We all know dinosaurs were scary. Tyrannosaurus rex was one of the largest land carnivores of all time, weighing between 11,000 and 15,500 pounds, the equivalent of almost three adult African elephants. Megalodon prowled the seas for nearly 20 million years during the Miocene and Pliocene. While not strictly a dinosaur, the ancient shark was four times longer than the biggest great white. Giganotosaurus was even longer than T-rex, clocking in at 43 feet long, about the size of a city bus.
Now, imagine one of those big bad dinos had venom. That’d be the last thing we need, but it very well could’ve been a reality. In a new episode of Popular Science’s Ask Us Anything podcast, we dig into the fossil record to see just how likely a venomous dinosaur would’ve been.
Ask Us Anything answers your most outlandish, mind-burning questions—from the everyday things you’ve always wondered to the bizarre things you never thought to ask. So, yes, there’s a reason we have baby teeth and no, not everyone has an internal monologue. If you have a question for us, send us a note. Nothing is too silly or simple.
This episode is based on the Popular Science article “Were there any venomous dinosaurs?”
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Full Episode Transcript
Sarah Durn: It’s one of the most memorable scenes in Jurassic Park from 1993. Computer programmer Dennis Nedry—the bad guy—is trying to steal dinosaur embryos. He’s driving out of the park in the pouring rain fast.
Then, he crashes. Mud goes everywhere. His car is very, very stuck.
Desperate to get off the island, he tries to free his car and that’s when he meets Dilophosaurus.
At first, the dino is kind of cute, smallish and chirping, turning its head side to side like a golden retriever. Then, it spreads a terrifying frill around his neck and strikes, spitting deadly venom in Nedry’s face, and with that Newman from Seinfeld becomes Dilophosaurus’s dinner.
The frill on the dino, inspired by Australia’s frilled lizard, is pure Hollywood fantasy. But paleontologists did formally speculate that Dilophosaurus did spit venom, or at least had a toxic bite.
Now, in 2026, we know the species did not in fact spit venom. But what about other species? Were there actually any venomous dinosaurs?
Welcome to Ask Us Anything from the editors of Popular Science, where we answer your questions about our weird world from “Why do parrots talk,” to,” “How does pregnancy change your body forever?” No question is too offbeat or banal. I’m Sarah Durn, an editor at Popular Science.
Annie Colbert: And hello, I’m Annie Colbert, the editor-in-chief at Popular Science.
SD: Here at PopSci, we’re always pondering quirky questions,
AC: And this week we’re wondering were there actually any venomous dinosaurs?
Okay. So Sarah, you just edited a story on this, so please tell us: could any dinosaurs actually spit venom, like our frilly, collared friend from Jurassic Park?
SD: Well, the short answer is no.
AC: Boo!
SD: I know there’s no solid evidence that any dinosaur could spit or inject venom like Jurassic Park’s Dilophosaurus.
AC: So that terrifying frill and venom scene is totally made up?
SD: Pretty much. But here’s the interesting part: Scientists have found some prehistoric non-dinosaur reptiles with venomous fangs that lived around the same time as dinosaurs.
AC: Okay. So dinosaurs themselves probably weren’t venomous. But their neighbors might have been?
SD: Exactly. There’s even a chance some dinosaurs could have been poisonous in a completely different way.
AC: Ooh, intriguing. I feel like there’s a big venom versus poison distinction coming.
SD: You read my mind.
AC: Now before we dig into the fossil record, we wanna know. What questions are circling in your brain hole? If there’s something you’ve always wanted to know, submit your questions by clicking the “Ask Us” link at popsci.com/ask. Again that’s popsci.com/ask, and click the “Ask Us” link.
SD: We can’t wait to hear your questions.
AC: Yes, please give us your questions. We’ll be right back after a quick break with all the prehistoric details. I’m over here doing some Jurassic jazz hands to get pumped up.
SD: Welcome back.
AC: Okay. Before we get back to dinosaurs specifically, I’m gonna take us on a quick detour to talk about venomous animals in the deep past.
Because it turns out venom as an adaptation is really old, like older-than-dinosaurs old.
