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StarTalk Podcast_ Cosmic Queries – Sharks_ with Neil deGrasse Tyson _ Jordan Klepper

Dienstag, 3. November 2026 · 54 min

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Sharks have ruled the oceans for hundreds of millions of years, and their biology is full of wonder. In this soothing video, we gently explore Cosmic Queries on sharks with Neil deGrasse Tyson and Jordan Klepper on the StarTalk Podcast, how they hunt, sense the sea, and survive. Settle in, relax your mind, and drift into restful sleep tonight.

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This is StarTalk Cosmic Queries Edition. I'm your host, Neil deGrasse Tyson, your personal astrophysicist. And today's topic is, you know, we had to get there. We had, you know, everybody's got to do it. Everybody's got to, like, got to do it.

Sharks.

We are sharking. And I've got as my co-host, Jordan Klepper. Jordan!

Neil, excited to be sharking with you.

Okay, love you, man.

Love you, man. We're going to talk about sharks today.

I'm excited.

We're going to talk about sharks, but neither you nor I have any expertise in this at all.

We know nothing about sharks, neither. Between us, we know this girl.

I just know they have teeth. That's all I need to know. They're big and they're hungry.

Spoiler alert, you're ruining this for me, Neil.

So we've got a special guest, Jasmine Graham. Jasmine, welcome to StarTalk.

Hello. Thanks for having me.

Yeah. So I didn't know you could do this. Your degrees are in biology, marine biology, and you specialize in sharks. This is a thing?

It is a thing.

It is a thing. That's a thing. And you've got your project coordinator for Marsilis. What is that? What is that? Mars Silas. I see Mars. But I don't think that's what you got there.

Not that Mars. Not that Mars.

Mars Satellites. That's a whole acronym.

It is an acronym. It has a long name, Marine Science Laboratory Alliance Center of Excellence, which I spent the first week of my job trying to say without stumbling. But we are a program that's geared towards increasing minority participation in marine science.

Okay, cool. And so you're also a co-founder of MISS, M-I-S-S. Yes. Minorities in Shark Science.

Yes.

So that is also a program that's geared towards supporting minority students, specifically women of color in shark science. So it's a little more specific than my Mars by Lace project.

I don't mean to sound, you know, narrow, but that's got to be a hard sell to go up to the hood and say, hey, everybody. Let's go. Let's go find sharks. Right. Is this does that work? Are there is there enough curiosity? Like if I'm growing up in the hood and I'm not thinking about sharks, do you have to overcome that?

So to some extent. So so I think what happens for a lot of people is they bring up this idea of sharks in the ocean at first and then people in their community are like, And they feel self-conscious and they're like, I mean, whenever I told my family, I was going to go study sharks. You're going to get it. Cause they don't even get in the ocean.

They fish, but I mean, they fish to eat. They're not trying to play around with them and figure out what they're doing. So I think the first time that I asked like, what does sharks do? Or sorry, what does fish do when they're now on our plate? People were like, who cares?

Yeah. Yeah, yeah, yeah. If you're going to be tasty, I don't need to know what you do in the ocean. Wow. So very cool. So, so, so Jordan, you collected questions from our fan base.

Got plenty. People are excited to talk about sharks.

You know, and so sharks spilled over out of the other places into StarTalk. We had to go there. All right. So Jordan, give it to me. What do you have?

Let's jump right in with, uh, Bike and Bird Patreon subscriber. He's got a question. How affected, if at all, will sharks be affected by climate change? At what temperatures do the waters have to stay for them to remain comfortable?

Oh, I love that question.

Yeah.

Yeah. So what's going on there, Jasmine?

So that's a really great question and something that a lot of researchers are interested in figuring out. So sharks can't maintain their own body temperature. So unlike us, where we run the same temperature, unless we have a fever, they can't do that. So they are greatly affected by their environments. And so... things like climate change are things that are definitely going to be affecting sharks. We don't know how much. We don't know at what point it becomes something that they can't deal with anymore. As far as what's the ideal temperature, that varies with sharks. So some sharks live at really cold, I mean, for a shark, cold temperatures, and then some are like in the tropics.

So It depends. And there's a specific ideal temperature for every species of shark. So researchers are really focused on the individual species and how they're going to be affected. And then another important thing is their habitat. So there's a lot of sharks, especially the small coastal sharks, that depend on things like mangroves and reefs and seagrass. And so when those go away.

The little sharks, they just bite off a limb or a few fingers.

Right.

The little sharks, the little.

Sharks, the little sharks are just swimming around, living life.

We don't have to have nightmares about the little sharks.

That's what I'm wondering.

I just want to know what we have to worry about.

Yeah. I just want to know when do you need the bigger boat? Right.

So, yeah. Yeah. The most most sharks are going to be like. so small that you're not even like thinking about them. So they're just swimming around. Of course, the really big ones are the ones that get all the attention, the great whites and the tiger sharks. And they are, they are above average size. Most sharks are just like hanging out at like four or five feet long and they're just chilling. Most of the sharks that you're going to encounter, like going to the beach and stuff like that, you probably have a shark within, a hundred yards of you at all times, but it's probably like two feet long.

Now you tell me this, but so do the little sharks just bite off your finger, that's all?

