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[piano intro] - Hi there.

I'm Frank Graff.

How finding a tooth can help scientists learn about an extinct species of shark, saving North Carolina's iconic woodpecker, and finding gold in them there hills.

We're talking discoveries, next on Sci NC.

- [Narrator] Funding for Sci NC is provided by the North Carolina Department of Natural and Cultural Resources.

[calm music] ♪ - Hi, again, and welcome to Sci NC.

We've all seen the images.

Sharks have a lot of teeth, it's safe to say.

And most sharks have five rows of teeth.

They can have as many as 3000 teeth at once, and that's a good thing, because sharks can lose hundreds of teeth in a lifetime.

And it turns out, those teeth tell us a lot about sharks.

Science producer Michelle Lotker explains, that's how we know about Megalodon, a shark.

that's no longer around.

- [Michelle] Right now, we're a hundred feet underwater off the coast of North Carolina.

[garbled underwater speaking] That may just look like a pointy rock, but it's actually a multimillion year old Megalodon shark tooth fossil.

- Yeah.

So here in NC, this is, this is Meg country.

I mean, this is, you know, one of the top spots on earth for finding Megalodon teeth.

Megalodon is probably the most famous extinct group of shark and they are extinct despite what some sci-fi movies may have you believe, there's no chance that Megalodon is still hiding in oceanic trenches anywhere.

It's clear it was a carnivore.

It's clear it was a predator.

You don't have, you know, giant steak knife teeth with serrated edges if you're not eating meat.

So they were these extremely large, probably the biggest macro predatory sharks that ever lived.

Megalodon has to eat a metric ton of food every day.

That's like having to eat your Ford F-150 every other day.

- [Michelle] To learn more about how Megalodon lived, paleontologists turned to fossils.

But for sharks, the fossil record is a little different.

- One of the big differences between sharks and other animals is that they have no bones.

Their bodies are composed of cartilage, which is like a styrofoam frame for the body.

It's strong, it's bendable, but the second that they die, those cartilage prisms, they just detach, and everything disintegrates.

- The only really hard part of a shark is the teeth.

Teeth are really, really good at fossilizing.

- [Michelle] And sharks lose a lot of teeth during their lifetime.

- It's been estimated that sharks can lose as many as 35,000 teeth during the course of their lifespan.

When I die, if hopefully I enter the fossil record, I only have one skeleton to give.

Shark's teeth are constantly being lost and constantly being replaced.

So because of that, we have an incredibly rich, incredibly dense fossil record of sharks teeth, but that's it.

We don't have the bodies.

We don't have the rest of the skeletons for the most part.

And Megalodon, certainly, we don't have jaws of Megalodon.

It's all reconstructed.

The jaws we have at this museum, teeth are real.

The jaws are reconstructions.

Basically all that we know is based on this tooth record.

- [Michelle] One of the best places in the world to find Megalodon teeth?

You guessed it.

North Carolina.

- Now, is that a result of prehistoric North Carolina just having been swarming with Megalodons to the exclusion of other places?

No.

Megalodon was a globally distributed species.

We know it was living in oceans, probably mostly in equatorial regions around the world in the late age of mammals.

The reason that we are so rich in Megalodon fossils has to do with basically the peculiarities of geological history and the biases that go into our view of the fossil record - [Michelle] Fossils aren't easy to find.

A lot of the fossiliferous rock in the world has been destroyed and existing fossils are often buried deep underground.

- So you need to have rocks of the right age that one, still exist.

Two, are exposed at the surface, and three, are the right kinds of rock, because if it's like igneous or metamorphic rock, you're not gonna get fossils in there.

If you're looking for a marine animal like Megalodon, it needs to be marine sediments.

- [Michelle] And coastal North Carolina checks all of the boxes.

- There are two major sources of Megalodon fossils in the state.

The biggest one historically was these giant phosphate mines out east near Aurora.

For a lot of the 20th century, these were accessible to fossil hunters in the public, amateur fossil collectors, as well as to paleontologists.

- [Michelle] The layer of rock the mine is targeting is from the nearshore marine environments where a lot of biodiversity occurred, so it contains a dense concentration of marine fossils.

And mining accelerates the rate of new fossiliferous rock being exposed.

But there's another natural process that unearths fossils in coastal North Carolina.

- A lot of this Megalodon-bearing rock is not at the surface but just below it.

And so how can we get at it?

Well, natural waters get at it.

- [Michelle] Rivers like the Tar and Cape Fear cut through this subsurface rock, washing out fossils and redepositing them on the river banks and beach.

- That rock is also exposed as you get the drop off, off the coast.

