page_title: Utahraptor
section_title: Paleobiology
hierarchical_section_title: Utahraptor / Paleobiology
caption_attribution_description: English: fossil of Utahraptor
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: Kirkland et al. noted that given the huge size of Utahraptor, it was not fast as Deinonychus or Velociraptor, instead, it would have had a similar speed to the contemporary iguanodonts, and being faster than fellow sauropods. Additionally, the thickness of the tibia indicates that the animal had a significant leg force in order to kill prey.
  It was also suggested that dromaeosaurids such as Velociraptor and Deinonychus, relied on their hand claws to handle prey and retain balance while kicking it, contrary to this, Utahraptor with a much greater weight, may have been able to deliver kicks without the risk of losing balance, freeing the hands and using them to dispatch prey. According to paleontologist Gregory S. Paul, Utahraptor was not particularly fast and would have been an ambush hunter that preyed on large dinosaurs such as the contemporary iguanodonts and therizinosaurs it shared its environment with. Its robust build and large sickle claw indicates it was well suited to hunting such prey. Like other dromaeosaurine dromaeosaurids, it may have also relied heavily on its jaws to dispatch prey—more so than other types of dromaeosaurids, such as velociraptorines. In a 2001 study conducted by Bruce Rothschild and other paleontologists, two foot bones referred to Utahraptor were examined for signs of stress fracture, but none were found.
caption: Cast of the foot bones, Dinosaur Museum Aathal
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