The little sharks just like swim around and usually they get scared really easily. So if you make any sort of movement, they're gonna be like, oh my goodness, that is a big animal. And I don't know what that is, run away.

I mean, I'm even afraid, do they brush against your thigh? That frightens me.

I mean, yes. If you're in their way and they're swimming, yeah, they'll bump into you.

These stories are frightening. They're all frightening.

I guarantee you, Jordan, that shark that touched you is freaking out. Like, oh my God, I touched a thing and I don't know what that is. You're both freaking out. Everybody's freaking out. Just let it happen.

It sounds like high school. You know, we don't know what the boundaries are. Somebody touches somebody else. You're freaking out internally. It's more about what's going on inside than anywhere else.

So Jasmine, let me hypothesize something. I didn't know sharks were very sensitive to their environmental temperature, you know, the water temperature. So if that's the case and you have global warming, the water temperatures rise, they might have to swim to a lower depth where it's cooler than they previously had been. And that would change the food available to them. Is this a possible scenario in a, like the climate changed future for sharks yeah.

That's that's definitely a possible scenario and and you know if your prey moves you gotta move like if you're eating fish and all the fish swim over here and you can't follow them that's a problem that's.

The end of you yeah that's right right darwin fixes that immediately right right very cool all right jordan.

That was actually the uh the That was the first rough draft of the Jaws screenplay. It doesn't end with a gunshot. It ends with the slow building of temperature change and the inability to regulate body temperature. It was about a seven-hour film.

And they had to evolve the shark so that it fed at a different depth, right? It took a while.

It's hard to tell that in any kind of official way. So they're like, you know what? Screw it. Let's have them shoot some kind of canister in his mouth.

Yeah.

I got a question here from another Patreon subscriber, Brian Flowers. My girlfriend Laura would like to know, with so much of the ocean unexplored, can it be said definitively that the Megalodon is extinct when tooth specimens not matching their extinction dates have been found?

Ooh. Tell me about the Megalodon. There's a movie, right?

There is a movie called The Meg, which is an interesting experience. I knew that we were going to be in for a wild ride when the poster came out and the Megalodon had like 13 gill slips. That is like twice as many gill slips as this thing should have. But yeah, so a lot of people ask that question.

I'm sure Jordan thought the same thing when he saw the movie poster.

I was like, you know what? I'm all in, but this doesn't feel at all relatable. through the research said, I'm gone.

The authenticity just went out the door.

Statham is usually so good with authenticity.

Yeah, so yeah, lots of people ask that of like, well, how do you know? Okay, first of all, they were ginormous, like ginormous. And it's not like they were living in the deep ocean. That was not the case. It's not like, oh, they could be down deep in Mariana's trench and we could drill them up accidentally. No, they didn't live that deep.

That's not a thing that was happening. Also, the biggest way that you can tell is by the size of our whales. So- Whales are really big now. Whales didn't always used to be big. They used to be small and fast. And the reason why they were small and fast was to avoid being eaten by the megalodon. So that was their main like defense against getting eaten by a Megalodon was like, all right, this thing is really big.

I just got to be really fast. So they would be really small and really fast. And then Megalodon went extinct and then was the rise of the great white shark. So now we have a shark that's much smaller and much faster. So then the whales strategy kind of changed a little bit. So they actually evolved to be so big that it would be a hassle for the great whites to try and eat them. So if they were all super big and slow during the time of Megalodon, they would have 100% gotten taken out. Like Megalodon would have been like, ah, a sperm whale. This is just a light snack.

Okay. So what you're saying is they weren't bottom dwellers. So you would see them. You would see them. You can't hide a huge animal.

Yeah.

And their prey would... That's interesting because one way to know about whether an animal exists is whether its prey is rampant in an area. And then you say, well, it can't be that many foxes if you see many rabbits, right? This is a fair evolutionary statement to make, I guess.

Yeah.

Or ecological statement to make.

Yeah. Things co-evolve together and, you know, whenever the thing that they're trying to avoid happens, goes extinct, they're like, woohoo, free for all.

We can get as big as we want now. I got to defend the movie one last chance here. So if the megalodon is extinct and gills are not made of fossilizable tissue, how do you know they didn't have 13 slits? So that I- Am I good there, Jordan? Jordan, I think I got her on this.

Neil, I think this is you. You said you came into this saying you didn't know about sharks, but you are making.

Some nice jokes. This is a slap down. Okay, yeah, go on.

So gill arches fossilize. So cartilage doesn't fossilize nearly as well as bone. Um, but you know, cartilage does fossilize and, and we have a lot of scientists, not me, this is not my field of expertise, but a lot of scientists do a lot of work on reconstructing from what little evidence that we do have. Um, so yeah, we don't have a lot of, of evidence of megalodon, but we do have all of their relatives and none of their relatives have 13 gill slips. So It is highly probable that they didn't have 13 gill slits either, even though we don't have, you know, all of the fossils and everything like that. And we're doing a lot of estimating and guesstimating. So can I say 100 percent that they didn't have 13 gill slits? No, I cannot. But

the chances of sharks going from 13 gill slits to five. That would be a lot of changes that we need to.