SD: Oh yeah. It’s super old.
AC: Yeah. So scientists think that the earliest confirmed venomous vertebrate was this small dog sized kinda lizardish creature called Euchambersia. It lived about 250 million years ago, and that’s more than 10 million years before the first dinosaurs ever appeared on earth,
SD: Which is so wild.
AC: Yes. And this thing, it wasn’t a snake or a spider or anything like that. It was actually part of a group of therapsids, which are distant relatives of mammals. So in an evolutionary sense, this venomous creature is kind of related to us.
SD: That’s kind of unsettling.
AC: Right? Like imagine your ancient ancestor had venomous fangs.
SD: I mean, it’s also kind of dope, but also kind of terrifying.
AC: Yeah. Like a cool horror movie, like evolutionary horror. I would watch that.
SD: Yeah.
AC: So scientists figured this out fairly recently using CT scans of fossils. When they looked inside the skull, they found this big hollow area that probably held a venom gland, plus these channels that were leading toward the teeth.
SD: Basically a venom delivery system.
AC: Yes, exactly. The teeth even had these ridges that might’ve helped guide the venom into their prey. So venom was clearly evolving in animals way before dinosaurs were even around. Which brings us back to the big question of the episode: If venom was already a thing, did dinosaurs ever evolve to have it, too?
All right, Sarah, tell us the verdict.
SD: Yeah, so as of now, we really just don’t have enough information to say one way or another.
AC: Mm.
SD: Some paleontologists think there could have been venomous dinos. Others, you know, aren’t so convinced. What we do know is that there were definitely poisonous and venomous reptiles during the time of the dinosaurs.
AC: Uh, gotcha. So Jurassic Park’s large frilled, venom spitting dinosaur is a Hollywood fantasy, but there might have been small kind of non-dino lizards with venom?
SD: Basically, yeah. So Dilophosaurus was a real dinosaur clocking in at 880 pounds, about the weight of a modern day polar bear. So really big. Dilophosaurus actually might have looked more like the film’s Velociraptors.
Despite what Spielberg would have you believe, Velociraptors were actually small feathered dinos. They looked kind of like weird hawks and weighed less than a golden retriever. So not that scary.
AC: Not too scary.
SD: Dilophosaurus, on the other hand, was one of the larger predators of its time, but I will say that awesome frill? That was all made up
AC: Ah bummer.
SD: I know. That said, back when the film came out in 1993, paleontologists actually thought that Dilophosaurus might have been venomous. So Spielberg was basing his portrayal on some real science.
AC: Ooh, really?
SD: Yeah. When Dilophosaurus was first described in the 1980s, scientists noticed what looked like a small depression in the jawbone.
Some theorized that depression might have held a venom gland and that maybe Dilophosaurus used venom because its jaws seemed too fragile to overpower prey.
AC: Gotcha. That makes sense. So the movie wasn’t completely making things up.
SD: Not completely. It took a scientific idea of the time and, you know, just kind of ran with it.
But since then, paleontologists have found much more complete fossils of Dilophosaurus and they’ve learned its jaws were actually a lot stronger than originally thought. And that supposed venom gland? Turns out it was just a misidentified part of the jaw bone.
AC: Ah, the classic fossil plot twist.
SD: Exactly. So today, scientists don’t think Dilophosaurus was venomous, like, at all.
AC: Ugh. Okay, but what about other dinosaurs? Because as we know, there were a lot of dinosaurs,
SD: Tons, tons of dinosaurs. And at one point another potentially venomous dinosaur candidate popped up. In 2009, researchers studied a small feather dinosaur from China called Sinornithosaurus.
AC: That’s an incredible name
SD: One I hope I’m pronouncing correctly. And scientists noticed something interesting: grooves in its teeth that looked a bit like the channel venomous snakes use to deliver toxins. So they proposed that maybe this dinosaur had a venomous bite.
AC: Okay, that must have made some headlines, right?
SD: Absolutely. But later research cast doubt on that theory.
AC: Mm.
