A skeleton that looks like a small Tyrannosaurus rex is now standing in a Manhattan lobby, waiting for bidders. It was unearthed in 2019 by a Montana rancher, and scientists have since confirmed it belongs to a different predator altogether, the Nanotyrannus.
That confirmation ended a debate that had lasted for decades, and it has turned an unusual find into a headline lot. Its sale touches on a wider question, who should be able to dig up dinosaurs? Learn how it was found, how it differs from its famous cousin, and why scientists disagree about selling it.
The skeleton is nicknamed Jodi after Jodi Pierson, the rancher who found it on her land. Its discovery and excavation were the focus of the Discovery Channel documentary series "Dino Hunters" in 2020. The location is notable; the fossil lay some 8 miles (13 kilometres) from the site where the so-called Dueling Dinosaurs fossil was unearthed in 2006. That earlier find depicts a Nanotyrannus and a Triceratops together, which means one small stretch of Montana has produced two of the very few known skeletons of this predator.
The argument dates back to 1942, when what is now considered the first Nanotyrannus head, known as the Cleveland Skull, was discovered. It is housed at the Cleveland Museum of Natural History. For decades, researchers wondered whether such fossils belonged to young Tyrannosaurus rex. In October 2025, new research concluded otherwise. Scientists examining growth rings inside preserved bones found fully formed adults, not juveniles, which established Nanotyrannus as a distinct genus.
Cassandra Hatton, head of science and natural history at Sotheby's, told The Associated Press that, until the genus was proved, Tyrannosaurus rex was assumed to be the only apex predator of the Cretaceous period, some 67 million years ago. "We now know that they coexisted," she said, each occupying its own niche in the ecosystem.
More than 150 key differences separate the two animals, and size is the most obvious. An adult Nanotyrannus reached about 18 feet (5.5 metres), roughly half the length of an adult Tyrannosaurus rex. Its forelimbs were longer than the famously stubby arms of its larger cousin, and its hand claws were bigger.
The teeth also differed, Nanotyrannus had more of them, slender and almost bladelike, whereas those of Tyrannosaurus rex were thick and almost banana-shaped. Hatton likened the pair to a lion and a cheetah, telling the agency that the slender teeth slashed meat from faster prey, while the big, lumbering Tyrannosaurus rex went after slower animals and ate them whole. It is even possible, she said, that Tyrannosaurus rex ate Nanotyrannus.
Jodi was unveiled on Tuesday 13 October in the lobby of Sotheby's headquarters in Manhattan, ahead of an auction on 27 October with an estimate of $6 million to $9 million. The mounted skeleton stands 6.5 feet (2 metres) tall and stretches nearly 20 feet (6 metres) long.
Hatton said it is almost 70 per cent complete, with a virtually complete skull and a jaw holding roughly 50 teeth. Sotheby's bills it as the "finest and most complete" Nanotyrannus skeleton currently available, a phrase that carries weight because only three skeletons are known.
The Dueling Dinosaurs specimen, nicknamed Bloody Mary, is considered nearly 100 per cent complete but sits in the North Carolina Museum of Natural Sciences and is not for sale. The third is at the Burpee Museum of Natural History in Rockford, Illinois. The auction follows Sotheby's record $50.1 million sale of a Tyrannosaurus rex fossil this summer.
The Society of Vertebrate Palaeontology, an advocacy group of scientists, scholars and students, wants significant fossils like Jodi displayed in museums and other research institutions rather than sold privately. Hatton counters that the world might never have learned of Nanotyrannus without professional dinosaur hunters.
"We absolutely need private diggers who invest their own money," she told the agency, pointing out that there are not enough universities and museums running field programmes. Stuart Sumida, the society's president and a biology professor at California State University San Bernardino, rejected that argument as a "blatant lie".
He told The Associated Press that no peer-reviewed study can be published on specimens that are not held in the public trust, once such a fossil is in private hands, he said, it can never be studied, and generations will never see it again.
