Dueling Dinosaurs

The Dueling Dinosaurs or Montana Dueling Dinosaurs is a fossil specimen originating from the Hell Creek Formation of Montana. It consists of the fossilized skeletons of a tyrannosaur (generally considered a juvenile Tyrannosaurus rex) and a Triceratops horridus entangled with one another, and entombed in sandstone. The "dueling" inference comes from the numerous injuries sustained by both dinosaurs, including a tooth from the tyrannosaur embedded within the Triceratops, although it is not known whether they were actually buried fighting one another. Despite the scientific importance of the specimen, it remained obscure for decades due to a lengthy legal dispute over property rights to the specimen, which has since been resolved. The fossil is in the possession of and being studied by the North Carolina Museum of Natural Sciences, where it went on display in 2024.

History
The specimen was originally discovered in 2006 by ranchers Clayton Phipps, Mark Eatman, and Chad O’Connor in Montana. Two different ranching families, the Seversons and the Murrays, owned the land on which the fossils were found.

The Dueling Dinosaurs remained obscure until 2011, when a marketing campaign, including a dedicated website, was launched by the ranchers (with the assistance of commercial paleontologist Pete Larson) to sell them to a prospective buyer. The ranchers unsuccessfully tried to sell the fossil to several museums, including the Smithsonian and the Museum of the Rockies. With no buyers, the fossils were slated to be sold to a private collector instead. In 2013, Larson presented a poster about the tyrannosaur (also referred to as "Bloody Mary", specimen number BHI 6437) at the annual Society of Vertebrate Paleontology meeting, pronouncing it as a potential specimen of the debated tyrannosaur genus "Nanotyrannus". This presentation was met with significant controversy and ethical complaints, due to the opposition surrounding publishing on privately-owned specimens. Shortly afterwards, the specimens went on sale, including auctioning at Bonhams, but no purchase was made.

In 2016, Lindsay Zanno of the North Carolina Museum of Natural Sciences reached out to Phipps, starting negotiations to purchase the fossil, with funds being raised through the private nonprofit Friends of the North Carolina Museum of Natural Sciences. However, legal issues over rightful ownership of the fossils slowed these negotiations; the Seversons had most of the control over mineral rights on Murray land, and whether fossils could be considered minerals (in which case the Seversons would have rights to it) was disputed. Although a previous court had ruled in favor of the Murrays, in November 2018 judges ruled in favor of the Seversons and that fossils could legally be considered minerals in Montana, angering many paleontologists. However, the case was appealed to the Montana Supreme Court in 2020, who ruled that fossils could not be considered minerals, allowing for the Museum of Natural Sciences to acquire the fossils.

The specimens were officially revealed to the public in April 2024, in a ribbon-cutting ceremony led by then-state governor Roy Cooper.

Significance
The specimen is once considered one of the best-preserved and most complete fossils of both species (as well as the most complete Tyrannosaurus specimen ever found at over 98% completeness), and contains skin impressions, and potentially internal organs, stomach contents, and proteins.