What did dinosaurs sound like?

38m
They probably didn’t roar like lions. Their real voices were likely much, much weirder. We asked scientists to help us recreate these strange, extinct sounds.
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Transcript

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Hello, Meredith.

Hello, Noah.

How's it going?

It's going good.

I'm excited to learn about dinosaurs.

I've been like anticipating this all week.

Yeah, so basically this episode started because

you had a particular question about dinosaurs.

I did.

So basically, I was at the drive-in.

I was seeing the new Jurassic Park movie and all the giant dinosaur roars were coming out of my car speakers.

And I was like, how do they know what dinosaurs sounded like?

We have an idea of what dinosaurs kind of look like from their fossils and from the skeletons or whatever, but how would we know what a dinosaur roar was?

Yeah, so I've been looking into it and dating back to the first Jurassic Park movie, it turns out they really didn't know and they didn't really care that much.

Jurassic Park wasn't really going for, you know, what dinosaurs actually sounded like.

They were going for more of a feeling.

So if you think about, you know, that iconic T-Rex sound, it was this huge roar.

And it was actually made by combining a bunch of different animals.

So, cool.

The basic ones are sort of this low-pitched tiger sound,

combined with some other sounds, and actually, this baby elephant.

And then, other roars through the movies have lions,

some donkey screams.

Classic.

They had some dolphin screeches.

They actually have koala mating calls.

Amazing.

Oh my god.

I feel like I have a new respect for koalas now.

I mean, yeah.

And all of these sounds come together to make that iconic roar.

So most of the animals they used for these sounds were mammals,

which is kind of weird because dinosaurs are reptiles.

Distinctly not mammals.

Yeah, so the sound designer for Jurassic Park actually told this story about the scientist coming up to him and being like, I really don't think the dinosaurs would have sounded like this.

He basically responded, It's a movie.

Well, I'm glad I'm not the only one that has this question.

Yeah, the question is still open, right?

If Jurassic Park was wrong,

what's right?

And that's what I want to tell you about on this week's show.

I want to take on this wild-sounding question of how do you even go about trying to reconstruct an ancient sound?

And especially for our very specific purposes,

what did dinosaurs sound like?

Oh my god, I'm so ready for this journey with you.

Let's go, let's do this.

I'm so proud.

All right.

So before we get to figuring out how people go about reconstructing extinct sounds and what dinosaurs might have sounded like, I just want to set the scene, like how big of a problem this is.

All right.

Not only are dinosaurs gone, but the amount that we know about dinosaurs is just strikingly tiny.

Okay.

We've only found one individual dinosaur for every 10,000 years.

And that's for a hundred million years of when dinosaurs were on the planet.

Yeah.

And because of that, like we're still discovering almost 50 new species of dinosaurs every single year, like today in 2022.

Oh my God.

There's so little we know even about how they look.

Right.

So then when you start thinking about how they sound, it's like even more ephemeral.

It's a significantly harder question to answer.

So in the face of all that, the first basic way to figure out an ancient sound like this is to just look at the actual stuff that made the sounds.

Like essentially looking for a fossilized roar.

How could a roar be fossilized?

So the parts of the body.

that make the roar, like looking for those things, right?

The throat and like

if there's resonance in the hollow bones or something.

All of those words, some combination of all of those words.

So I talked to this paleontologist/slash forensic analyst, Michael Habib, but he told me that finding the equivalent of a fossilized roar is just absurdly difficult.

The primary challenge in reconstructing sound is that most of the sound-producing structures are soft tissues or less resilient hard tissues.

It's muscle and cartilage, and those tend not to fossilize.

Is there like any way that this stuff could get fossilized?

Like, how could you get this information?

There's actually one really interesting example that shows just how lucky you need to be.

Okay.

This isn't dinosaurs, but like 10 years ago, this group of scientists found the fossilized wing of this 165 million-year-old sort of cricket relative.

And wings are the actual things that make the sound for this cricket.

So the scientists were able to just figure out exactly how the wings were shaped, compare them to living crickets, and then just reconstruct what this super ancient cricket sounded like.

I mean, like going back to like the Jurassic Park metaphor, like this, this is the mosquito in the amber, right?

This is almost exactly because this is a cricket.

It's equivalent to finding the vocal cords preserved.

Do you want to hear the sound?

Oh, yeah.

Okay.

So So this is,

I don't want to say for sure, but this might be the oldest sound of a living thing ever reconstructed.

It's so familiar and yet so like different at the same time.

But this is like a cricket sound.

