page_title: Utahraptor
section_title: Additional findings
hierarchical_section_title: Utahraptor / Discovery and naming / Additional findings
caption_attribution_description: English: Ungual of Utahraptor, on display at the BYU Museum of Paleontology.
context_page_description: Utahraptor is a genus of large dromaeosaurid dinosaur that lived in North America during the Early Cretaceous period. It was a heavy-built, ground-dwelling, bipedal carnivore. It contains a single species, Utahraptor ostrommaysi, which is the largest-known member of the family Dromaeosauridae.
  In 2018, it was proposed that Utahraptor be the Utah state dinosaur, an act that was approved by the Senate. Initially Utahraptor would have replaced another dinosaur, Allosaurus, as the state's official fossil, but it was decided that Utahraptor would be another symbol of the state.
context_section_description: In 2001, Kirkland et al, pursued a graduate student's discovery of a bone protruding from a 9-ton fossil block of sandstone in eastern Utah. It was determined to contain the bones of at least seven individuals, including an adult measuring about 4.8 m (16 ft), four juveniles and a hatchling about 1 m (3.3 ft) long. Also fossilized with the predators are the remains of at least one possible iguanodont herbivore.
  Kirkland speculated that the Utahraptor pack attempted to scavenge carrion or attack helpless prey mired in quicksand, and were themselves mired in the attempt to attack the herbivore. Similar sites such as the Cleveland-Lloyd Quarry and California's La Brea Tar Pits house such predator traps. Examination of the fossils are ongoing after a decade of excavation, but if Kirkland is correct, it may be one of the best preserved predator traps ever discovered. The fossils may further reveal aspects into the behavior of Utahraptor, such as whether it might have hunted in groups like Deinonychus was believed to have done. However, it was later discovered in 2020 that Deinonychus may not have had complex social behavior seen in pack-hunting animals alive in the modern era, based on differing dietary preferences in adults and juveniles. It is unknown if this lack of complex, cooperative social behavior also extended to Utahraptor. Whether all the Utahraptor individuals were mired simultaneously or were drawn in, one-by-one, is unclear, as work is currently slowed on the specimens. More concrete answers may yet come to light once crowdfunding efforts to employ professional excavator, Utahraptor Project leader Scott Madsen, are completed.
caption: Pedal ungual II of CEU 184v.294 at BYU
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