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NARRATOR: The great white shark, fearsome and fascinating.
Official YIFY movies site: YTS.MX
But is there more to these apex predators than first meets the eye?
Two scientists...
Sheesh!
NARRATOR: ...with a groundbreaking theory...
This should give us some really good data.
RYAN: I've got a shark.
NARRATOR: ...will launch an unprecedented investigation...
...to find out if these explosive hunters...
Oh, my gosh! Yes!
NARRATOR: ...can camouflage their skin, making them the ultimate predator.
Armed with over 300 gnashing teeth,
growing up to 20 feet and weighing 5,000 pounds,
and capable of speeds of over 20 miles per hour,
the great white shark has been the perfect predator for 12 million years.
In Mossel Bay, South Africa, there is a great white shark hot spot.
On any given day, we can have probably upwards
of 50 different great white sharks that are swimming in this bay.
My name's Ryan Johnson, I'm a shark biologist,
based here in southern Africa.
Two sharks here, Gibbs.
I'm Gibbs Kuguru. I'm a shark geneticist. I'm based in the Netherlands.
NARRATOR: Together, these scientists have developed
a potentially game-changing theory about the ocean's most infamous predator.
RYAN: I think myself and a lot of scientists have always been wrapped up
in the speed, the power, the size, the strength of great white sharks.
But as you look at them, you realize maybe there's something very subtle going on.
And that's when we caught on to the idea that,
"Are these sharks actually manipulating their color
to become almost camo sharks?"
NARRATOR: Camouflage is common among marine creatures.
Octopuses, squids, and cuttlefish are capable of lightning-fast color shifts,
and blending into an environment can be an advantage
to both prey and predators.
RYAN: All these other animals use camouflage
and sophisticated techniques to blend into the environment.
But sharks, that's a different story.
NARRATOR: Great whites are varying shades of gray
on the dorsal side of their bodies with a white belly underneath.
This countershading helps sharks blend in, whether seen from above or below.
But the ability of sharks to actively camouflage would be a revelation.
The theory that great white sharks can change
and modulate their color is the first of its kind.
There has been some research done on smaller species of shark,
but never in anything the size of a great white shark,
never on a predator as famous and renowned as a great white shark.
Now, proving it is gonna be massively challenging.
NARRATOR: To put their theory to the test,
Ryan and Gibbs are launching a one-of-a-kind investigation.
GIBBS: We heard just about every fisherman's tale
about these sharks spontaneously changing color.
But then you look at the literature, and you find actually there's little clues
that might show that this really is happening.
NARRATOR: Great whites can be found in cool coastal waters around the world.
And in South Africa, they are well documented.
So I got these photos from my research buddy, Dylan.
This is a massive database all through the entire South African country.
He's matched up all these fin photos from the years.
NARRATOR: The collection is comprised of thousands of sharks.
Nostalgic, looking back at these old photos.
-Yeah. You took a couple of these. -Yeah.
NARRATOR: Key identifiers like scars and unique dorsal fins
mean scientists can track and compare the color of individual sharks.
RYAN: See, this one here is massively lighter than the other one.
-This one's dark, this one's light. -NARRATOR: But the evidence is flawed.
RYAN: Yup. This is all the same shark.
The problem we had in trying to look at
whether sharks are modulating their color is the databases in the past
didn't have a frame of reference for us to be able to tell
if this shark was actually darker or lighter.
NARRATOR: Lighting conditions, weather, and even camera settings
can completely change a shark's appearance.
RYAN: If we're gonna prove that this type of color change
is actually the shark changing color, we need some type of control.
And that's when I came up with the color board.
NARRATOR: The grayscale color board will be the key
to collecting visual evidence of color change
through a range of experiments.
RYAN: It's impossible for us to accurately measure
the color of a shark in the wild. That's the beauty of the color board.
As long as I can get photographs of the color board
and the sharks together, take it back to the computer,
correct the colors,
then I can find out the exact color of that shark.
