Released in 1993 to critical acclaim, Jurassic Park is not without its detractors. Granted, a large part of the issue with the original trilogy now is comparing the dinosaurs of then to the knowledge known today, with recent discoveries and clearer concepts. Critiquing the Steven Spielberg movie for portraying inaccurate dinosaurs cannot be an argument when the portrayal they are compared to comes thirty years after the fact and from Michael Crichton's book.

In reality, Jurassic Park was the most accurate portrayal of dinosaurs at the time. Spielberg had hired several paleontologists for the express purpose of making the dinosaurs as accurate as possible, wanting to bring the public perception up to date with the scientific perception. He succeeded, and Jurassic Park still remains an indelible image in the public perception of dinosaurs, even prompting an entire generation to look to paleontology as a career. However,  that doesn't mean it's without its flaws.

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Grant, Lex and Tim from Jurassic Park

Still, this isn't specifically the movie's fault but rather the fault of its source material -- the book written by Michael Crichton. Despite being written as hard science fiction, some issues slipped by and made it into the book and later the movie. Part of this can be attributed to the book's focus. Unlike the movie, which takes pains to portray the dinosaurs as living animals, the book uses the dinosaurs as monsters to further drive in the message that humanity's hubris in playing God will be its downfall.

That said, some errors in both media come from standing public misconceptions about animal behavior. Doctor Grant's advice to Lex in the movie stems from real advice when faced with a predator: predators chase moving objects because that's what they're hardwired to do. In the Jurassic Park movie, Dr. Grant explains this to Lex in the simplest form possible by saying, "Don't move. It can't see you if you don't move," because circumstances demand it. In the book, the narrative goes on to explain this and bogs it down with the misconception that the T. Rex actually has poor eyesight, which the sequel then tries to erase by claiming the Rex just wasn't hungry at the time -- goat and lawyer are pretty filling, after all.

Other errors are apparent for those familiar with paleontology. The movie's Dilophosaurus is often critiqued for being much too small compared to fossil records, with the most common attempt at explaining this being that perhaps it was a juvenile. Granted, one of the reasons given by the designers was to avoid confusion with the Velociraptors, but the book doesn't describe dilophosaurus as being very big either. It could be that it was affected by the DNA substituted to complete the sequences and bring them back to life. Frogs are much smaller, after all, and there's no guarantee that they weren't affected in ways beyond being able to breed. One of Dr. Wu's arguments in Jurassic World is that the dinosaurs aren't truly accurate for being genetically engineered.

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muldoon about to be eaten by a raptor

But this explanation falls apart with the mislabeled Velociraptor, perhaps the biggest critique leveled at the franchise. Velociraptors were really about the size of a turkey, meaning that the specimens in Jurassic Park would more accurately be described as one of their larger cousins, such as Deinonychus or Utahraptor. This can't be waved off by genetic tampering, as the fossil at the beginning of the movie is described as a Velociraptor. However, it could be the movie trying to maintain consistency with the book, where the mislabeling initially happened, ostensibly due to stylistic choice. At least the movie also offers a nod to Velociraptor's actual size with the kid's comment about the six-foot turkey. Not to mention the discovery of Utahraptor shortly after production began lent some credibility to the design choice.

But perhaps the biggest scientific error -- and one that is rarely mentioned compared to these others -- is the Lysine Contingency. Mentioned in both the book and the movie as a failsafe in case the dinosaurs ever escaped, the Lysine Contingency prevents the dinosaurs from manufacturing the amino acid Lysine; if they aren't fed Lysine, they "slip into a coma and die."  In reality, no animal produces Lysine on its own -- it must be ingested. As Dr. Harding explains in The Lost World: Jurassic Park, herbivores must eat plants that produce Lysine, while the carnivores then eat the herbivores and get the Lysine that way. Again, it is an error that originates from the book rather than the movie.

The good news is these errors don't actually impact one's enjoyment of the movie. Unlike the novel, the Jurassic Park film is a tight movie with a story to tell, characters to love and dinosaurs to be awed at. Sure, they're not feathered but considering that's a recent discovery, it's less of a concern. The dinosaurs are so well-done that even the biggest purist has to marvel at the technical prowess needed to bring them to life.

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