A dedicated team of paleontologists from the University of Washington and the Burke Museum of Natural History and Culture has successfully unearthed four dinosaur fossils in northeastern Montana during the summer expedition.

The fossils, including the hip bones of an ostrich-sized theropod, duck-billed dinosaur hips and legs, a potential ostrich-mimic Anzu or a new species, and a Triceratops specimen, provide valuable insights into the Cretaceous ecosystems.

These significant finds were made in the һeɩɩ Creek Formation, a geological deposit dating back 66 to 68 million years ago.

Unlike traditional digs that focus on individual fossils, the ongoing һeɩɩ Creek Project aims to systematically sample all plant and animal life from the rock formation, shedding light on the transitional period before, during, and after the K-Pg mass extinction event.

The four dinosaurs, discovered in close proximity on Bureau of Land Management land leased to a rancher, include the ilium of a theropod, duck-billed dinosaur hips and legs, a pelvis, toe claw, and limbs from another theropod, possibly a rare ostrich-mimic Anzu, and a Triceratops specimen. The fossils will be meticulously prepared at the Burke Museum’s fossil preparation laboratory.

Gregory Wilson Mantilla, a UW professor and curator of vertebrate paleontology, highlighted the significance of these discoveries in understanding the dynamics of the last dinosaur-dominated ecosystems and the emergence of the first mammal-dominated ecosystems.

The ongoing project contributes to unraveling the complexities of biodiversity, ecosystem assembly, and the fragility of ancient ecosystems.

While three of the dinosaurs will undergo preparation this fall and winter, the Triceratops specimen, named “Flyby Trike” after the rancher who identified it, will remain on-site for further excavation in the summer of 2022.

The Flyby Trike’s fossils include its frill, horn bones, rib bones, lower jaw, teeth, and the distinctive occipital condyle bone, providing a glimpse into the late stages of Triceratops life before the mass extinction.

The fossils offer unique insights into the pre-extinction environment, with clues suggesting the Flyby Trike likely died on a flood plain and experienced post-mortem disturbance, possibly by a scavenger like a T. rex.

The discovery of amber and seed pods alongside the Triceratops enables paleobotanists to reconstruct the plant life of the һeɩɩ Creek ecosystem.

Visitors to the Burke Museum can witness the preparation process of the first dinosaur, the theropod hips, in the paleontology preparation laboratory.

The fossils, held in trust for the public, will become valuable additions to the Burke Museum’s collections, further enriching our understanding of Earth’s ancient inhabitants and ecosystems.