Like it's kind of a far cry from

a dinosaur sound, a far roar from a dinosaur sound.

Yeah.

So is there anything that's like in exoskeleton, but for dinosaurs?

Yeah, yeah.

So this is the sort of the big question, right?

Like if you can reconstruct an ancient cricket sound, can you do the same thing for a dinosaur?

And you sort of can.

Oh, sort of.

Okay.

So one of the most famous examples where we have a pretty good idea of the sound range that was made by a dinosaur is this duck-billed dinosaur called Parasauilophus.

Parasaurolophus.

All right.

Parasaurolophus.

You've actually probably seen it.

What Land Before Time character is it?

It's actually Ducky.

I know Ducky.

We go way back.

Yeah, it's like that dinosaur that has a skull-shaped, like slick back hair or a sort of like ponytail.

The pompadour situation.

And it turns out that that, you know, pompadour is really, really

important for shaping sound.

So that thing on the parasaurolophus head is actually a tube.

That is actually hollow on the inside.

And they connect to the nasal passages and essentially the airway for the animal.

And so when it took deep breaths, it would be forcing air through that set of tubing.

And the idea is that this hollow tube might actually be used to shape the sound that the Parasaurolophus made.

It's like a dinosaur megaphone.

Yeah, or like the cone that a cheerleader shouts into.

Right.

You know, it doesn't give us the actual voice that fed into the cone, but it does give us some interesting clues, like which frequencies resonate best.

So scientists could actually make a sort of educated guess.

It sounds kind of like a foghorn type thing.

Or the vu vuzelas.

Yeah, right.

And then they were like, okay, let's check this a different way.

Would the parasaurolophus have been able to hear this sound?

And it does line up.

The irossicles are the size and shape you would expect to hear that sound range.

It's like its sweet spot.

Also makes sense that they're calling out to their buddies.

Exactly.

So we know which frequencies work best with the tube.

We know which frequencies work best with the ear.

So we can kind of get this sound, even though we don't really know the ultimate sound that was generated into it.

Seems like a good guesstimate though.

It is a really creative guesstimate.

And it was initially done by this guy, David Weisample, who is Michael's PhD supervisor.

And that actually resulted in the staff of the original Jurassic Park film, the 1993 Jurassic Park, calling him for consultation on dinosaur sounds.

Although they didn't like a lot of what he had to say,

they liked some of what he had to say.

They liked the Parasaurolophus thing, and actually, you can hear the Parasaulophus calls in the background of what is probably the most famous scene of that original film, which is where they're in the Jeep and they stand up, and you get the like taking off the sunglasses, amazing look, and you can hear the Parasaurolophus in the background.

Welcome

to Jurassic Park.

You hear those kind of like fog horny things in the background?

Yeah, totally.

You can hear it like echoing off the misty mountainsides.

So to Jurassic Park's credit, they did get the Parasaur Elophus kind of right.

Like we don't know for sure what the voice is that was feeding into that tube, but they did a pretty good job on that one.

Right.

On the other hand, there's another part of that same scene that's really not as good.

So the first big dinosaur you see is a Brachiosaurus, you know, like the big one with the long neck the giraffes of the dinosaur world classic dinosaur right right but they first see this brachiosaurus that's the first big dinosaur they encounter and this is what it sounds like

the brachiosaur itself is trumpeting like an elephant and he had definitely advised them against that

david was like i don't think Brachiosauruses would sound like that.

The big long-necked dinosaurs probably didn't produce much sound.

He said they could probably hiss.

So real brachiosauruses would probably just go shh.

Wait, can you, can you, I missed that.

Could you, could you repeat that?

Yeah, yeah.

So pretend I'm a Brachiosaurus.

It's in my head.

The Noamosaurus.

One more time.

It's just not the sound you'd expect from a dinosaur.

Where would the hiss come from, though?

So this is another sound that you can figure out by looking at actual fossils.

And it all has to do with the neck.

The primary nerves that run the vocal muscles and your larynx and your voice box run down your neck into your trunk and then back up your neck to get to the larynx.

So it's twice the length of your neck.

Okay.

Super long.

And we tend to think of nerves as being instantaneous, but they're not.

It actually takes some time to send a message from the brain.

all the way down the neck and then back up to the vocal cords.

And the thing you're trying to control only works if you can control it quickly.

And if you're a Brachiosaurus with this super long neck, you got a real problem.

Right.

There's no way they could control this elephant kind of voice.

The best they could do was basically just push air out their mouths.

