Cassandra Hatton maintains that Gus’s price is a reflection of how important a specimen is.

“Gus is one of the largest and most complete T. rex ever found; 61% of the bones have been identified; overall, half of the skeleton is found, which is an important scientific find,” he says.

The condition of the bones also provides deep insight into the type of life this creature would have had.

“There’s a huge bite mark on the top of the skull, which could have been suffered during a battle. You’ve got broken bones, some of your ribs, you can see huge lumps where they were broken and healed.”

Cassandra Hatton says she has been contacting museums around the world for months to get them involved in the auction. He wants “something that is scientifically important to be in the public domain.”

But he said the price has to reflect the time, skill, expense and risks of dinosaur recovery. “For many diggers, some of these people live hand to mouth. They are not rich people.

“They have to invest their own money. It’s not the billionaires who dig them up.”

But it’s the billionaires who buy them.

Apex, the Stegosaurus, was auctioned to Kenneth Griffin, founder and CEO of the Citadel hedge fund. Since then, Griffin has loaned Apex to the American Museum of Natural History for four years.

Museums have long relied on wealthy people bequeathing, lending or donating artifacts to build their science and art collections, explains Dr. Smithwick, who professionally recovers and sells fossils.

But unlike works of art, relying on philanthropy from private estates poses a major obstacle when it comes to the study of fossils.

The most respected scientific journals will not accept any study carried out on a specimen from a private collection. It is almost as if it does not exist for the scientific world.

The argument is that scientists need to be able to review the fossil over many years, to agree and disagree, to check their findings as other specimens emerge.

“What happens [if] That person gets bored of them, dies, gets divorced. And there have been many cases where specimens have been in private collections, and there has been a scientific description of them and [that has] disappeared,” says NHM Professor Maidment.

“So it’s not really science anymore.”