I got you. Okay, that's fair. Very fairly argued there, I think. It's like.

I don't know, Neil. Neil, push back on that science. If you're trying to base it on, like, my weird uncle, if you're using my weird uncle to date whether or not I'm going to be a 350-pound conservative from Indiana, it's just not going to match.

Well, that's what happens, because, you know, the anthropologists, they find the one skeletal remains... And then everything about the entire species is anchored to that. So if they found your uncle, and that was the representative human of all humans, you know, you're saying we'd have issues.

We would have issues. As long as they don't go looking in suburban Indiana, then he's not going to be the original man.

The fossilized version of the original man. So a variant on this is, do you portray your dragons with four limbs plus two wings? Or that is one, two, three, four appendages plus two wings, or are the front limbs, the wings. Okay. And so, uh, in, in game of Thrones, the dragons, the front, the front limbs were the wings as this true with bats and any other sort of vertebrate that flies. So you can't just throw in another pair of appendages and. in the model that we have here on earth. So is that a fair analogy, Jasmine, do you think?

Yeah, definitely. I mean, you have to use what information you have and yeah, we're drawing dinosaurs and prehistoric creatures and stuff to the best of our abilities. And sure, we get things wrong, but we do have a blueprint. You know, they didn't totally... change shape that quickly. That's not how evolution happens. You don't go like, oh, and then suddenly there was an individual born that had an extra pair of limbs. And then they procreated with another individual that had an extra pair of limbs. And suddenly everyone had an.

Extra pair of limbs.

That's not how that works.

That's very bio 101 right there. Evolution 101. All right, Jordan, what else you got?

I got another Patreon subscriber, Joy Pinero Denise. Considering mammals return to the ocean and dominate it, have sharks reached an intelligence plateau? Would climate change ironically provide an opportunity for sharks to adapt and become more intelligent?

Ooh, I like that. First, Jasmine, set it straight. The mammals in the ocean did not evolve there. Is that correct? I mean, they were mammals on land and returned to the water.

Yes.

That is crazy.

Yeah.

There's a lot of back and forth. So like, so we have life starting in an aquatic setting. Then there was some that went to land and they did all this evolution on land. And then they were like, you know what? Land is like, I'm just going to go back.

Land is overrated.

Like Tulum. You're like, oh, it was cool for a little while, but I'm coming back.

They went back into the ocean, which is weird because the ocean can kill us as humans, right? You don't, this is not a first thought. And so for some species to have that thought, they've got to have some pretty good adaptable elements to them. Yeah.

So you, I mean, you have, especially where you had situations where there were major predators on land and they couldn't go in the water. So why don't you just run into the water and then the predator can't get you. And then, you know, you have some individuals that are born with some special adaptations that help them in the water.

And then they're more successful because they can hang out in the water and avoid the predators. And then that just kind of builds and builds and builds and builds and builds. So you have this, this situation where you're like, there are lots of dangerous things on land that are trying to eat me. Wouldn't it be great if I didn't have to contend with those individuals. And so that's kind of how this directional shift happens. And then you also have things like, you know, big asteroids and stuff, just like decimating the air quality. And if you were in the water, you didn't breathe air. You're like, haha, joke's on you. That's not a problem for me.

That's cold. You're going to carry on like that. That ain't right. Also, it seems to me that a lot of the the aquatic mammals have a very significant fat layer on their bodies. So if you were sort of fatter, plus fat is more buoyant than muscle, so if you were a fatter mammal, you could survive lower temperatures in the water relative to other mammals, and you wouldn't have to come out as soon. So I see how this could lead to this. So yeah, so in the future, if our only salvation is the ocean, the skinny people all die.

What?

Oh, no. Your crazy uncle, Jordan, he knows what's up.

He knows what's up.

I was going to say, as you were saying that, I was like, oh, the larger folks survive longer. He might do okay in Indiana.

We got to take a quick break, but when we come back, more with Jasmine Graham. We're talking about sharks, past, present, and future on StarTalk. We're back. StarTalk. My co-host, Jordan Klepper.

Jordan.

Neil. Neil. Sharks. I'm, you know, we started this and we both agreed that we were walking into this with a certain amount of ignorance. And I'd like to think, uh, I've learned nothing up to this point, but that's, but that's not because the information isn't good. It's just, it's really hard to get through me right now. I'm still thinking about the logistics of the movie, the Meg, but I'm going to get.

Okay. So you just confessed the density of your skull to both of us.

Oh no, I was, I wasn't supposed to tell anybody.

Uh, so Jasmine, you, um, You have a master's degree in biological sciences at Florida State University. Florida, there's a lot of marine science in Florida colleges. Isn't that right?

There is. I mean, we're a peninsula. We got a lot of ocean.

You got a lot of ocean. Plus, you're going to be gone in the global warming. Oh, yeah.

Miami is gone.

Gone, yeah.

Sorry, Miami.

Florida, like the average sea level in Florida is like an inch. Still lucky high tides don't take them out every single time.

Colleges in Florida having to do with climate change and also the way we fund upper education. Not something to invest in.

Not the best combination there. So how long have you been interested in sharks?

Since my freshman year of college.

Okay. So did you watch Shark Week or something on Discover Channel or something?