SD: Those grooves could have easily had another purpose. And most paleontologists today don’t think the evidence is strong enough to call it venomous.
AC: Ugh. So once again: cool theory, not enough proof.
SD: Unfortunately, yes, and that’s one of the biggest challenges when it comes to venom in the fossil record.
AC: Because venom itself doesn’t fossilize.
SD: Right.
Venom glands are soft tissue, and soft tissue almost never preserves in fossils. So scientists have to look for indirect clues. Things like tubes or grooves in the teeth that might have carried venom.
AC: But even that isn’t foolproof.
SD: Yeah, not at all. Some modern venomous reptiles, like Komodo dragons, don’t even have obvious venom grooves in their teeth, and their venom gland sits under the skin, not inside the bone.
AC: Which means if an extinct animal had a similar setup?
SD: We might never know. The fossil might look totally normal.
AC: That’s so frustrating.
SD: It is, but there are still some fascinating clues. For example, scientists have found a prehistoric reptile called Uatchitodon that lived about 220 million years ago, during the Triassic period, about 30 million years after the first dinosaurs popped up.
Uatchitodon might have looked kind of like a tiger-sized lizard.
AC: Cool.
SD: Yeah. And its teeth have a very clear venom delivery system. Basically a little tube running through the tooth, just like we see in venomous snakes today.
AC: Ooh.
SD: The tricky part though is that we’ve only ever found Uatchitodon‘s teeth.
AC: What?
SD: So scientists aren’t even totally sure where it fits in on the reptile family tree.
AC: Meaning it might not have even been a dinosaur?
SD: Right. But it probably belonged to a group called archosauromorphs, which includes dinosaurs, crocodiles, and pterosaurs. So it was at least closely related to the dinosaurs.
AC: So some venomous reptiles were definitely around when the dinosaurs existed.
SD: Exactly. They just may not have been dinosaurs themselves.
AC: Okay. But earlier you mentioned another twist: the difference between venomous and poisonous.
SD: Right, and people mix these up all the time.
A venomous animal injects toxins usually through a bite or a sting. You know, think snakes or bees.
While a poisonous animal is toxic, when something touches or eats it. Think poison dart frogs or poison ivy.
AC: So venom is like a weapon?
SD: Yeah. And poison is more like a defense system.
AC: Got it.
SD: And here’s where things get interesting. While we don’t have evidence for venomous dinosaurs, there’s a small possibility some dinosaurs could have been poisonous.
AC: Wait, like toxic dinosaurs?
SD: Potentially, because today the only living dinosaur ancestors are birds. And in New Guinea there’s a bird called pitohui that stores toxins in its skin and feathers.
AC: Wait, so now there are poisonous birds, too?
SD: Yeah. And if you handle one, the toxins can actually irritate your skin. And scientists think the birds get those toxins from the insects they eat.
AC: So, theoretically, a dinosaur could have done the same thing?
SD: Theoretically, but there’s a big problem.
AC: Ah.
SD: You can’t detect poison in fossils, because the chemicals and tissues that would carry toxins don’t survive millions of years.
AC: So even if a poisonous dinosaur existed?
SD: We’d probably never know.
AC: Hmm.
That is both fascinating and deeply unsatisfying.
SD: The fossil record in a nutshell.
AC: Exactly. So the final verdict is venomous dinosaurs like Jurassic Park shows us probably not.
SD: Right, but venomous reptiles definitely existed before and alongside dinosaurs. And evolution has invented venom many times in many different animals.
So the idea itself isn’t farfetched, but it just doesn’t seem to have happened in dinosaurs.
AC: Which honestly might be a relief.
SD: Yeah. The last thing the Cretaceous needed was a venom spinning predator.
AC: Yeah. The dinosaurs were already scary enough.
SD: Definitely.
And with that, it’s time for a quick break, but when we come back, I’ll be talking to a real dino pro, Garrett Kruger, one of the hosts of the wildly popular I Know Dino: The Big Dinosaur Podcast.