And so wave action on the coast is eroding the edges of those fossiliferous layers, which we call the strata and washing them then into the oceans.

It's basically, it's the right combination of factors to have lots of Megalodon teeth where we as humans can get them.

- [Michelle] Remember that diver who found a fossilized Megalodon tooth earlier?

That was captain Shane Gaither who lives on his boat in Carolina Beach.

- Here in our inlet, as you're going out to the ocean on the bank there's actually a clay ledge at low tides you can see, and it looks just like the ledge is underwater.

- [Michelle] Skilled divers like Shane head out to these eroding underwater ledges to find shark teeth and other fossils.

- There's a lot of different conditions you can find shark teeth while scuba diving.

Where we are in North Carolina, it's typically pretty far offshore and on average a hundred feet of water.

So it's not for the novice diver.

It's very rare that you see a whole tooth laying exposed.

You know, it's typically, pretend my thumb is black.

That's all you see of that tooth, but that sixth sense kicks in and you investigate and you fan and [makes whooshing sound] tooth.

Let's see what we got.

So we got at least one really good one.

That is a Megalodon.

You'll clean up nice.

This is a broad tooth Mako, kind of a we call that a Fragalodon, fragment of one.

- [Michelle] Since fossils are the only remnants of Megalodon we have.

Studying them helps researchers understand more about these massive ancient predators, like what they ate.

And fossil donations to the museum allow for new discoveries.

A donated Megalodon tooth with a unique split down the middle expanded our understanding of what Megalodon might have eaten.

- On most Megalodon teeth right here in this surface right here, it's curved, it's convex, or it's flat, but on this tooth, and if I can get the lighting right, you can maybe see it goes in right there.

That makes us think that whatever caused this deformation, it started early on at the base of the tooth when it was still forming.

- [Michelle] Historical illustrations of similarly misformed shark teeth helped Haviv come to the conclusion that the trauma was likely caused by something spiky that the Megalodon ate.

- [Haviv] It would make sense that they weren't just eating whales, but they probably ate a plethora of different animals.

If they found a meal, they were going to eat it.

They had to, because they had to eat a metric ton every day.

- We are reliant on partnerships with the broader community of anyone who is out there looking for fossils.

As a state paleontologist in North Carolina, I can't be at every river cut every day, where there was a rainstorm and maybe a new fossil washed out of a river bank.

- And so donations like this are really vital towards allowing us to share with you and unravel the mysteries of our natural world - Now to discovering a bird that is difficult to spot but you can definitely hear: the red-cockaded woodpecker calls North Carolina's Longleaf Pine forests home.

Trouble is, as science producer Michelle Lotker explained, these endangered birds need old living pine trees to nest in.

And those trees are hard to come by.

- Today, we are in the beautiful Sandhills game lands.

We are here to basically find some red-cockaded woodpeckers.

So we call this device a peeper pole.

And what it does is that we have a camera up here.

This pole extends until it reaches the cavities.

Once we have it in there, it will allow us to see what is inside.

- [Michelle] Lauren is part of an extensive team of researchers monitoring the endangered red-cockaded woodpecker in the Sandhills of North Carolina.

- So I see three nestlings.

Round day 20 I'll be able to come back and specifically see how many have a crown patch or not, and that will tell me how many males and how many females I have.

- [Michelle] The data Lauren collects on this nest and others will be added to one of the longest ongoing vertebrate studies on the planet.

In the early 1970s, the red-cockaded woodpecker was listed as a federally endangered species.

- When monitoring began in 1980, population levels in the Sandhills were relatively low.

- [Michelle] Red-cockaded woodpeckers are in the Sandhills because of the Longleaf Pine forest - [Brady] Red-cockaded woodpeckers are unique species in that they excavate their cavities in live old pine trees.

- [Lauren] Specifically the Longleaf Pine is one of the sappiest pine trees out there.

And that's great for the RCW because they use the sap as a defense mechanism.

They will drill resin wells into these trees which will flow with sap.

Their biggest predator is the black rat snake.

What the rat snake will do is it'll try to climb the pine tree, it'll get sticky with sap, it'll fall to the ground, and it'll be sappy for a few days.

- [Michelle] To gather data about red-cockaded woodpecker nesting success, Lauren also climbs these sappy trees, fortunately with the help of ladders and some other specialized equipment that helps her take baby birds out of the nest to add some fancy jewelry to their legs.

- So we have our pullers, helps us pull out the nestlings.

Oh hello.

Hi hi hi.

So once we pull the nestlings, we wanna check in the cavity to make sure that we got 'em all, to see also if there's any eggs present, come back down the tree, band the chicks.