I did watch Shark Week when I was a kid. And yeah, we watched a lot of Discovery Channel. But I didn't think about sharks, really. Like you study them. That was not a thought that crossed my mind. I actually didn't even know that you could be a marine biologist as a career until I was like a junior in high school. And then I was like, what? You can get paid to do this. and then i went to college and i i met a professor who did shark science and and did the evolution of study the evolution of sharks and he was just super excited about sharks and then i just got excited by osmosis i was like sure i'll just come work on sharks and then the more i got into it the more i was like whoa sharks are really really cool i'm gonna

study sharks.

Forever excellent excellent Because they're so different from other marine species. Just everything I read, they don't have bones, right? They just have cartilage. Is that right?

Just cartilage.

So their teeth are stronger than their scaffolding.

Yeah. Which is important if you're a predator. Like that's important. You got to be flexible and nimble to chase things and you got to have strong teeth to eat them. It's like, it's a perfect design.

Perfect killing machine. All right, Jordan, you got more questions for us.

I do. We've got a question here from Facebook. This is from Kevin Hardy. Why are surfboards and wetsuits painted black to make humans look like seal food to sharks? Why don't we use high contrast zebra prints to break up the silhouette? Ooh.

So, so, so wait, wait, just to understand, if you look up from below the, the, the shadowing of the surfboard, it looks like a seal. I didn't know. I didn't know that. That's what this implies.

Okay.

So Jasmine. Yeah. So what the surfer community, they almost take pride when they show you their shark teeth scars, right. That they survived it. What, what, what's your responsibility to them?

So, yeah. So if they, you know, if a shark is looking up at them and they're on the surfboard, yeah, it does kind of resemble a seal or something that is actually shark food. Um, and, and so, yeah, like with the, with the coloring and the pattern and stuff, that's not going to really make a huge difference because sharks aren't really going to be able to tell that you're zebra print from. Like if they're looking up at you, they're just looking at the outline, at the shadow. So the best thing to do is to try your best not to look like a seal. So like try not to flail around and definitely don't surf in areas where there's high shark activity. So like if there is, you know, some bait balls or something, bait balls are like huge

clouds of fish swimming really fast in one direction, right? They're running away from something. You should probably move. Just be observant.

Take your cues from other species.

And, you know, if you have any sort of dead or decaying animal around, then yeah, don't go. So like there's a movie called The Shallows that came out a while ago where she's like surfing by this big decaying whale thing. And I'm like, first of all, Why? There is a large decaying animal, just like a smorgasbord for sharks.

And you're like, I'm going to go surf right here. And then I'm going to get knocked off my board and I'm going to climb on the dead whale. Why is that a decision that you made? Just stay away from things that sharks eat so you don't get confused with food. Because, you know, usually you have shark bites.

And for the shark, it's like, hmm, I wonder what this is. I wonder if this is edible. Chomp. Ew. Nope. That's not what I thought it was. Swim away. But, like, that little chomp is like, whoop, there goes your leg. So you don't want to even be in a situation where the shark is confused and needs to check you out. Just, like, you know, keep your distance away from things, like, huge bait balls or like where people are fishing or dead decaying animals and just if you if you have a lifeguard or someone tell you like hey there are sharks mating in this area i don't think it's a good idea for you to go surfing don't say like this is america i can do what i want you can but that might not end.

Well this is america i'm So.

As long as Americans are just logical and think through things, we'll be fine. I don't have a lot of faith.

So, Jordan, give me some more. You know what?

We're going to stay on this movie-inspired idea. Somebody really wants to know. Cameron Jefferson from Facebook. If a tornado started over a school of sharks, what would really happen? Bit.

I don't know what you're talking about.

I'm sorry to say.

No, no, wait, Jasmine and I don't know what they're asking about.

Neil, you know Neil. Neil, admit it. You and I have talked offline about Sharknado for hours.

No, we have not.

It's your favorite movie. You have posters up right now. People can see your office. It's nothing but Sharknado posters.

All right, Jasmine, what's up with that?

So as glorious as it would be for an entire school of sharks to be lifted up in a tornado and just like plopped at another location. No, sorry. But it would be so cool.

And like, But Jasmine, you're undermining the main premise of that movie series.

It's still a great movie series because it is utterly ridiculous and super entertaining. And don't let that stop you from enjoying Sharknado. Like, don't let it stop you.

It doesn't claim.

To be accurate. That's not what it's claiming to do. It's claiming to entertain and it succeeds.

I thought it was based on a true story. That's my bad.

Yeah, the great Sharknado of 1917.

So Jordan, I don't know if you guys know, I had a cameo in Sharknado 6.

I didn't know that. You were in Sharknado 6?

Yes, I had a cameo. And I was overlooked by the Academy. I thought, you know, I thought that performance was totally worthy of some kind of award.

Do you remember your line from Sharknado 6?

No.

I played Merlin. And because in Sharknado 6... I bet you didn't know there were five other sharknadoes.

I was going to say, there's multiple surprising pieces of information.

Jasmine, did you know there were six?

I knew there was a lot, but I didn't know the number.

