The full fossilized skeleton of a Gorgosaurus dinosaur that roamed 76 million years ago will be auctioned off on July 28, auction house Sotheby's announced Tuesday.

At nearly 10 feet (3 meters) tall and 22 feet (7 meters) long, the well-preserved specimen is a smaller cousin of the Tyrannosaurus rex. It was discovered in the Judith River Formation near Havre, Montana, in 2018. The auction house's presale estimate is that it will sell for US$5 million to $8 million, according to the The Associated Press.

Experts say it's difficult to confirm whether multimillion-dollar auctions of dinosaur skeletons have become more common, but there have been a series of high-profile sales in the past few years.

A Tyrannosaurus rex skeleton named "Stan" sold for a record-breaking US$31.8 million in 2020. Even celebrities like Nicolas Cage and Leonardo DiCaprio have participated in dinosaur fossil auctions.

But to paleontologists, this high-profile auction is part of a worrying trend, in which rare fossils could effectively be lost to science.

Experts in the field say fossils being snapped up by private collectors may prevent them from being viewed by the public and studied by researchers.

"This auction is disgusting," said Thomas Carr, a paleontologist at Carthage College.

Carr added that the fossil is one of only a handful of Gorgosaurus skeletons ever found in the US, as most remains have been discovered in Canada.

"In my career, I have had the privilege of handling and selling many exceptional and unique objects, but few have the capacity to inspire wonder and capture imaginations quite like this unbelievable Gorgosaurus skeleton," Cassandra Hatton, Sotheby's global head of science and popular culture, told the The Associated Press. Sotheby's did not respond to Insider's request for comment.

High-profile auctions, like the upcoming sale of the Gorgosaurus, feed the perception that dinosaur fossils' value is monetary, rather than scientific, Carr added.

"The value of dinosaur fossils is the information that they contain in their bones. Sample size is everything in science, and the auction of one skeleton to a private buyer is equal to the loss of a mountain of data for a scientist," he said.

If a fossil is privately held, paleontologists like Carr fear owners can deny public access to the specimen, or resell it, making it difficult for researchers to conduct long-term analyses, verify previous research, and ask new scientific questions.

Countries like Canada, Mongolia, Brazil, and China have laws in place that protect significant fossils wherever they are found, according to Victoria Arbour, curator of paleontology at the Royal BC Museum in Canada. But in the United States, permits for collecting dinosaur bones are only required if dinosaur bones are found on federal land. It's rare for fossils to be legally auctioned in other countries, Arbour told Insider.

Dinosaur experts say they are concerned that selling fossils to the highest bidder is inflating prices. According to Arbour, most museums work directly with commercial dealers and pay lower prices. Auction prices "are usually far greater than what any museum can really afford," Arbour said, adding, "It does not cost $5 million to collect a Gorgosaurus. It doesn't cost zero dollars, but the profit margins are really high on these auctioned specimens."

Another concern is that pricey fossil auctions may incentivize people to steal bones, rather than leaving them for paleontologists to study.

In May, National Park Service officials said rare reptile track fossils dating back at least 200 million years were stolen from Capitol Reef National Park in Utah, between August 2017 and August 2018. P. David Polly, a paleontologist at Indiana University, pointed to the university's own trove of fossils, used for research. "The more commercial value that's attached to fossils, the more likely somebody will want to break into it and steal something," Polly told Insider.

Not all fossils that are auctioned off become inaccessible after sale. One of the first high-profile fossils sold at auction was a dinosaur named "Sue", the most complete T. rex that had ever been found, which sold to the Field Museum in Chicago for more than $8.3 million in 1997.

If a private individual purchases a fossil, the public and researchers don't have the right to know its whereabouts, according to Arbour. "We don't always know where these fossils wind up, which is how it works," Arbour told Insider.

"It's really unfortunate, because then these really interesting specimens might kind of just disappear from scientific accessibility."

When "Stan" sold to an anonymous buyer in 2020, the dinosaur skeleton vanished from the public eye. It reemerged almost two years later, when National Geographic first reported that it was en route to a future natural history museum in Abu Dhabi. The identity of the anonymous buyer remains unknown, though the fossil's final home in a museum potentially alleviates concerns that it will become inaccessible to scientists.

Though some fossils bought at auction are donated to museums and research institutions, paleontologists like Polly stress that there is no guarantee of that outcome.

"Even the best intentioned collector, once they have died, for example, has very little control over what happens to that fossil afterwards," Polly said, adding, "The long-term availability of it is always questionable when it goes into private hands."

This article was originally published by Business Insider.

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