NARRATOR: These experiments should also provide clues
to the factors that motivate camouflage.
RYAN: There has been a few studies on captive species
to show that sharks can change color, and that it is hormonally controlled.
What I'm hoping to do is prove conclusively
that great white sharks can change color
and that it is related to certain behaviors.
When I look at it, it's so simple, but it's actually a stroke of genius
how this really solves the problem of, you know,
getting this, you know, color change in view.
I think that's the first time I've ever been called a genius.
I'll take it because it is rare. (laughing)
The next step is, how am I gonna get this color board
next to the shark in these different situations?
And that just takes a little bit of creativity.
-So, you got that, mate? -Alright, cool, yeah. Let's get going.
RYAN: Careful, careful, careful, careful. Keep the tension.
GIBBS: There we go.
It's gonna be exciting stuff.
RYAN: One of the most important tests that we're gonna do is the breaching test.
GIBBS: Breaching is sort of this ambush attack.
You know, they need speed, power, stealth.
RYAN: This is when we're gonna be able to measure the color
of a great white shark in its ultimate hunting mode.
NARRATOR: In the middle of Mossel Bay sits Seal Island.
RYAN: This island is the epicenter for great white sharks in South Africa.
NARRATOR: Every day, hundreds of fur seals swim for their lives...
through a gauntlet of great whites.
RYAN: The great white shark's success rate in hunting Cape fur seals
is almost 50 percent, and that's really high for any predator.
With these sharks, they've got very specific areas
where they want to hunt and patrol,
and it's usually right underneath the natural routes
that the seals are exiting and entering the islands.
NARRATOR: Ryan and Gibbs are towing a decoy seal
in the hopes of encouraging sharks to breach.
RYAN: It's about trying to capture the breaching shark
alongside a color board and being able to measure the color of that breaching shark.
NARRATOR: It's a quiet morning, but Seal Island rarely disappoints.
Oh, there's a predation! Natural predation right over there!
Oh, still going for it.
Oh, oh!
-GIBBS: Ho, ho! -This is hot-- Oh!
RYAN: This, this seal is in trouble.
GIBBS: Yeah. He's using the boat for cover.
And even though the shark missed on that first breach,
it scared that seal so much
that it's now hiding around the boat, using it for cover.
NARRATOR: The seal leads the shark right to the decoy.
-RYAN: Woo! -GIBBS: Oh, yes!
-Got it! Got it! -Nice one, man.
NARRATOR: The shark and the color board are clearly in frame.
It's the first successful breach of the experiment.
It sends goosebumps down my spine every time.
I mean, you just can't...
you can't help but feel emotional every time you see it.
NARRATOR: Sharks are here in numbers.
GIBBS: Oh, ho!
-RYAN: There we go! -GIBBS: There we go.
NARRATOR: Stalking seals...
all...
day...
-long. -GIBBS: It's having a go at it.
Woo!
NARRATOR: As the sun sets after a day of data collection,
the team hopes for one last breach.
RYAN: Hit that spot. Hit that spot.
Oh, ho!
Alright, we've lost the color board, we've lost the decoy.
GIBBS: Dang it!
RYAN: Because it's so dark, the shark couldn't even see which way to go.
He's going for it again!
NARRATOR: Sharks often hunt at twilight,
but in the darkness, even a great white can miscalculate.
-RYAN: Oh, oh, oh. -GIBBS: Dang it.
RYAN: This is gonna be an issue floating again.
NARRATOR: They'll have to rebuild before getting back on the water.
But building their database of evidence is underway.
RYAN: Just looking at that and comparing that to the color board.
Right up there, isn't it? Dark.
Science is not fast, it takes a long time, it takes a lot of data.
-Nice. -Ooh.
RYAN: Particularly when you're trying to rewrite a whole idea
on a sort of scientific paradigm.
This is money in the bank, each one of these.
NARRATOR: But there's more to this study than meets the eye.