Yeah, yeah. So in this one, the tornado opens a portal through the space-time continuum and goes back to medieval days. And in so doing, shark DNA merges with dragon DNA. So you have shark-dragon-nadoes. And I'm in the medieval times, dark ages really, and I play Merlin, and I do actual science, but people think it's magic.

That's a pretty good call.

That's what I thought. That's what I thought. I could do that. I could do that. And I think I ride one of these shark dragons in the tornado. I was on a green screen, you know, rocking pony, but... Yeah.

But a hard question. How many limbs did this dragon have?

I don't even remember. But Jasmine, I'm very proud of you and delighted to hear that you were entertained by this movie series without being distracted by the little bit of science that got wrong. So Jordan, give me some more.

Let's head to Facebook. We got Manuel Arguello. He asks, what innovation used today can we attribute to research done with sharks? Actually, I like to put, Neil, we've talked in the past about our love of space, our love of NASA, and all of the fun innovations that come from focused on trying to get to places like the moon.

Right, you did a whole special when you visited NASA headquarters.

We did, yes.

Not headquarters, one of the centers, yeah.

Yeah, we talked all about that. Even those who are frustrated about our... our attempts to get back to the moon or to Mars, it's the byproduct of that kind of ingenuity is bad.

Yes. So Jasmine, can you justify what you do?

That's the more direct way of saying it.

Just, I get that all the time. So let me, now I get to dish it out to you. Hi, Jasmine. What good is it for the rest of us?

So there's, there's a lot of materials that come from sharks that people use and things like lotions and medicines and and makeup and stuff like that. There's a compound that's found in their livers, which helps them be buoyant, that people use on a lot of different things. Also a lot.

Of- Wait, wait, I didn't know sharks wore makeup.

They don't, but people do. And yes, for all of you people out there that are right now looking at your lotions and being like, it doesn't say anything about sharks. It usually calls it like squalene or squala something. That is shark liver.

Shark extract.

Whatever you're putting that on your face. Okay. There's also been a lot of engineering feats that have been based off of the hydrodynamics of sharks because they've spent millions of years evolving. They're super speedy. They cut through the water super fast. So a lot of that engineering principles when they're designing underwater vehicles and things like that comes from you looking at the structure that evolution has already provided as the winning structure, which is the sharks.

I thought I remembered, wasn't there some bathing suits in the Olympics that people wore that I, am I remembering this correctly? That was inspired by shark?

Yeah. So they had denticle or things like denticles, which are these modified scales that sharks have. They kind of look more like teeth actually. And here's another phrase that I can drop, Jordan, as someone that's got in shark burn a lot, it really hurts whenever they rub against you. They are sharp. They are sharp little things. And yeah, shark burn is a thing if a shark rubs against you.

Okay, but wait, wait. So, but why would you make a swimsuit out of that that resembles that?

Because it helps them cut through the water really quickly. It cuts down on drag and friction as they're moving.

Through the water. Oh, okay. I get it now. Because you can have things that look like they would interfere, but what they do is they break up turbulence and force much more laminar flow where you can go through. Okay, I'm with you on that. Very interesting. And something else about the teeth. Anything we can learn about the fact that they have multiple teeth, multiple generations of teeth?

Yes, they have rows of teeth. So basically their teeth are just always good to go. So, you know, you chip teeth. I mean, they're eating things that are really tough and they're tearing at stuff and they're like, oh, I chipped a tooth or my tooth fell out, whatever. There's another one back here and it's just like, whoop.

And so they just always have fresh teeth. It's like, Whenever you have knives, your knives get dull and you have to like resharpen them. How cool would it be if like you used your knife and it got dull and you're like, it's fine. I got another knife right here. It's just like super useful.

So it's because sharks are so different from all other aquatic fishes that it gives us these sort of unique, interesting questions and solutions regarding them. Is that a fair characterization?

Yeah.

And I mean, they do lots of really cool things. Like they heal super quickly, which is something that we as humans are like, hey, how do they do that? That might be something that's useful. How are they healing themselves? Maybe we can use that in medicine and things like that. There's a lot of diseases that they don't get that we are interested in researching and trying to figure out what makes them resistant to those types of things. And can we recreate that and use it in human medicine and stuff like that. So there's a lot of things, whenever you have something that has been evolving for so long, it's like, why reinvent the wheel? Nature already figured out what works. Like humans aren't going to do any better.

We should just like borrow what nature already figured out. We could figure out a way to make it useful to humans.

Okay. So what's left unsaid here, Jordan, is to get all of these products and to study the shark in this way, you have to kill the shark.

Sometimes you do, yeah.

Yeah, yeah. It's not like we're studying primate livers and making lotion out of it. There'd be objections to that. So I think since sharks like to eat us, we don't have any problems killing them for whatever purpose that can serve us in return. It's unspoken, but that's basically true.

We've set up a way in which it's fun to watch the gladiatorial nature of man versus shark, so therefore we get good lipstick out of it.

