A Velociraptor confronts a park ranger in Jurassic World. If accurate, the fierce dinosaur would be the size of a dog. (Photo: Universal)

A Velociraptor confronts a park ranger in Jurassic World. If accurate, the fierce dinosaur would be the size of a small dog. (Photo: Universal)

“Jurassic World” is science fiction, with a big emphasis on fiction, and not only because the dinosaurs are cloned. Paleontologists say a number of the lizards are portrayed wrongly to make them fiercer than they were in real life.

The movie, a reboot of the 1993 hit “Jurassic Park,” opens nationwide in theaters this weekend.

It stars Chris Pratt, Bryce Dallas Howard, Vincent D’Onofrio, Ty Simpkins, Nick Robinson, Omar Sy, B. D. Wong and Irrfan Khan.

While the special effects are breath-taking, the film’s realism is tempered somewhat in the eyes of experts because of the way some of the dinosaurs are sensationalized, or worse, created out of whole cloth.

The Indominus Rex, for example, never existed. It was invented solely for the film, according to The New York Times, although most movie goers probably are none the wiser.

Another major inaccuracy involves Velociraptors, which are portrayed as fierce predators. In real life, scientists now know they had feathers; in the movie the appear without them.

They were also about the size of a small dog. In the movie, they are the size of a horse, which obviously makes them much scarier.

In addition to feathers, the dinosaur also had a head like a bird and could not make facial expressions or snarl as they do in the movie, according to Mark Loewen, a University of Utah paleontologist.

Among other minor details, the bird-like dinosaur’s hands are placed wrong, and its tail would have been ridged, not flexible like a cat’s tail, Loewen told The Times.

Like most meat-eating dinosaurs, Velociraptors were more likely scavengers, eating mostly animal carcasses, rather than hunting and killing live prey, according to scientific references.

The size of the Mosasaur was also exaggerated. The sea creature was cloned from blood found in a pre-historic mosquito, but the real one only surfaced for seconds to breathe, making it impossible for a mosquito to land and draw blood, Loewen said.

One of the scariest scenes of the movie shows giant flying Pterosaurs swooping down to snatch children at the theme park.

But it would have been physically impossible for them to do that in real life, not only because their claws were too weak to lift that much weight based on their muscle structure.

Beside the inaccuracies, the movie is mostly true to the look and feel of dinosaurs, broadly speaking, and for Hollywood that’s good enough.

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