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Utahraptor (Jura Park)


Utahraptor (Greek for "Utah thief"); pronounced YOU-tah-rap-tore


Plains of North America

Historical Period:

Early Cretaceous (130-120 million years ago)

Size and Weight:

About 23 feet long and 1,000-1,500 pounds



Distinguishing Characteristics:

Large size; huge claws on feet


About Utahraptor:

Probably the biggest raptor that ever lived, Utahraptor measured about 23 feet from head to tail and weighed at least half a ton. This may not seem like much compared to the multi-ton ornithopods and sauropods of the early Cretaceous period, until you realize that another famous raptor, Deinonychus (the stand-in for Velociraptor in Steven Spielberg's Jurassic Park), weighed in at 200 pounds, max. (See 10 Facts About Utahraptor and a gallery of Utahraptor pictures.)

As you might have guessed given its extreme size, Utahraptor had correspondingly huge, single claws on each of its hind feet, each close to one foot in length. These claws were used for slashing and ripping at prey; in fact, Utahraptor may have hunted like a saber-toothed cat, inflicting deep, puncturing gash wounds in sudden ambushes and then withdrawing as its unfortunate prey bled to death. (It's likely that Utahraptor preyed on another famous dinosaur of early Cretaceous North America, Iguanodon; see Utahraptor vs. Iguanodon: Who Wins? for an analysis of how this battle might have turned out.)

Oddly, Utahraptor lived tens of millions of years before its more famous raptor descendants, terrorizing quivering herbivores during the early rather than the late Cretaceous period. It's more often the case that a tiny ancestor will give rise to gigantic descendants, but where raptors are concerned, evolution appears to have worked in reverse! (For the record, Utahraptor seems to have been closely related to the central Asian raptor Achillobator, another sizable feathered theropod that lived about 40 million years later.)


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