So yeah unfortunately there are a lot of sharks that are killed like 100 million a year and that's why we're doing a lot of things for conservation of like all right guys we're killing sharks way faster than they can replace themselves because they they grow slowly they take a long time to mature and so we don't want to to take them out faster than they can replace themselves so there's all kinds of conservation and stuff that goes into that where we're monitoring monitoring the stocks and we're doing things like assessing their their population sizes and we are trying to put regulations in place of like there's not a lot of these types of sharks left you can't fish for these types of sharks um so

we're definitely moving a lot into the regulation but i think a lot of it is like what you're saying we have this negative perception of sharks which is unwarranted because they're just living their lives. And we therefore feel like we can do whatever we want to the sharks versus like a dolphin. That's like, everyone thinks it's all cute and whatever, but really they're like the same. One's a mammal, one's a fish, but they are both apex predators.

They both have sharp teeth. They both are really good at what they're doing, but we've decided that dolphins are cute and sharks are scary. So we can kill sharks.

Right.

So if you, if you drag a dead shark, onto the beach and say, look what I killed on my boat. People say, wow, that's cool. If you dragged a dead dolphin, say, look what I killed, people would ostracize you.

Yeah. So a lot of- This is speciesist.

Yeah.

Or what's the word? Speciesist? What's the word?

You're a speciesist.

Species, species.

Yeah, you're being speciesist, yeah.

Yeah, definitely.

So that's why- You're racist, you're speciesist.

We're working so hard to change the perceptions that people have of sharks and- And trying to show them like, okay, there's a lot of benefits to sharks, especially the ones that are apex predators. They're maintaining balance in the ecosystems. They're really important. Sharks aren't out to get you. They're not like hunting you down. They're not really even worried about you. And yeah, it's just people are really afraid of getting bit by a shark. Which, yeah, sucks to get bit by a shark. But the chances of that happening are very slim. The chances of getting bit by a dog, however, are very probable. And we bring them into our houses and we put cute outfits on them.

You're going into specious territory right now. You be careful. You be careful. Well, some people like pitfalls. I don't know. That's what I'm saying. If you put a pitfall in your house.

Some people like anacondas. That's just what they.

Can't we just all be equally afraid of animals at the same level? I'm afraid of sharks. I'm afraid of pit bulls. I'm also afraid of dolphins. I'm afraid of cats. I could be afraid of everything on an equal level.

Yeah, you should be concerned about all animals. All animals have the possibility to injure you. Just give them their space and don't make them mad.

All right, we got one more segment coming after this break on StarTalk. We're back on StarTalk. And where we left off in this shark edition of Cosmic Queries is Jasmine tells us that we shouldn't kill sharks unless we want to make lotion out of them and then it's okay.

That is not what Jasmine said.

That's not what she said.

That's what I heard. I heard that too.

I heard that. I swear. I swear that's what she said. No, no. We need to understand how they fit into the ecosystem and not be so speciesist about what animals are cute and which animals are not.

There are some cute sharks out there. Everybody Google a picture of an epaulette shark. They're adorable. Adorable.

The word adorable and the word shark appeared in the same they have.

Little they have little fins and they walk they're super cute also bonnet heads are adorable they look like they have little bonnets on their heads.

Take it from jasmine she has she has picked up and held so many sharks.

She's picked up sharks okay all right all right so let's let's keep this going.

You know i got something from uh facebook joe clopp He wonders, given the fact that sharks are neither born live or hatched from what we would normally refer to as an egg, what does baby shark do, do, do, do, do, do, do?

I didn't know any of that, so could you just catch me up on this, please?

I want to clarify something. So there are sharks that are born live. It's not like a placental birth, like a mammal, right? But yes, there are sharks that are born live. There are also sharks that come from eggs, but aren't like chicken eggs. They're like little leathery looking little pouches that are sometimes called mermaid purses, which is an adorable name. But yes, so baby sharks, what do baby sharks do? They just try to survive because sharks don't have parental care. So like you are born and you are on your own. Whether you're born live or you hatch, they'll try and lay their eggs in a place where they're like, this feels like a good spot.

I feel like my kids are going to have a chance here. And then they're just like, bye kids. And then the sharks that give live birth, you know, they like pop them out and the sharks swim away and they're like, cool, my work is done.

Wow. So mammals have very few births per species. litter. And so how many, how many possible sharks can come out of a one egg laying session?

So that depends on the shark. So there, there are some sharks that give live birth and they only have And that's usually because they just, the one that develops first, just like eats the rest or ingests the rest of them. And it's like, cool, thanks for the nutrients.

Jordan, did you hear that euphemism? It ingests them. It doesn't maul them in their sleep. No, it ingests.

I get what you're throwing down.

Yeah.

Okay. Ingest them.

Yeah. And then there are some, there are some sharks that might have very large litters, uh, like 20 or more, but it kind of really just varies between the different sharks of how many they're having. Um, and even within species, there's, there's often a range.

Okay.

All right.

So, so what, so we, in, in mammals, there's their mammary, um, mammary food for them. What, what's the first thing a baby shark eats?

So for the ones that are cannibalistic, they're siblings.

For the ones that are not, yeah.

It's a Shark Age shark world.

You know what? And you want us to not be afraid of sharks?

They eat their own siblings.

Yikes!

The parents drop them off and are like, you're good, eat your brother.

Well, usually the- If your little brother's annoying, just eat him.

The eating of the siblings usually happens inside the mom. So the mom doesn't even see the other ones.

That's worse.