RYAN: The behavior is only one side of the study.
The cellular work is the other side, and it's equally as important.
Yeah, it's a male. Definitely a juvenile.
NARRATOR: Ryan and Gibbs have a rare opportunity with their investigation.
So that's a juvenile.
RYAN: A chance to get to work with a great white like this
comes around, you know, once or twice in a career, for, for at least me.
First time.
NARRATOR: When sharks are tragically caught in fishing nets...
RYAN: Okay, that's good.
NARRATOR: ...scientists like Dr. Matt Dicken ensure it isn't in vain.
MATT DICKEN: One of the things we do at the Sharks Board
is collect as many samples as possible.
And that really improves our knowledge and science of this incredible species.
NARRATOR: Dissection will let the team search for vital clues
to their color change theory, hidden in the stomach of the shark.
The diets of great whites are seasonal
and change as they grow larger and more powerful.
So what and where sharks eat
could tell us something about their need for camouflage.
RYAN: It's quite tough, eh?
I want this definitive proof that these great whites
do, in fact, feed at the surface, feed mid-water, feed at the bottom.
And this is sort of the detective work you have to play
to actually identify what the animals are eating.
-MATT: You know what that is? -GIBBS: No. What is it?
-Stingray barb. -No way!
So again, I'm thinking that actually could be the real evidence you need
that these white sharks are feeding on the bottom.
GIBBS: Right on.
-Outstanding. -RYAN: Dang.
NARRATOR: This small find proves a big point.
The ability to adapt camouflage could be a huge advantage
to the vastly different hunting strategies
at the bright surface and the dark sea floor.
RYAN: Great success with the stomach contents.
You know, finding that evidence of the stingray
and that the sharks do have this varied hunting behavior that we wanted.
GIBBS: And there's a whole bunch of them, too.
NARRATOR: But the key to proving color change
is scientifically possible goes beyond skin deep.
My research is based on the skin of sharks and the different adaptations they have
that cause their skin to work in different ways.
One of these adaptations that we think they may have
is this ability to change color.
We wanted to design an experiment
that would sort of tell us if this is even possible.
NARRATOR: The secret to color change may be hidden at the molecular level,
with a little-known cell called a melanocyte.
GIBBS: A melanocyte is the tissue that sort of gives rise to pigment in animals.
It acts kind of like a circuit board underneath the skin
where it sort of flexes and contracts based on what the animal needs.
So let's say you have a stimulus from the sun,
the circuit board tells your skin to go a bit darker.
And, you know, vice versa, if you haven't seen enough sun,
it'll cause your pigment to sort of shrink in, i.e., it goes paler.
NARRATOR: To understand if melanocytes are present
and capable of changing a shark's skin color,
the team has devised a series of tests.
GIBBS: We're gonna try and take some tissue samples
of the skin of the shark and then expose it to some hormones
to see if this actually does induce a color change response.
And we're hoping that as each of these hormones interacts with the tissue,
it actually causes them to go lighter or darker.
NARRATOR: The hormones replicate those
that are believed to flow through a live shark
during behavior like hunting or resting.
GIBBS: We do have some hypotheses for what these hormones will do.
The first one, MSH, is actually a hormone that stimulates
the expansion of the melanocytes
in just about every species that has melanin.
We have the adrenaline which has triggered a paling response
in some sharks and has also created a darkening response in some fish.
And then the last hormone is the melatonin.
And we think this is definitely going to give it a paling response.
NARRATOR: If the test works, it should change the color of the skin.
This feels like a real moment of truth,
seeing how these sharks actually will respond to these hormones.
-RYAN: Ready? -GIBBS: Yup.
NARRATOR: But the samples don't appear to be changing.
I actually don't think that the skin is really reacting. It's...
Looks more or less the same.
The dead shark skin doesn't seem like it's going to work.
I think that's just because the tissue of the shark is physiologically dead.
So all the little biochemical pathways are totally shut down.
This is a new experiment.
