting up to 12 “secondary ridges.”
Paleontologists believe so Iani desperately needed every extra ridge in its bite to slice through the tough plant material that overpopulates the lush, hypertropical environment of mid-Cretaceous North America.
A rise in atmospheric carbon dioxide during the mid-Cretaceous, as the team notes in their peer-reviewed report on Iani Smithy for the magazine PLoS ONE not only led to warmer climates and rising seas, but also to the flourishing of new forms of plant life.
The researchers say this shifting green choked normal food sources for many other herbivorous dinosaur species, which were less adaptive than the shape-shifting Janus-like Iani.
“We knew something like this lived in this ecosystem because isolated teeth had been collected here and there, but we didn’t expect to come across such a beautiful skeleton,” said the study’s co-author, paleontologist Lindsay Zanno, an associate professor. at North Carolina State University.
“Having an almost complete skull was invaluable in piecing the story together,” said Zanno, who also serves as chief of paleontology at the North Carolina Museum of Natural Sciences.
The jaws of the herbivorous Iani were packed with giant spatula-shaped, or “spade-like,” teeth, the scientists found, with each tooth sporting up to 12 “secondary ridges.” Iani took every ridge to carve through the lush hypertropical foliage of North America during the mid-Cretaceous
Armed with detailed scans of the new dinosaur’s well-preserved skeleton and complex statistical analysis, Zanno’s team came to the surprising conclusion that Iani Smithy shared common features with rhabdodontomorphs – a lineage of dinosaurs rarely if ever seen in North America
Armed with detailed scans of the new species’ well-preserved skeleton and intricate statistical analyses, Zanno and her team came to the surprising conclusion that Iani Smithy shared common features with a lineage of dinosaurs rarely, if ever, seen in North America.
‘We recovered Iani as an early rhabdodontomorph,” said Zanno, “a lineage of ornithopods known almost exclusively from Europe.”
Recently, paleontologists suggested that another North American dinosaur, Tenontosaurus — which was as common as cattle in the early Cretaceous — belongs to this group,’ she added, ‘as do some Australian critters.’
‘If Iani holds up as a rhabdodontomorph,” said Zanno, “it raises a lot of cool questions.”
Zanno and her co-authors speculate that Iani may be the last gasp of its kind on the North American continent before a migration of duck-billed dinosaurs from Asia outnumbered them in the ecosystem.
‘Iani lived during this transition — so this dinosaur really symbolizes a changing planet,” Zanno said in a university press release. “I think we can all agree with that.”