And it's just sort of like, that's this moment of like, okay, we have these pictures of these enormous, majestic, epic dinosaurs.

And it's just hard to imagine them going like,

Definitely not cinematic.

Yeah, not exactly blockbuster style.

And Michael's advisor, David, he knew all this science.

And, you know, he was talking to the Jurassic Park people over the phone.

And this is the part they really didn't like.

He told me the story.

And as soon as he said hiss, there was just dead silence at the end of the phone.

They're like,

really?

Hiss.

They were like, no, that's not how a Brachiosaurus sounds.

You could hear the ancient crickets.

I love imagining him on the phone just like hissing to Jurassic Park executives.

I mean, like, like, okay, so we got the Bronchiosaurus, we got the Pompadour traffic cone situation,

but I just, I need to know what the T-Rex sounded like.

I need that roar, the visceral stuff.

There's got to be something more satisfying than just stomping up and then going,

yeah, I mean, ultimately, even though we have all these fossils, that core voice is sort of a black box.

Yeah.

Jurassic Park's answer to this black box is, let's just get some scary mammal roars.

But there is another way to try and figure out what the actual dinosaur voice sounded like that's not just vibes.

And people are doing this.

Well,

how are they doing that?

I will tell you after the break.

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Okay, Meredith, we're back.

Noah.

Dinosaur sounds.

Dino sounds.

So before the break, you know, we were trying to figure out ancient sounds by looking at fossilized structures.

Yeah.

Concrete things that we can like see and learn from.

So like that parasaurolophus tube, the brachiosaurus neck.

Totally.

But like we said, neither of these tell us about that core voice, the actual thing that made the sound.

But I talked to this guy whose job it is to create sounds from the ancient past.

My name is Johnny Crew, and I'm a sound designer.

Conveniently, Johnny sound designs dinosaurs.

Amazing job.

Incredible job.

What does his business card look like?

His business card is just yippee.

It's brilliant.

I mean, you know, if I was able to go back and tell my six-year-old self what I'd be doing at this point in my life, you know, they'd be amazed, you know.

I mean, who doesn't love dinosaurs?

So Johnny's been working on this Apple TV Plus show, Prehistoric Planet, which has this super scientific approach.

It's kind of the anti-Jurassic park.

The scientific consultant that worked on the show basically came in and he was like, no roaring,

no mammals.

So initially it was a bit like, oh, right, okay.

Because when Johnny made dinosaur sounds for other movies, he used a lot of mammal sounds.

We couldn't rely on any of that stuff.

We had to kind of start again from scratch.

What does that mean?

How do you start from scratch on a dinosaur sound that no one's ever heard?

Basically, you can look at animals that are related to dinosaurs that are alive today and see how they make sounds.

All right.

Who's our dino cousin?

So some cousins that they have, which are especially interesting for sound reasons, are crocodilians.

Crocodilians.

That's sort of a scientific way of talking about crocodiles, alligators, caimans, you know, all of these guys in the same group.

That makes sense.

They seem very dinosaur-y.

Super dinosaur-y.

Here's a crocodile sound.

And you can see the crocodile's got its mouth closed when it's making this sound.

It's making this this sort of rumble.

But if you watch Jurassic Park, you'll see a T-Rex opening its mouth to roar.

And if T-Rexes are more like crocodiles, they probably would have just had more of a closed-mouth rumble.

So it's not just the sound, it's the way it made the sound.

And like the projection.

Right.

And crocodiles like actually shake their body when they do this.

Yeah, there's that thing that alligators do in water, where they kind of

rumble and make the water ripple.

They basically shake the pond.

Oh man, that's terrifying.

Yeah, and then basically just imagine that scaled up to the size of a huge dinosaur.

Even more terrifying.

Johnny told me about this one scene in particular from Prehistoric Planet where he used tons of crocodile sounds.

Crocodilians, yeah, those were the cue.

So this scene is basically showing this big T-Rex kind of guy.

Two-tongues, 12-foot-tall Carnotaurus.

That's David Attenborough, by the way.

Clearing this patch has taken him a long time.

So the Carnotaurus is basically standing in this forest clearing, getting ready to do sort of like a mating call, and you can see his stomach actually going in and out when he rumbles.

Oh, absolutely.

And he's doing this all with his mouth closed, which, from a sound perspective, makes sense to Johnny.

You know, if you're trying to project a sound a long way, your body might need to behave more like a loudspeaker or something, you know.

The vibration comes out through the body rather than just being kind of out through the hole.

His cores are low-pitched and travel much farther through the dense vegetation than higher-pitched ones would do.

