Speaker 1: Welcome to Brainstuff, a production of iHeartRadio, Hey brain Stuff
Speaker 1: Lauren Vogelbaum here. Many of us first learned about the
Speaker 1: Dilophosaurus through the Jurassic Park franchise. It certainly made them memorable.
Speaker 1: In the novel by Michael Crichton from nineteen ninety these
Speaker 1: dinosaurs spit a sort of gooey poison in the face
Speaker 1: of prey to disable them, and the nineteen ninety three
Speaker 1: film added bright red and yellow roughs or frills that
Speaker 1: pop up from the creature's neck to surround its head.
Speaker 1: The overall effect is scary and beautiful and unfortunately, or
Speaker 1: perhaps fortunately, a completely made up As far as we know.
Speaker 1: Dilophosaurus was, however, one of the few dinosaurs in Jurassic
Speaker 1: Park that lived in the actual Jurassic Period. All of
Speaker 1: the non avian dinosaurs were confined to the geologic era
Speaker 1: called the Mesozoic. Divide the Mesozoic into three periods, the Triassic,
Speaker 1: the Jurassic, and the Cretaceous, based on major changes that
Speaker 1: informed the landscape and climate and life on Earth. The
Speaker 1: Mesozoic era went out with a bang. A mass extinction
Speaker 1: marked the end of the Cretaceous period. Sixty six million
Speaker 1: years ago. Birds were the only dinosaurs that survived the catastrophe.
Speaker 1: Their brethren had a good run, though. The earliest dinosaurs
Speaker 1: evolved around two hundred and forty three to two hundred
Speaker 1: and thirty one million years ago during the Triassic Period,
Speaker 1: a time of great reptilian diversity. The Triassic gave way
Speaker 1: to the Jurassic about one hundred and ninety nine million
Speaker 1: years before the present. Prior to that transition, most carnivorous
Speaker 1: dinosaurs were small bodied. Dilophosaurus was a sign of bigger
Speaker 1: things to come. The beast roamed what was now southwestern
Speaker 1: North America in the early Jurassic period about one hundred
Speaker 1: and eighty three to one hundre undred and ninety three
Speaker 1: million years ago. Dilophosaurus measured over twenty feet long or
Speaker 1: six meters, making it deep biggest known North American land
Speaker 1: animal alive at that time. Compared to many of the
Speaker 1: flesh eating dinosaurs that had existed beforehand, this thing was
Speaker 1: a giant that first Jurassic Park film portrayed Dilophosaurus as
Speaker 1: being smaller small enough to ride shotgun in a jeep.
Speaker 1: As a matter of storytelling practicality, they wanted to distinguish
Speaker 1: it from their larger velociraptors, especially because they were the
Speaker 1: main dino antagonists that poisoned. Spit becomes a flashy, if
Speaker 1: gory plot point in the novel and the film when
Speaker 1: one of the human antagonists meets his just desserts. The
Speaker 1: book explains scientists thought Dilophosaurus's jaw muscles were too weak
Speaker 1: to kill prey and imagined they were primarily scavengers, but
Speaker 1: now we know they are poisonous. There's no evidence to
Speaker 1: suggest that the real Dilophosaurus had a movable neck frill
Speaker 1: or carried poison or venom. Generally speaking, the difference between
Speaker 1: poison and venom is that venom is injected into a
Speaker 1: victim's flesh through a stinger, spines, teeth, or claws, whereas
Speaker 1: poison is applied more indirectly and absorbed through the victim's skin, airways,
Speaker 1: or digestive system. These evolved delivery methods have to do
Speaker 1: with the chemical composition of an animal's toxins. Poisons are
Speaker 1: made up of tiny molecules that can see right past
Speaker 1: the tight barrier of the skin into the victim's body.
Speaker 1: Venoms are made of larger molecules. That are too big
Speaker 1: to do that, so they have to be introduced via
Speaker 1: a wound. All of this would give you the idea
Speaker 1: that a fictional Dilophosaurus spitting would be poisonous, except that
Speaker 1: it mimics the real life modern spitting cobras, which are
Speaker 1: venomous snakes that have adapted the ability to spit their
Speaker 1: venom into a victim's face, where the mucous membranes of
Speaker 1: the eyes, nose, and mouth allow the venom to penetrate
Speaker 1: into the body. All of that being said, a toxin
Speaker 1: spitting Dilophosaurus is fictional, so the technicality of venomous versus
Speaker 1: poisonous doesn't really matter. However, just because this adaptation is fictional,
Speaker 1: it doesn't mean that Michael Crichton pulled the scavenger hypothesis
Speaker 1: out of thin air. The paleontologist who named Dilophosaurus in
Speaker 1: nineteen seventy won, Samuel P. Wells, thought the creature might
Speaker 1: have been mostly a carrion eater. Below the dinosaur's nasal openings,
Speaker 1: there's a distinctive notch on either side of its upper jaw.