I don't know. That's worse. That's worse. She said that like, no, it's different. It happens inside the mom.

That's an entire family working together to eat one of them.

Yeah. I mean, that's what happens. And then the rest of them, usually it's yolk. So they'll have a yolk attached to them, a yolk sack. That's their nutrients. And then once that's gone, usually they, you know, they've developed enough where they can hunt on their own. And so, yeah, so usually it's, they're either cannibalistic or they have a yoke.

Man, that's a tough life. I'm staying on land, by the way. I'm not going to be one of those that goes back in.

It feels much safer here.

Jordan, give me another one.

Yes. We have here from Zenzino Ferrara from Facebook. Since we know our moons have influence on tides in our oceans, there is some kind of influence by the moon in sharks' lives.

Oh, interesting.

As in the zones they choose to live in our oceans. And all the best to you guys. I hope you stay safe.

Excellent question. Thank you for that. Yeah, so Jasmine, tell me about the astronomical influences on shark behavior.

Yeah, so that's something that a lot of sharks actually, we think that their migrations are actually triggered by moon phases and things like that.

Only if they're Sagittarius. And then there's.

A lot of, obviously the tides and the moon are really, really connected. And so there's a lot of sharks that move with the tides looking for their prey. So they'll- Could.

It be that, because when the tide goes out, deep water becomes shallow and certain fishes become, if not entirely stranded, they certainly can't escape to safety. Would a shark risk getting stranded itself to go on shallow tide waters?

Yeah.

So, so sharks go into shallow areas and then there are some sharks that can handle, um, lower salinities. And so they'll actually swim up into the rivers with the, with the tides and, um, they get everything that's like coming in because they're, they're like, oh, okay. The tide is changing and their food is kind of moving with the tides. And then they kind of get funneled into the mouth of this river because there's only one way for them to go. And then the sharks will be like, ha ha, smorgasbord. And they just sit there at the mouth of the river and they're just like, I'm going to eat everything.

So the sharks took Astronomy 101. They know about tides and estuaries and brackish water versus fresh water. These are intelligent sharks. They are evolving intelligence the way that earlier question had inquired. We'll find out. In another million years, they'll be running the world.

It's coming right from the horse's mouth there. You know, Neil. Now I'm afraid of rivers. I thought rivers were safe. Now you're telling me sharks are sneaking up there as well.

Yeah, this is a very depressing session.

Here with Jasmine.

Yeah, there are some sharks that can handle lower salinity waters for short periods of time. Bull sharks are the most famous of these. They can go up in the river and then they'll come back. They have some special adaptations that help them maintain balance even when they're in lower salinity waters, which is super cool.

All right. Time for a few more.

Yep. I got one from Twitter. Nathan Warden. How exactly do sharks smell blood in the water and what is the real range of that smell?

Oh, I like that.

Yeah. How fast can blood travel in water anyway?

So blood doesn't travel very fast in water. So you know how, so there's this myth, but like, oh, you have a drop of blood, a shark is going to smell it from a mile away. And I'm like, that's not how molecules move. It has to dissipate. It's going to take a long time to dissipate, just like If you're on one side of the room and someone farts on the other side, and there's like this wave where everyone across the room is slowly smelling it before you get it.

In sequence, in sequence.

And you're like, ooh, there's a bad smell coming, but there's no escaping it because you just see everyone reacting to it. That's just how smells dissipate in the air. The same thing happens in the water. So it's not like there's a drop of blood and all of a sudden, a mile away, the shark is like, oh, there's blood. No, it has to dissipate. And in actuality, that's way too diluted at that point. A mile away, it's gonna be too diluted for them to actually detect it. The most sensitive sharks, it would probably be more like a quarter of a mile before it gets to the point where it would be too diluted for them to be able to detect it.

Plus, if they're ocean currents, they wouldn't be able to smell it upstream. They've got to be downstream from it.

Yeah, there's all sorts of things that need to happen. It's not like, oh, you have a drop of blood and suddenly all of the sharks in the world are just descending upon you. That's not how it happens. Also sharks aren't interested in the smell of human blood because they don't eat humans. Like they would, they would smell it, but it wouldn't, they wouldn't react to it. Um, now if you have a bunch of fish bleeding, yeah. Okay.

Then they're going to come check it out. But if it's, if it's a human's blood, that that's not something that they're cued into because that's not what they eat. Um, so they would, yeah, they would smell it, but they wouldn't be like, oh, that smells delicious. Let me go snack. That's not going to be their reaction.

Hmm. But if I've had like fish oil pills that morning, I cut my finger on a Bud Light and I go into the water, how nervous should I be?

You should not be nervous. Do not be nervous.

Drink and swim away. Okay.

You would be fine.

So just time for like a few more. Maybe we can do a lightning round. Let's try it, Jordan.

This is from Mike Irish 85 on Instagram. Studies have shown that low frequency sound pollution possibly have negative effects on animal behavior in the ocean. Do sharks show up in these studies? And what are the effects?

Ooh, nice one. So like the rumble of a cruise ship rotors. I mean, the propeller blades. Yeah. So what do we know about that, Jasmine?