We know that bigger things tend to make lower-pitched sounds, so Johnny just kind of pitched the crocodile sounds way down.

I mean, it's the oldest trick, but it's a good one, you know, because it does make things sound bigger.

You know, I mean, if you were to experience that in real life, I don't know,

you wouldn't even really hear it, probably.

You just feel this kind of intense, kind of

low vibration.

And the scientists I talked to said this is exactly right.

When you take a sound like this and scale it up to, you know, enormous dinosaur size, it gets to the point where it's actually infrasound.

So kind of like infrared is too red for us to usually see.

Infrasound is so low it can be hard to hear, which means a lot of a dinosaur call could have been hard for a person to hear.

That's fascinating.

Not only is it like unhearable in the past, but it's unhearable in the frequency.

Yeah, we might not hear it.

Our ear hairs wouldn't vibrate because they're too small.

But bigger parts of our body would vibrate.

Like we'd feel it in our legs or our chest or something.

Oh my God.

Yeah.

So that's crocodiles.

Those are some close relatives, but they're not the closest.

Yeah, aren't dinosaurs related to birds?

Yeah, not just related.

They're actually the direct descendants of dinosaurs.

Birds are dinosaurs.

Yes, 150%.

So I talked to another paleontologist, Julia Clark, and she told me that birds descended from one particular group of dinosaurs called theropods, which include dinosaurs like a T-Rex.

What I show my students, I used to put a roast chicken on the docu viewer in the classroom and you can see the assembly of those structures that are in your roast chicken in the fossil record.

Yeah, I learned how to cook by watching this TV show called Good Eats and like the episode about how to take apart a chicken, take off the breast and the dark mean and whatever, he used a model of a T-Rex to like show all the pieces.

So in my mind, every time I break down a chicken, I'm like, I'm breaking down a tiny dinosaur.

Yeah, and this is something we've known for a while just from looking at the bones.

But then like 30 years ago, scientists made this huge discovery that showed that dinosaurs probably looked like birds on the outside.

On these dinosaurs that we previously related based on their bones to living birds, we find pinnate feathers that are uniquely known in living birds of all the animals out there.

Okay, so like if birds literally are dinosaurs, why bother with the crocodile sounds, right?

Yeah.

You get a lot more information from their direct relative rather than like a distant cousin.

Yeah, it's a great question.

And it's basically because of the specific way that birds make sounds.

Birds have a unique vocal organ.

Birds make their sound using something called a syrinx.

And they're actually the only animals that have these.

You know, when frogs make their noises or I talk to you or bats produce echolocation calls, they're using structures that are located in what we call the larynx.

A larynx is in your throat and the syrinx, the bird vocal organ, that's in the chest.

Right next to the heart.

So I like to say, remember, birds sing from the heart.

But the issue here is that we don't actually know when syrinxes started to appear.

We know that birds have them now, and we know that they're also the the descendants of dinosaurs, but we haven't found an ancient dinosaur that seems to have a syrinx.

So we don't know how far back they go.

So we use some crocodile sounds and then we start thinking about bird sounds, but it's really hard because birds are dinosaurs, but vocally they might be different.

What does that mean?

Like, what do syrinxes sound like?

So Michael, the paleontologist we heard from in the first half of the show, he says that because the syrinx is located deep in the chest, it can make birds super loud for their size.

Think about how loud a little songbird can be outside your window.

The thing weighs like 10 grams, right?

So if the thing weighs 10 tons,

that's a whole nother level.

But his syrinx is also special for a totally different reason.

There are left and right sides to the syrinx.

There's not just one input, there's two inputs.

And the left and right sides of the syrinx do not have to do the same thing at the same time, which means birds, for example, can produce multiple dominant pitches at the same time.

They can basically sing a duet with themselves.

And there are birds that do.

There's some thrushes in particular that their primary songs sound like two birds singing together, but it's actually just one.

They're just using the left and right sides of the syrinx independently.

So this is a wood thrush, and you can hear how it's actually singing two notes at the exact same time.

Wow.

So we don't know how far back the syringxes go in terms of like evolutionary history, but it seems like it could be possible that dinosaurs had them since they're so closely related to birds.

Yeah, it's definitely possible.

So a couple years ago, Julia was looking at a fossil that she'd been working on for a while.

It was sitting on her desk.

It was

from about 67 million years ago in from Antarctica.

It was sort of like like an ancient duck.

Ancient duck.

Ancient duck.

And she CT scanned this fossil and she realized that she could see this faint imprint of a syrinx.

