Apex (dinosaur)

"Apex" is a fossilized Stegosaurus specimen discovered in Colorado's Morrison Formation in 2022. Dated to the Late Jurassic epoch, it is the largest known Stegosaurus fossil, preserving skin impressions and throat ossicles alongside a mostly complete skeleton. On 17 July 2024, the specimen was sold at Sotheby's for $44.6 million to hedge fund billionaire Kenneth C. Griffin, making it the most valuable fossil ever sold at auction. The sale sparked debate among paleontologists regarding the purchase by private individuals of specimens with high scientific value.

Apex is the largest and most complete known Stegosaurus skeleton, with 254 bones preserved out of approximately 319. It measures 3.4 metres (11 ft) in height and 8.2 metres (27 ft) in length.^[1] The specimen is 150 million years old, dating to the Late Jurassic epoch.^[2] The exact species it belongs to is not known.^[3]

It has been compared to the Stegosaurus stenops specimen Sophie, which is currently the most complete Stegosaurus skeleton on public display,^[4][5][6] although Apex has been described as being 30% larger.^[7] The proportions of the specimen have been described as unusual, having comparatively long legs and square-bottom plates.^[8]

Alongside the skeleton, three ossicles from the stegosaur's throat armor were preserved.^[9] Skin impressions from the neck have also been preserved, although the lack of impressions from the lower body means that its sex could not be deduced.^[10] The specimen was found in a death pose, with its tail curled under its body.^[11]

The animal to which it belonged was a large, robust adult, with signs of rheumatoid arthritis such as the fusion of the sacral bones indicating an advanced age.^[1][11] No traces of injuries caused by combat or predation,^[3] or of post-mortem scavenging, are present on the fossil.^[1] According to Sotheby's head of science and popular culture Cassandra Hatton, the specimen likely died of old age.^[11] Bubbles have been found in bones in the pelvic area, understood to have been caused by mating-related infections.^[10]

Apex was discovered in May 2022 by commercial paleontologist Jason Cooper, on privately owned land in Moffat County near the town of Dinosaur, Colorado. The fossil was found encased in hard sandstone. No other fossils were found nearby, although the area is part of the larger Morrison Formation.^[1][4] Excavation of the specimen lasted until October 2023.^[12]

The New York broker Sotheby's, which would later put the fossil to auction, claimed to have worked alongside Jason Cooper since the discovery in order to bring the fossil to the market, documenting the process along the way.^[12][13] According to Sotheby's, the name "Apex" was given to highlight the importance of the specimen within Stegosaurus,^[5] owing to its high degree of preservation.^[6]

Apex was put to auction at Sotheby's in New York on 17 July 2024, with a pre-sale estimate of between $4 million and $6 million.^[14] Seven bidders took part in the auction, which began at $3 million.^[15] After 15 minutes, the specimen was sold to an anonymous buyer for $44.6 million, or 11 times its lower pre-sale estimate. It was stated by Sotheby's to be the most valuable fossil ever sold at auction, as well as the first Stegosaurus to be put to auction.^[2][12]

At the time of the auction, the fossil was mounted on a custom steel armature, in an attack pose.^[13] The missing bones were replaced by sculpted and 3D-printed replicas,^[15] including mirrored versions of existing material.^[8]

On 18 July, the buyer was revealed to be billionaire Kenneth C. Griffin, founder and CEO of the hedge fund Citadel LLC. Griffin intends to put the specimen on loan to an American institution, claiming after the auction that "Apex was born in America and is going to stay in America!"^[16]

The announcement of Apex's auctioning to private bidders gave rise to concern from paleontologists, with Society of Vertebrate Paleontology vice president Stuart Sumida criticizing the trend of major specimens being purchased by private individuals rather than research institutions.^[8] In May 2024, Steve Brusatte commented that Stegosaurus fossils were comparatively rarer than other dinosaur genera such as Triceratops or Tyrannosaurus. Brusatte argued that the skeleton should be displayed in a museum, making it accessible for both scientific and educational purposes, rather than be kept in a private collection, expressing his hopes that the buyer would donate the specimen to a museum for public display.^[17] Both Brusatte and University of Adelaide professor Diego C. García-Bellido stated that scientific institutions were unable to keep up with private buyers at auctions. The pre-sale estimate of $6 million was described as being already out of range for most museums by García-Bellido, who also added that many of them might not have the necessary infrastructure to display the skeleton.^[3][7] The given price range has been described by paleontologist Cary Woodruff as arbitrary given the scientific value of the specimen.^[18]

The display was also criticized, with Sumida commenting that the reconstruction and mounting required artistic choices, which would lessen the scientific and educational value of the specimen.^[8] In a Chicago Tribune opinion, paleontologist Nathan D. Smith suggested that the skeleton be displayed as a centerpiece in the context of the Morrison Formation rather than as a standalone specimen, comparing it to the exhibit of the Tyrannosaurus specimen Sue at the Field Museum.^[19]

As Apex was described as an "unspecified" species of Stegosaurus by Sotheby's, García-Bellido suggested that its identity was either kept secret by the auction house or that the specimen had not yet been well-studied by researchers.^[3]

Both discoverer Jason Cooper and Sotheby's science department head Cassandra Hatton stated that they hoped for the specimen to be acquired by a scientific institution. In May 2024, Cooper stated that the future owner would be able to collect contextual information on the discovery site.^[8] Hatton stated that, despite widespread concerns, she had not seen fossils be lost to private collections, with buyers usually donating them to museums instead.^[18]

• Stan (dinosaur), previously the most expensive fossil to be sold

• Sotheby's auction page