So each group of birds has a specific band combo.

We call it a clan combo.

So they have two bands: an aluminum band and a color band on their right leg.

And they have three bands on their left leg.

Once we band them, we wanna get a weight on them.

So we put 'em in a little weight bag, get a weight.

And once we do all that, we climb back up the tree, put the chicks back in.

We try to do it butt first, and we try to do it with the heaviest chick first, cuz if we have a lighter chick that way, they might get you know, the next bug that's coming in.

We take our mirror and our light back out, put it back in, make sure that they're all down there, safe and sound.

And we climb back down the tree.

- [Michelle] The colorful bands stay on the birds as they grow and allow researchers to follow specific birds as they leave the nest or fledge.

They use high powered scopes to spot the tiny leg bands.

- Here they come.

Incoming.

Is that orange aluminum again?

Big babies.

Oh, there's number two.

That was dark green on the right.

- Yes.

So each cluster has their very own band combo.

That's how we tell them apart.

And each individual has a different color band on either leg - Just two adults so far.

- So far, looks like a third adult aluminum over red.

- Cool.

- So we've counted three adults here so far.

- [Michelle] There are more than just one pair of adults around this nest, because red-cockaded woodpeckers are cooperative breeders.

- [Lauren] So they have a very unique social system.

They live in these family groups, which are made up of a breeder male, a breeder female, and what we call helpers.

- [Michelle] Helpers are usually male, and they assist with everything from incubating the eggs to defending the territory, all in the hope that they might one day inherit it and have their own nest.

For a Longleaf Pine tree to be the right size for a red-cockaded woodpecker nest, typically it needs to be about a hundred years old, which can be hard to find.

- Historically through logging up until the beginning of the 1900s, almost the entire Southeast was clear cut for railroad, boat-making any number of things, turpentine.

So now we're, say a hundred years post that main clearing in the Southeast, we're getting a lot of trees that are coming into perfect age and internal structure where the birds can make their own natural cavities.

To make a natural cavity, these birds have to excavate through the bark, a thin layer of cambium, the sap wood, and then excavate a cavity that's maybe three inches around by seven inches deep in the heartwood of the tree.

And that can take anywhere from one to 12 years to make one cavity.

- [Michelle] One solution to help populations grow more quickly?

Artificial nesting cavities.

- This is an artificial cavity.

It's one of the most important tools we have for bridging the gap between a younger forest that may have bigger trees and more of an old growth state where the birds can create their own cavities.

This is installed in a large tree with a chainsaw and the birds will take to these almost immediately.

I've put them in before and had them use them that same night.

They've been a crucial tool for getting us to this point in our recovery journey.

- [Michelle] And it's an ongoing journey, although populations have improved significantly since the 1970s.

- Since then, we've had really great conservation successes by growing the populations where we can do prescribed fire and artificial cavity work, but they are what's considered a conservation reliant species.

And that all the work that we're doing is gonna need to continue to happen going into the future.

- [Michelle] Fire maintains Longleaf Pine ecosystems by clearing out the understory.

Unique species in these forests, like this wire grass, are specially adapted to rebound quickly after a fire.

As work continues to be done to maintain their habitat, researchers like Lauren are starting to ask questions about how these birds will adapt to a changing climate.

- Climate change research on the RCW is just sort of ramping up.

There have been studies that have seen that there is a climate-induced shift in nesting earlier.

With this climate-induced shift, we are seeing this increase in hatching failures and brood reduction.

- [Michelle] Brood reduction means less chicks survive from each nest.

Based on the trends they're seeing further South, researchers are worried populations in the Sandhills will be impacted next.

- [Lauren] It all goes back to the pine trees.

They have to go where the living pine trees are.

It's looking at that and where the climate change is impacting them.

They sort of, kind of don't have a choice, because this is their home.

This is, they're endemic to this ecosystem.

We just have to keep doing what we're doing with the monitoring and the management.

And just keeping up the ecosystem of these birds.

- Here's the ultimate discovery.

Think how excited you'd be if you walked down the street and found a gold coin.

Now imagine walking along a stream and finding a rock of gold.

NC Culture Kids picks up the story.

- Hey, everyone, Emily here.

Most people think that gold was first discovered in the United States, somewhere maybe in California or even in Georgia, but they would be wrong.

Gold was first discovered here in North Carolina right along this river right here.

What?

- [Camera Person] Creek.

- Oh, all right.

One more time.

[calm music] ♪ Here to tell me all about it is site manager for Reed Goldmine State Historic Site, Larry.

Larry, thank you so much for having me here.

- Glad y'all can crank it out today.