She couldn't see it at first.

It was like really deep in the chest.

Yeah, I couldn't see it on the surface, but we were so lucky because it wasn't crushed at all.

It wasn't broken into pieces.

It was just completely intact.

This is way older than we knew before.

And it takes us back to a time when dinosaurs were still around.

So it raises the possibility that they could have had these.

Now, Julia hasn't found that smoking gun yet, but syrinxes are really hard to find.

Right.

And given that bird sounds are like in the realm of possibility here, I asked Johnny, the sound designer, if he ever used any on Prehistoric Planet.

He told me about this one scene where these two pterosaurs get into this enormous fight because one of them is kind of like invading the other one's nest.

The owner of the nest is back.

Pterosaurs aren't technically dinosaurs, just to be clear, but they're sort of ancient relatives.

I'm going to tell you a secret now.

I've got a very kind of feisty chicken at our house at the back and she's very fierce, you know.

Evil Bluebell is her name and so

sometimes she will just make this squawk and I took the squawk and I slowed it right down.

I mean we're talking sort of eight times.

Suddenly, the richness of that sound and the kind of power behind it and the ferocity was like, oh yeah, that really works.

So that sound that,

that's bluebell?

That's Johnny's pet chicken, bluebell, just slowed and pitched way down.

And Michael, the paleontologist, he says that the bigger dinosaurs get, the weirder their sounds could get.

If dinosaurs had syrines like birds, birds, he says they could have made something like a honk.

It's a honk, but it's like a tuba honk.

So it's like a pulse, a very low sound.

Like just sort of like, bah.

Yeah.

Very different.

Like that, yeah.

Is that him?

That's him.

He's doing his impressions.

I'm just going to play you one more time.

So my attempt at this dinosaur sound was bah.

Not a good attempt.

Here's his attempt.

Oh my god.

Yeah, and because a syrinx could let them make two pitches at the same time, it could get way weirder.

Get to

tubas

and have them play two different notes

as loud as they can.

It's just this kind of war rumble.

And if you think about, you know, other kinds of bird sounds, Michael says there's even a chance dinosaurs could have had a sort of proto-bird song.

It's possible.

It's possible, but it'd be very proto.

So you would expect something a little bit more like the sounds made by somebody like an ostrich or an emu.

Ostriches can make sort of whistles.

And emus can make these kind of weird clicks and clacks.

Oh, interesting.

Google Google Google Google Google Google Google.

Yeah, and listening to that gu-gaga gugga sound, you know, I start thinking of that thrush song from before.

If you pitch that thrush song way down to account for the size of like a huge dinosaur, it starts to sound like that emu.

So here's the thrush.

Here it is pitched and slowed down.

And here's the emu, which could be hinting at a sort of proto-bird song.

Michael says that if it turns out dinosaurs did have syrinxes, they likely would have made some open-mouth sounds.

And if that were true, Jurassic Park might have, you know, a better defense for its open-mouth T-Rex roar.

But all of these possibilities could have been overlapping.

Dinosaurs could have had proto-bird songs, they might have made war rumbles, and they could have done all of that while making closed-mouth crocodile growls.

They might be doing open-mouth sounds with two different tones, and then could also do closed-mouth sounds via rumble, which means that they could rumble.

And while your body's still shaking from the rumble, they could open their mouth and blast you with two non-infrasound, but still very low notes.

While things are still kind of shaking from the rumble, it would be,

it could get real interesting.

I don't know.

To me, it's like more

imaginative, more creative than just the, you know, the big elephant roar.

Okay.

We have all these kind of half-answers.

Some ideas of what dinosaurs could have maybe sounded like based on creatures that we know about now, but it still feels like a bit of a leap.

These kind of feel like pretty speculative.

Yeah, that is a totally valid point because remember, you know, the context of all of this is that we really just don't know that much about dinosaurs in general.

Right.

So sound, you know, is obviously way harder.

But Johnny, the sound designer, he is actually excited about how little we know.

That's the beauty of it, isn't it?

Maybe in 50 years' time they'll be making something different and all the dinosaurs will be talking or something.

I don't know.

Because he'll stumble across that extra special fossil that gives you just that one little extra hint of what it could be or what the missing piece is.

Maybe we'll find that dinosaur syrinx and the next version of Johnny's show, Prehistoric planet could have these war rumble tubahonks yeah i don't know like this is this this wonderful fascinating example of artists and scientists kind of working hand in hand to advance

what we can know about the past you know scientists are are telling us what's possible sign designers are realizing that and they're sort of working hand in hand to help us recreate a lost world in this in this beautiful way well if somebody sees this and it kind of inspires them, you know, that's amazing just to sort of be part of that.

