2014/03/12 by Anthony R. Fiorillo, Ronald S. Tykoski · 1 citation
Earth and Planetary Sciences · #Paleontology and Evolutionary Biology #Evolution and Paleontology Studies #Paleontology and Stratigraphy of Fossils #Cretaceous #Paleontology #Taxon #Ecology #Arctic #Clade #Biology #Geography #Phylogenetic tree
paper · pdf · doi:10.1371/journal.pone.0091287
openalex publication_date 2014/03/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Tyrannosaurid theropods were dominant terrestrial predators in Asia and western North America during the last of the Cretaceous. The known diversity of the group has dramatically increased in recent years with new finds, but overall understanding of tyrannosaurid ecology and evolution is based almost entirely on fossils from latitudes at or below southern Canada and central Asia. Remains of a new, relatively small tyrannosaurine were recovered from the earliest Late Maastrichtian (70-69Ma) of the Prince Creek Formation on Alaska's North Slope. Cladistic analyses show the material represents a new tyrannosaurine species closely related to the highly derived Tarbosaurus+Tyrannosaurus clade. The new taxon inhabited a seasonally extreme high-latitude continental environment on the northernmost edge of Cretaceous North America. The discovery of the new form provides new insights into tyrannosaurid adaptability, and evolution in an ancient greenhouse Arctic.