Yeah, there have been studies where they played sounds underwater and had baited cameras. And there was less shark activity around the baited cameras when there were artificial sounds played. So it does affect them.

Baited, you mean it's got food for them, so they might want to come to the food. So this is a good experiment to see if the sound is so bad for them that they'll forego the food.

Yeah.

Wow.

Okay.

Okay.

But no one cares about the sharks.

I care about the sharks. I care about the sharks.

You care. Okay. So no one except Jasmine cares about sharks. Okay. Jordan, good quick answer.

This is from Amir John Skur on Instagram. Are great white sharks really afraid of dolphins?

It's more like a competition thing. Not necessarily fear, just like we're eating the same things. And if you're here, then I have to compete with someone. So I'm going to go hunt somewhere where there's not anyone competing with me.

Okay. That's good. That's the smart thing to do.

Yeah. Work smarter, not harder. That's the motto of the sharks.

Okay.

It's not eat your brother if things don't work out.

Oh man, I should not have mentioned that.

I'm not going to shake that for years.

And to be clear, that question was a gimme. That question was about a baby shark. That was about a children's cartoon. And you were like, you should talk about childhood cannibalism. Here's another fun one. This is from Joe Placebo on Instagram. Are the Greenland sharks really over 500 years old and what makes them different from other sharks?

Yeah. How long do sharks live?

So yeah, okay. So the Greenland shark's age is a topic of discussion among scientists. So people say 400 maybe, but like, we're just, yeah, around there. At least we've got it close. So yeah, they live a long time.

Wait, wait, wait, wait, wait. We didn't even know Greenland existed 400 years. No, I don't know when it was discovered, but we can't have possibly had good data 400 years ago to age date a shark from 400 years ago. How do we know this?

Yeah, so there's other ways to do dating. You can do carbon dating. You can look at the calcification on vertebrae, because they'll have rings.

Oh, dead sharks.

Yeah, dead sharks.

Dead sharks.

They're not asking the sharks how old they.

Are, no.

Right.

That's happening. A modern shark.

The census is hard enough to get everybody to comply in America. Let alone Greenland sharks. Good luck getting an accurate count.

Then how many people are in the household? Well, I ate them.

Do you have any siblings? That's a difficult question for me to answer.

Yeah, Junior used to live then, but not anymore.

Yeah, we used to. Let's see, at the beginning of the year, there was three siblings.

Whatever happened to Junior?

He was my brother. Now he's just indigestion.

So is it true that sharks just keep growing their whole lives?

They do. They have what's called indeterminate growth, which means as long as they're alive, they will keep growing. Obviously, it slows down when they get older. But yes, they do keep growing. So the bigger the shark, the older it is.

Wow. Okay. But the jury's still out on exactly how old the Greenland sharks might be.

Yeah.

But hundreds, clearly.

Hundreds, yeah.

Yeah.

You know, we have some specimens, but like I said, we can't ask all the Greenland sharks. So whoever you've sampled, that's like, okay, we found a Greenland shark that's this old, but there could be others that are older. That one could be the exception and not the rule.

It could be Jordan's uncle.

Yeah, it could be Jordan's uncle.

He's going to survive forever.

So we've got to actually bring this to a close. Let me just offer a reflection here. Based on all I've gleaned in this conversation, Jasmine, thank you for these enlightening points. I just wonder if climate change continues and we keep destroying the whale population, because whales are not, you know, I don't know how much they're coming back, that could take away part of the What's the term you use for who's at the top of the food chain?

You had a great term for that.

Apex predator.

Apex predator. So then the shark has, there's nothing topper higher than the shark, right? Then we go extinct on land. And then the shark figures out it could come out of the water and go on land. And so if we come back in, you know, a million years, it won't be planet of the apes. It'd be planet of the sharks, right? And the sharks would be like town mayor and the police. And somebody needs to write that story.

And in the sixth iteration of it, I know who's going to play Merlin.

I'll be there if you need it. Jasmine Graham, thank you. This is your first time on StarTalk, I think.

It is.

Yeah, well, thank you. And sharks are perennially interesting to so many people, myself included, and I think maybe Jordan. Um, so we'll try to have to get you back on and cause I'm Jordan, how many questions did we not ask? Cause we ran out of time.

There were, there were a ton. I got, I got 10 more pages of questions to pages.

Okay. So we'll hold on to those pages. So, so Jasmine, again, you co-founder of minorities in shark sciences. And so we'll see, see more people of color in a field that historically we've never seen anybody of color. And you're also a project coordinator of the Mote Marine Laboratory and Aquarium. Very cool.

So you're in it. Stay with it. Stay healthy. And Jordan, what's your latest project? When you're not interviewing Trump supporters, what do you do next?

Well, you know, I'm following the campaign with The Daily Show and I'm about to become a father real soon. So that's my next big project.

A first-time father?

First-time dad.

Oh, wow. Yes.

So I'm going to get to know that baby shark.

I would recommend not introducing your child to baby shark. You will never hear the end of it.

I'm going to take that. That's advice from an expert. I'm going to take it.

Jasmine, delighted to meet you. Jordan, always good to have you. I'm Neil deGrasse Tyson. You're a personal astrophysicist. Signing off, as always, by bidding you to keep looking up.

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