It makes me honestly want to make a dinosaur roar.

Well, I mean, dinosaur roar or

dinosaur tuba honk.

Tuba honk hiss.

I mean, like, let's

put this all together.

Let's build our own dino sound, right?

We got our sound designer, Christian.

Like, let's, let's build this ancient ancient Jurassic world.

What would that sound like?

All right, Christian?

Yeah, let's hear what you got.

So, obviously, I spent most of my time on the T-Rex.

I feel like that's the main attraction.

Okay.

So, I started with a chicken, and I kind of got its bakaw.

I slowed that down and pitched it down because a dinosaur would have lower frequencies.

Wait, that's a chicken?

That's the exact same sound.

Just slowed down a bunch.

On top of that, I added a sandpiper,

pitched it down, stretched it.

Because of the syringx, I layered that twice on top of each other and played them at different frequencies after I slowed it down.

And that sounds like this.

Oh my god, that's a grandifall!

And because of all the talk of tubas and kind of a low note in there, I made sure to add tubas to almost every part of this.

I stretched them out and pitched them down because a tuba is not as big as a T-Rex.

Along with that, there is an ostrich, which I don't think I even touched very much.

And the coup of producer Men Yuen's pigeon, Sunny.

I added alligator just growling.

And for texture, I added an emu throat noise.

There's something about that sound that makes you feel like you're in danger.

And bringing that all together, that sounds like this.

I also wanted to put this T-Rex in a world.

And maybe we can just pretend for a sec that all these dinosaurs lived at exactly the same time.

Okay, yeah.

The wind is rushing through the ancient trees.

There are crickets in the background.

I put a Parasaur Lophus over here.

You can hear a brachiosaurus hissing over there.

A stegosaurus rattling the keratin plates on its back.

There are smaller dinosaurs running around.

Other dinosaurs making tuba sounds.

Clicking, clacking, booming, bellowing.

It's just a really strange, alien and ancient world that even if we're wrong about how it sounded, I'm sure it sounded weirder than anything we could possibly imagine.

This episode was produced by Noam Hasenfeld, who also wrote the music.

It was edited by Catherine Wells and Brian Resnick, with help from Meredith Hodenaut.

We had mixing and sound sound design from Christian Ayala and fact-checking from me, Richard Seema.

The rest of the team includes Bird Pinkerton and Mandy Nguyen who are looking for gossip and for salamanders respectively.

Just one super crucial fact check to note here.

Turns out there's some controversy about what kind of dinosaur Ducky from the Land Before Time actually is.

The official Land Before Time website says she and her family are all Parasaura lofuses,

but some critics and fans aren't so sure.

They think that based on the size of Ducky's wider jawline and her shorter, pointed, and upright pompadora skull cresting, she might have actually been a Saurolophus, not a Parasaurolophus.

Confusingly, other dinosaurs with more proper Parasaurolophus features are depicted alongside members of Ducky's species in the original Land Before Time movie.

Also, despite the similarity in their names, Saurolophuses and Parasaurolophuses are now thought to be only distantly related.

And while we're here, The Land Before Time is not the only popular media we've referenced this episode that has gotten some dinosaurs mixed up.

The Jurassic Park franchise has influentially portrayed Velociraptors as large, scaly predators that hunt in packs.

Scientists now know that Velociraptors actually had feathers and likely hunted solo.

The Velociraptors you see in the movies instead more resemble the Deanonicus.

Michael Creton, who wrote the original best-selling Jurassic Park novel, actually based the descriptions of the story's primary dinosaur antagonists on the Deinonychus and decided to rename them to Velociraptor because he thought that name was more dramatic.

It should be noted that Deinonychus comes from the Greek and means terrible claw, while Velociraptor means swift robber in Latin, so Deinonychus is the objectively cooler name.

I just thought you deserved to know.

If you want to get in touch with an episode idea or any kind of thoughts, you can email us at unexplainable at vox.com.

We read every email.

Unexplainable is part of the Vox Media Podcast Network, and we'll be back in your feed next week.

This month on Explain It To Me, we're talking about all things wellness.

We spend nearly $2 trillion on things that are supposed to make us well: collagen smoothies, and cold plunges, Pilates classes, and fitness trackers.

But what does it actually mean to be well?

Why do we want that so badly?

And is all this money really making us healthier and happier?

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