More than 20 years earlier, paleontologists discovered 2 partial skeletons of a mystical dinosaur types in New Mexico. This animal, which lived about 92 million years earlier, bore some similarity to huge tyrannosaurs that ruled from about 80 million to 66 million years earlier. One was even discovered with what might have been a partially absorbed lizard skull. However the dino was so small– just about a meter high at the hip– it left researchers to question where it suited.

” There sufficed of a skeleton to be incredibly appealing, however inadequate to nail it down,” states Sterling Nesbitt, a paleontologist at Virginia Tech in Blacksburg who collected among the fossils.

At the time, paleontologists didn’t have lots of other predators in the dinosaur’s size variety to supply a point of contrast, Nesbitt states. Now, residues of tyrannosaurs from Asia and The United States and Canada have actually expanded the Tyrannosaurus rex‘s ancestral tree and enabled scientists to pin the brand-new dinosaur as one of its kin.

Analyses of the freshly recognized dinosaur, called Suskityrannus hazelae, expose that this little tyrannosaur boasted a few of the signature skeletal functions of its megapredator loved ones, scientists report online Might 6 in Nature Ecology and Development This discovery assists light up how small hunters that emerged over 100 million years ago generated such huge, bone-crunching tyrannosaurs like T. rex ( SN: 3/16/19, p. 11).

Like its later, apex-predator cousins, S. hazelae‘s skull was developed for a strong bite, and 3 bones in its feet called metatarsals were pinched together. This bundling of bones is believed to reinforce the ankle, which would have offered dinosaurs like S. hazelae effective hind feet for running and holding down victim, states coauthor Robert Denton, a geologist at the consulting engineering company Terracon in Ashburn, Va.

These functions were most likely essential for the supersize tyrannosaurs, which had such small front limbs that they “ended up being exceptionally depending on their hind feet and their huge tooth-filled jaws to do all business,” Denton states. Finding these attributes in S. hazelae exposes that tyrannosaurs established these functions while still reasonably little.