‘Virtually complete’ Stegosaurus fossil goes on sale - but not everyone is happy

A Stegosaurus skeleton described as the “most complete and best preserved” of its kind ever discovered is expected to fetch up to $6 million at auction this summer – but not everyone is happy about it .

The “exceptional” and “virtually complete” dinosaur fossil, which is 11 feet tall and 20 feet long, will be sold as part of Sotheby’s annual Geek Week.

Paleontologists have questioned the sale of such specimens to private bidders, arguing that these finds should be preserved in museums or other public spaces.

Nevertheless, that will not stop the auction of the 150-million-year-old fossil from going ahead in New York on July 17.

Apex, as it has been nicknamed, is the “finest Stegosaurus specimen to come to market,” Sotheby’s said in a press release Wednesday. It is expected to fetch between $4 million and $6 million, making it one of the most valuable dinosaur fossils ever offered up for sale, the auction house added.

Characterized by its distinctive shape, the Stegosaurus was a herbivorous dinosaur with a tiny head and bony plates marching down its back, ending in a spiked tail.

A commercial paleontologist named Jason Cooper unearthed Apex on his private land in Colorado, and Sotheby’s said it was involved in the process from the outset.

The auction house collaborated closely with Cooper to “document the entire process, from discovery and excavation to restoration, preparation, and mounting, ensuring that the documentation and sale of the specimen is handled with the highest standards and transparency.”

This collaboration, it said, “continues Sotheby’s legacy of pioneering Natural History auctions.”

Some, however, see it differently.

Steve Brusatte, a professor of paleontology and evolution at Scotland’s University of Edinburgh, described the specimen as “an important dinosaur fossil,” particularly as there are “far fewer good (Stegosaurus) skeletons than other famous dinosaurs like T. rex and Triceratops.”

This, according to Brusatte, is part of the reason it should not end up in private hands.

“If what the auction house is saying is true, and what I’m seeing in these photos is genuine, then this skeleton really does belong in a museum, where it can be conserved, studied by scientists, and put on display to inspire people from all walks of life,” he said in an email to CNN Thursday.

“It is a great shame when a fossil like this, which could educate and rouse the curiosity of so many people, just disappears into the mansion of an oligarch.”

“Apex” was discovered in the Morrison Formation in Moffat County, Colorado - and very aptly close to the town of Dinosaur – in May 2022. It took more than a year to fully excavate the specimen, which was found to have evidence of arthritis, suggesting it lived to an advanced age, with no signs of combat or predation-related injuries.

The highest bidder will receive a copy of the dinosaur’s scan data, plus a full license to use any 3D data however they choose. This, according to Sotheby’s, “will allow primary information about the dinosaur to remain with the specimen and promote collaboration in future research and education.”

Brusatte argued, however, that research and education would be best served if the fossil was owned by an institution with an expertise in dinosaurs.

“The uber-wealthy will always be able to outbid museums when a dinosaur is sold on the open market, so my hope is that if there is somebody with the means to buy a fossil like this, and this fossil captures their fancy, that they donate it to a museum,” said Brusatte.

“What a legacy that would be — to have your dinosaur on public display, to have your name up in lights as the donor who saved the dinosaur for science, as kids and families stroll by and gawk at this awesome creature from prehistory.”

London’s Natural History Museum is home to “Sophie,” a comparable fossil - though “Apex” is at least 30% bigger, according to Sotheby’s.

Cassandra Hatton, Sotheby’s global head of science and popular culture, described Apex as “simply one of the best fossils of its kind ever unearthed.”

Visitors to Sotheby’s New York galleries will be able to see Apex as part of a free exhibition of some of the items on sale during Geek Week.

Sotheby’s “legacy of pioneering Natural History auctions,” as it refers to it, includes the 2022 sale of an ancient skeleton of a Gorgosaurus, which sold for just over $6 million. It also sold the first standalone T Rex skull with “Maximus” in December 2022.

Stan, the world’s most complete Tyrannosaurus rex skeleton, set a new world record in 2020 when it sold for $31.8 million at Christie’s. At the time of sale, paleontologists feared the fossil was lost to science, but in March the Abu Dhabi Department of Culture and Tourism revealed plans for Stan to be a star attraction at a new museum of natural history, expected to open in 2025 in Abu Dhabi, as CNN previously reported.

Kristen Rogers and Yenny Sanchez contributed to this report.

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