Ever since Jurassic Park roared into cinemas in 1993, introducing a generation to the awesome of live action dinosaurs and giving us the most famous toilet death in cinema, dino-nerds have been happily picking apart the movie’s scientific accuracy.
Chiming in to the debate with some scientific rigour, the Natural History Museum last week held a special event – Facts, Fiction and Fossils – for a talk with the experts about what the movie got right, what it got wrong, whether what we know has changed in 23 years, and whether it even matters, followed by a screening of the movie. Double nerd whammy.
It was a treat to go to a talk about dinosaurs in the very place established by the guy who dreamt up their name, Richard Owen. And you know you’re getting into something good when your directions to the theatre contain the instruction: “Take the stairs past the stegosaurus.”
Panelists Paul Barrett, a researcher for the museum’s vertebrates and anthropology paleobiology department, and Greger Larson, professor of evolutionary genomics at the University of Oxford, said that while a lot of the science in Jurassic Park is kosher, the book’s author Michael Crichton and director Steven Spielberg did take some creative liberties.
Let’s take a look at those, but first, some context.
In the middle of a polymerase chain reaction
Jurassic Park was published in 1990, in the midst of excitement in the scientific community around polymerase chain reaction (PCR), a new genetic technique that allows researchers to amplify sections of DNA strands.
According to legend, Crichton was inspired by an 1985 article, “Dinosaur Capsule”, where (the now controversial) author Charles Pellegrino predicted that the way things were going with PCR, we’d be able to build our own dinosaurs in 30 years’ time.
*does maths, checks watch, takes a look around, sees no dinosaurs*
Ah well, never mind. It must have seemed feasible at the time – just months before “Dinosaur Capsule” appeared, a team had managed to extract strands of DNA from the fossilised muscle of a quagga, a member of the horse family that went extinct in 1883. By comparing the quagga’s DNA with that of its closest living relative, the mountain zebra, the team could determine that the two had a common ancestor that lived three to four million years ago, which was consistent with the fossil evidence.
Understandably, this got a lot of people VERY excited. What, we can look at extinct creatures’ DNA now? What does this MEAN?
Oh, hi there Reality. Didn’t see you come in. We know now that DNA really doesn’t have much of a shelf life. After a living thing dies, its long DNA strands begin to break down, eventually becoming too small to carry any meaningful information.
A study from 2012 that examined the bones of the extinct moa bird put DNA’s half-life at a pleasingly precise 521 years. The oldest intact genome we’ve unearthed is a mere 700,000 years old – a good 100 times younger than any surviving dino-DNA would be – and it belonged a horse that had been long buried in Canadian permafrost.
Life may find a way, however. Today, as Larson explained, it’s possible to turn certain genes on and off to get the expressions we desire in an organism, so although we can’t (yet) make a complete dinosaur, some researchers are using the technique to give birds dinosaur-like features, so they can study their development.
The Velociraptor/Deinonychus switcheroo
So what you’re picturing as a Velociraptor, the swift, smart predator that has those killer claws on each foot isn’t your real deal Velociraptor (though props to you if you pictured it with feathers. More on that later). No, the Velos in the movie were based on the much larger Deinonychus, which takes its name from the Greek for “terrible claw”. But Crichton thought Velociraptor sounded better.
The Velociraptor weighs about the same as a collie, Barrett noted.
To his credit though, Crichton very faithfully modelled Jurassic Park’s Velociraptors on Deinonychus, even consulting the species’ discoverer, John Ostrom, extensively about how they should behave in the story.
In an interview quoted in Yale News, Ostrom explains: “Crichton, in an apologetic way, explained that in the novel he decided to use the name Velociraptor, that I had said was the closest relative to the animal that I had found… He said, ‘It’s more dramatic.’ And I said I recognise that most people don’t understand Greek.”
The same article continues: “[Ostrom] described Deinonychus as an aggressive and athletic raptor that slashed and disembowelled its prey with those distinctive sickle-claws… Its long and unusually rigid tail provided stability and balance, like a tightrope walker’s pole, during chases and attacks.”
Perhaps the inaccuracy that’s got the most discussion is the dinosaurs’ lack of feathers in the movies. While in 1993, we didn’t have any direct evidence for down-covered dinos (just a hunch), in 1996, scientists in northeast China dug up the first dinosaurs with fossilised feathers. Sinosauropteryx is a close relative of the Compsognathus (the little ones that finished off one of the InGen party in The Lost World), and the branch of the family tree that ultimately gave us birds. They lived about 125 million years ago.
Since 1996, we’ve found about 30 more feathered dinosaurs, mostly in the same area of China. It’s possible that many theropods – a group of dinosaurs that tends to walk on two legs – had feathers, including the Velociraptor. Barrett said that we don’t yet know for sure why dinosaurs sported feathers, but our best guesses are insulation or display.
The studio opted not to integrate this new knowledge into Jurassic Park’s sequels, as it thought the dinosaurs would look scarier without a layer of fluffy but oh-so-stylish plumage.
So… does all this creative licence really matter? Authenticity is overrated, Larson concluded. Ultimately, Jurassic Park is a chase movie that’s served by science, he said. And look – it got a generation wondering about dinosaurs. Some of whom might even be in the lab right now, finding the answers to these paleontological questions. But isn’t pedantry fun sometimes?