We're actually standing here at Little Meadow Creek and this is where in 1799, 12-year-old Conrad Reed along with his siblings decided to go bow and arrow fishing in the creek.

Conrad found this interesting, shiny rock.

[old-timey music] It was rather large and rather heavy.

We'll leave it on the front porch, maybe use it to prop the door open.

[slide whistle] [old-timey music] When he took it to Fayetteville, they found a jeweler who knew exactly what it was and asked John Reed to name his price.

Well, John thought about it, and he thought about it, and he finally said $3.50.

- What?

- For today, that's not a lot of money, but for John in 1802, that was roughly a weekly profit for his farm.

- Oh, okay.

- So he figured for what he thought was a supposedly worthless rock, that should be a fair offer.

- Yeah.

For a door stop.

- For a door stop.

Problem is what Conrad actually found was a 17 pound gold nugget.

- Wow.

- The value of the gold in 1802 was around $3,600 - At that time?

- At that time.

So John Reed was only paid one tenth of one percent of the actual retail value.

- Oh my goodness.

- So the density of gold is actually twice as heavy as lead.

We'll allow it to sink straight to the bottom and stay there and allow us to remove most of everything else in the pan.

And then we'll possibly be able to find it.

- Oh, cool.

Okay.

So I'll let you go first.

Show me how it's done.

- Well, you just take the pan, place it in, now you'll notice it bubbles up.

That's literally air trapped in the dirt.

So you kind of let that bubble up for a minute or two.

- Oh yeah.

- To kinda get the air out - There it goes.

- And then you bring the pan up, drain off about half the water into the pan and then literally start shaking it back and forth.

So here as we get the mud, we just simply pour it back in the trough, dip our pan, get some cleaner water, and continue-- - Do it again.

[scraping and sloshing] Yeah, I can see this.

This water's a little more murky - And this is kind of what you're wanting right here.

- Okay.

- Now look at this.

This is one little trick.

All I'm doing is taking my hand and making kind of a flip with my wrist and I'm washing stuff out.

Now for you, if you want, take the ridges and turn 'em toward you, and then get a little water in your pan.

Start shaking back and forth, and at the same time, angle this end toward the water.

See how it's starting to move out?

That's one way you can get more of the material out faster is getting a little bit of water in, getting it mixed up.

- Larry, I'm gonna be a pro by the time we're done.

[calm music] ♪ - Everything kinda worked its way down.

I'm gonna start gently rolling this around in a circle.

The gold, if it's here, will actually stay still and everything else will move away.

- You found some!

- Let's say we have found a pretty decent size gold nugget.

All right, now, what we want to do is get a little bit more out.

Little more.

Okay.

Yes.

You are down to the nitty gritty.

So what we wanna start doing is that same process of rolling this around.

You see anything?

Yep.

She has found gold.

Now I'll admit this is closer to what people will find today versus mine.

What's your reaction to finding gold?

- I can't believe I just found this little speck of gold.

It's so interesting how, yeah, the shine, you can definitely notice it's there when you're doing the swirling.

But like you said, I notice my eyes like gravitate towards the thing.

That's not moving.

It's kinda like, what is that over here?

And then there it is!

[calm music] ♪ ♪ - So Larry, I can't help but wonder as we're making our way around the mine, how did they actually get the quartz out?

- Well, that's a good question.

They had to actually blast the quartz rock.

Dynamite was not invented until 1867.

But the way they would blast it is they had to make blasting holes to put the powder in and then a charge to detonate.

And there was a few methods to do this.

One of 'em.

I could show you here with these tools it's called single jacking.

And this is where the minor working alone would put the drill bit up against the rock and start hitting it with the hammer.

But as they would hit the drill steel, they would twist it.

So you hit, twist, hit, twist.

And believe it or not, it would take a minor working alone about 30 minutes to an hour to create a blasting hole about 15 inches deep.

Now to speed up the process, minors would what are called double jacking where they would have two of them at the same time one holding the drill bit and one holding the hammer.

- So one's doing the twisting and-- - One's doing the twisting.

So if you'd like, if you want to take the hammer, and I'm gonna take this a little bit longer drill bit.

- She's a little heavy.

- Yeah.

Strike the end of it.

Twist.

Strike.

Twist.

- They're probably much, you know throwing all their weight into it.

This thing is heavy.

[calm music] ♪ ♪ - That's it for Sci NC for this week.

Be sure to check us out online.

I'm Frank Graff.

Thanks for watching.

[calm music] ♪ - Funding for Sci NC is provided by the North Carolina Department of Natural and Cultural Resources.

[calm music] ♪