Speaker 1: These notches lay at the meeting point of the toothy
Speaker 1: upper and lower jaws, and Wells thought the notches implied
Speaker 1: that these bones were only weakly connected, and therefore the
Speaker 1: Dilophosaurus didn't have a very strong bite. By the time
Speaker 1: Crichton's book came out, there had been a lot a
Speaker 1: lot of debate about this dinosaur's eating habits. The carrion
Speaker 1: concept was one hypothesis. Another imagined Dilophosaurus as a fishing
Speaker 1: specialist that used its long teeth and jaws to snatch
Speaker 1: up wriggling fish. But since then, new research has cast
Speaker 1: the animal in a different light. In twenty twenty, the
Speaker 1: Journal of Paleontology published a study that reevaluated five specimens
Speaker 1: of Dilophosaurus. The authors found that the connection between the
Speaker 1: upper and lower jaws was stronger than Welles had supposed,
Speaker 1: with scaffold like attachment points for stronger muscles on the
Speaker 1: lower jawbones. This suggests that Dilophosaurus actually had powerful jaws
Speaker 1: at its disposal, and bite marks found on a large
Speaker 1: contemporary herbivore seemed to match Dilophosaurus. The researchers also called
Speaker 1: more attention to the dinosaur's trademark feature, its flashy headcrests,
Speaker 1: less flashy than a pop up neck work, but the
Speaker 1: name Dilophosaurus means two crested lizard. The creature had a
Speaker 1: pair of bony ornaments running up along its skull like
Speaker 1: a double mohawk. It's unclear what the top of each
Speaker 1: crest looked like. Scientists don't have any complete specimens to
Speaker 1: go on, but the researchers wrote that the crests were
Speaker 1: quote almost certainly covered in keratin or carotenized skin, Keratin
Speaker 1: being the fibrous protein that makes so many animal body
Speaker 1: structures so tough, like hair, hoofs, horns, fingernails, claws, beaks,
Speaker 1: and feathers. Some modern birds, like the dangerous casswary, have
Speaker 1: bony headcrests sheathed in a layer of keratin based material.
Speaker 1: These coverings can make the crest as a whole significantly
Speaker 1: taller than the underlying bone. So who knows. Dilophosaurus could
Speaker 1: have looked even more flamboyant than its naked skeleton might suggest.
Speaker 1: But if if you're wondering what the animal's twin crests
Speaker 1: were for, join the club. Attracting mates is one popular explanation,
Speaker 1: though it's also possible the crests helped regulate body Temperaturesaurus
Speaker 1: knowledge comes from discoveries made on Navajo Nation land. In
Speaker 1: nineteen forty, a Navajo man by the name of Jesse
Speaker 1: Williams became the first person in recorded history to lay
Speaker 1: eyes on a Dilophosaurus skeleton. Two years later, a group
Speaker 1: of visiting scientists contacted Williams. He took them to a
Speaker 1: Jurassic graveyard where three Dilophosaurus lay exposed. Wells, who would
Speaker 1: name the animal and inspire criton's spitters, was one of
Speaker 1: those scientists. Today, multiple specimens of this dinosaur, which legally
Speaker 1: belonged to the Navajo Nation, are held in trust at
Speaker 1: the University of California Museum of Paleontology. But you can
Speaker 1: see the footprints of large predatory dinosaurs at early Jurassic
Speaker 1: dig sites all over the world, but from the Rocky
Speaker 1: Mountains to New England to eastern Europe. Some may have
Speaker 1: been left behind by Dilophosaurus. Connecticut chose this dinosaur as
Speaker 1: its official state dinosaur in twenty seventeen after trackways made
Speaker 1: by an unidentified meat eating dinosaur from the early Jurassic
Speaker 1: were found there. It's certainly possible that Dilophosaurus or a
Speaker 1: close relative was the predator in question. Samuel P. Wells
Speaker 1: had a long and fruitful career before his death in
Speaker 1: nineteen ninety seven. After Jurassic Park hit theaters in ninety three,
Speaker 1: he didn't shy away from pointing out the Dilophosaurus related embellishments.
Speaker 1: Even so, Wells went on the record as saying I
Speaker 1: enjoyed the movie thoroughly and was very happy to find
Speaker 1: Dilophosaurus an internationally known actor. Today's episode is based on
Speaker 1: the article the real Dilophosaurus makes the Jurassic Park for
Speaker 1: and look tame on HowStuffWorks dot Com, written by Mark Mancini.
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