And we’re back with Garrett Kruger. Garrett is one half of I Know Dino: The Big Dinosaur Podcast that he co-hosts with his wife, Sabrina Ricci. Their podcast has over four million downloads and has featured more than a hundred interviews with dinosaur experts and enthusiasts from all around the world.
Garrett and Sabrina even co-wrote a National Geographic kids book all about dinosaurs.
Garrett, thank you so much for making the time to come on to PopSci’s Ask Us Anything podcast.
Garret Kruger: Thank you for having me.
SD: Of course. So, Garrett, throughout today’s episode, we’ve been digging into the question of whether there were any venomous dinosaurs. Spoiler: Probably not.
But we all know that’s far from the only dinosaur mystery out there. So what dinosaur mysteries keep you up at night?
GK: Well, one of the most enigmatic dinosaurs was probably Spinosaurus because it just has so many mysteries about it, especially with its sail.
SD: Yeah. Can you tell us a little bit about Spinosaurus? What did they look like? And what were these sails?
GK: So we still don’t know a hundred percent what it looked like. We’ve gotten a lot more fossils recently. The first ones were discovered in Egypt, and then we actually lost those during World War II.
SD: Oh no.
GK: But they were rediscovered in Morocco recently.
And then they found the tail, which was another surprising thing, which kind of has a sail of its own.
But in general, it’s just a very long dinosaur. It kind of has a crocodile-like head and it has spines sticking up off of its back vertebrae, which is why it’s called Spinosaurus, and also off of its tail vertebrae we know now.
So it’s a very sail-covered dinosaur too.
SD: Wow. Double sail. I did not know that. So what do paleontologists think these sails were used for?
GK: There are a lot of hypotheses. And scientists, in general, do not agree at all on what these sails were used for. Partly because people don’t know where it lived and where it spent its time.
One hypothesis is that maybe it was showing off for potential mates. That’s probably the most popular opinion at the moment. And yeah, that could also be used in the same way for scaring off rivals, just looking big and impressive kind of like a peacock.
SD: Do you have a favorite theory?
GK: Oh, my favorite is one of the weirdest ones.
Not the most likely I will say, but there are some people that think Spinosaurus sort of waded into water like a stork and then caught fish through the water, and that is a fairly likely idea.
But what is less likely is that maybe it used its sail to sort of shade the water so that it could see through, you know, like getting rid of the sun reflection so it could see through the water a little better.
SD: Yeah.
GK: And then sort of bend around and bite into the shadow of its sail. That was actually peer reviewed published, but it was not widely accepted.
SD: Too bad. I like that theory.
GK: Yeah.
SD: Well, Garrett, thank you so much for making time to chat with us. Where can listeners hear more about what you’re up to.
GK: If you want to hear more about dinosaurs, we have a podcast: I Know Dino.
It comes out every other week or every week for our patrons. And if you just search for dinosaur podcasts or I Know Dino, you will find it.
SD: Great. Well, thank you, Garrett.
AC: That was such a fun interview. I never knew that Spinosaurus had a tail sale.
SD: Me neither.
AC: Right. That’s such a fun thing to say too: tail sale.
All right, cool. That’s it for this episode, but don’t worry, we’ve got more episodes of Ask Us Anything Live in our feed right now. You can follow or subscribe to Ask Us Anything by Popular Science wherever you enjoy your podcasts.
And if you like our show, please leave a rating and review
SD: And let us know if you have a favorite dinosaur? You know, let us know in the comments.
AC: Tell us.
SD: Our theme music is from Kenneth Michael Reagan, and our producer is Alan Haburchak. This week’s episode was based on an article written for Popular Science by Andrew Colletti, and a big thank you again to Garrett Kruger.
AC: Thank you team. Thank you dinosaurs, and thank you everyone for listening.
SD: And one more time, if you want something you’ve always wondered about explained on a future episode, go to popsci.com/ask and click the “Ask Us” link. Until next time, go watch Jurassic Park and keep the questions coming!
AC: That’s a terrible dinosaur. I’m bad at dinosaur sounds.
SD: We’re very little dinosaurs.
The post What ‘Jurassic Park’ got wrong about venomous dinosaurs appeared first on Popular Science.
