The dinosaurs that resembled birds are believed to have roamed the Northern Hemisphere million years ago.
Researchers have recently been able to identify large-bodied specimens of the ornithomimosaur, which may have been the world's fastest dinosaur at the time. According to a report from Newsweek, by examining fossilised bones from the Eutaw Formation of Mississippi, researchers have bridged a huge gap in North America's fossil record.
The dinosaurs that resembled birds are believed to have roamed the Northern Hemisphere between 145 million and 66 million years ago, the outlet further said.
"An ornithomimosaur refers to a particular group of bipedal dinosaurs, most of which are generally ostrich-like in appearance," Tom Cullen, one of the study's authors, told Newsweek.
"They generally have large eyes, long arms with relatively large clawed hands, long legs, a long tail, and either have small or no teeth...the teeth are absent in later ornithomimosaurs with them having a keratinous beak to assist in processing food," he added.
According to Phys.org, research by Chinzorig Tsogtbaatar of the North Carolina Museum of Natural Sciences and colleagues, published on October 19, 2022, in the open-access journal PLOS ONE, claims that ornithomimosaurs, which resembled ostriches, rose to huge sizes in ancient eastern North America.
The so-called "bird-mimic" dinosaurs, ornithomimosaurs, had short arms, powerful legs, and an ostrich-like appearance. They had tiny skulls. The newly discovered remains, which date back to around 85 million years ago and include foot bones, provide a unique perspective into the development of North American dinosaurs at a period that is little understood.
According to Chase Brownstein, a research associate at the Stamford Museum and Nature Center who wasn't involved in the research, the earliest ornithomimosaur species were all small-bodied and weighed around 26 pounds. Larger species started to develop over time.
"The smallest species, such as the 125-million-year-old Chinese species Hexing qingyi, were barely over a meter long, whereas the biggest one, the 72 million-year-old Deinocheirus mirificus from Mongolia, was a massive, hump-backed, giant-armed animal over 33 feet long," Mr Brownstein told Newsweek.