One of my favorite movies, which I have seen I don't even know how many times, is Jurassic Park.
I'm honestly not much of a movie-watcher, but the first time I saw this one, it grabbed me from the opening scene and pretty much never let go. Besides the great acting (Jeff Goldblum being top of the list... I've been known to swipe his line, "I hate it when I'm always right") and eye-popping special effects, it also gave us a window into something that has been the subject of speculation for centuries: the behavior of extinct animals.
Some of what Crichton, Spielberg et al. came up with was fanciful and almost certainly wrong; a case in point is the frill-waving, venom-spitting Dilophosaurus that ate the villainous Dennis Nedry. Now, don't get me wrong; it's a great scene, and Nedry deserved everything he got, and more. But we don't know if the crests of the Dilophosaurus were even retractable; this idea came from an only distantly-related reptile species, the Australian frilled lizard. And the idea that it had venomous saliva is a complete fiction, given that spit doesn't fossilize all that well.
Likewise the terrifying pack-hunting and deliberate, highly intelligent distraction behavior ("Clever girl") of the Velociraptors is entertaining fiction, based upon their relatively large cranial capacity, big nasty pointy teeth, and documented accounts of pack hunters like coyotes using a decoy to drive prey toward its waiting pack mates. It's unlikely that Velociraptors (or any other dinosaur) were that smart, and I doubt seriously that any of them could figure out how to unlatch a freezer door.
What's cool, though, is that there are some inferences about dinosaur behavior (and the behavior of other extinct animals) we can make from fossil evidence alone. The iconic scene where Alan Grant and his friends are nearly run over by a stampeding herd of Gallimimus was based upon a set of tracks that may represent exactly what the movie depicts -- a group of small dinosaurs fleeing a larger carnivorous one. (Some paleontologists still dispute this interpretation, however.) But the fact remains that we can use fossils to make some shrewd guesses about behavior.
Take, for example, the tracks found recently of a three-toed theropod dinosaur in the Rioja region of Spain. The species is impossible to tell from the tracks alone, but based upon analysis of the sediment layers, the researchers learned four things:
- The tracks were made on the order of a hundred million years ago, in the early to mid-Cretaceous Period.
- The gait and depth indicates that it was running at about 45 kilometers per hour (right around the top speed Usain Bolt ever achieved).
- Whatever the dinosaur was, it was on the order of two meters tall and between four and five meters from tip to tail.
- Scariest of all, the pattern of tracks showed that as it ran, the animal was accelerating.
So chances are, it was chasing prey. But there was no evidence to determine whether the prey got away or was turned into a Dennis-Nedry-style all-you-can-eat buffet.
A dangerous time, the mid-Cretaceous. While a lot of us dinosaur aficionados would love a chance to go back in time and see what it was like, my guess is that once there, most of us would have a life expectancy of under six hours. So as much as I love Jurassic Park, I'm just fine with not re-creating it.
In any case, it's exciting to know that even though a hundred million years has passed, we can still make some inferences about how these long-extinct animals behaved. Fossils like the theropod tracks in Spain can give us a window into a long-vanished world, and the fascinating, beautiful, and terrifying animals that inhabited it.*****************************************