And I think this is typical of science, that it doesn't work the first time.
Yeah, I think Ryan and I are gonna have to tweak our methodology.
NARRATOR: Most sharks are shades of gray or brown.
Some, like the tiger or zebra, have distinct patterns that set them apart.
In False Bay, South Africa, Ryan and Gibbs are looking
for a species with an adaptation as incredible... as color change.
GIBBS: Puffadder sharks are probably one of the most docile sharks.
You'll oftentimes see them
sort of nestled between two rocks or snuggling around a piece of kelp.
So they're cute.
They're not like a great white, that's for certain.
But puffadder shyshark recently has been discovered to exhibit biofluorescence.
And that means essentially it's a glow-in-the-dark type shark.
NARRATOR: Why a shark would evolve to glow is a mystery.
RYAN: They're incredibly camouflaged to the reefs that we'd find them on.
And I always wondered why would an animal
that's so focused on camouflage then start glowing?
NARRATOR: Ryan designed a specialized camera
outfitted with UV lights to observe glowing puffadders.
RYAN: Ready, buddy?
NARRATOR: Documenting them firsthand will require diving this shark-filled bay...
at night.
RYAN: Night diving is an acquired taste.
And tonight, all we're gonna have is this UV light,
which is essentially invisible to us. The rest of it's gonna be black.
NARRATOR: In the deep, dark oceans around the world,
some species of marine life have evolved not to camouflage, but to glow.
These abilities are called bioluminescence and biofluorescence.
Bioluminescence is a chemical process in which an organism generates light.
Like a lantern shark that glows to avoid predators,
or plankton glowing at the ocean's surface.
Biofluorescence... is a different and more mysterious process.
GIBBS: Biofluorescence is the ability for an organism
to take in a certain wavelength of light and re-emit a different wavelength.
RYAN: As you go deeper, all the light disappears except for blue light.
And what these puffadders seem to do
is take in that blue light, then emit out this yellow-green light
that sort of gives them this glow-in-the-dark appearance.
GIBBS: The key here is to figure out how sharks are using light
and color to be better adapted to their environment.
So we're here to explore what this does for them and their survival.
NARRATOR: Many corals, over 180 species of fish,
and even some crabs display neon colors when exposed to UV light.
Swell sharks in California also glow green
under light that mimics how they see one another.
Why is not exactly known, but many scientists believe
it comes down to enabling communication
while still retaining camouflage from predators.
RYAN: And what we think is happening is that
the shark's eyes evolved to see this yellow-green
sort of spectrum of the light.
GIBBS: This is an adaptation so they can essentially,
at night, navigate these waters undetected
from other organisms but still be able to see each other.
NARRATOR: Even as they glow to one another,
camouflage remains key to their survival, as it may be for the great white.
Biology is inherently a comparative art.
We understand more about one species by understanding how other species do it.
NARRATOR: Whether camouflaging or communicating,
the puffadder's appearance seems to be connected to its behavior.
RYAN: So there's two parts of the color theory.
One is that individual sharks can manipulate their color
and two, that their color is determined by different activities.
NARRATOR: With the color board repaired,
the team sets out in search of more great whites
to document for their database.
I know this is a resting area for great white sharks.
So the idea is to try to get this color board
next to what I think is a resting shark.
And if it is that this color is controlled by the hormone levels,
you could find that a resting shark hanging out is a very different color
to one that's motivated by hunting or scavenging.
NARRATOR: While Ryan operates a drone, Gibbs captains a remote-controlled boat.
(propeller whirring)
RYAN: Hey, I got a shark. Gibbs, I got a shark, buddy!
-GIBBS: You got one? -RYAN: I'm on a shark. (laughs)
GIBBS: Alright. Let's throw this RC boat in.
Okay, let go, let go.
-You got it. -RYAN: Go, you got to go hard, buddy.
Go hard, go fast.
-Can you see me? -RYAN: Not yet. Not yet.
GIBBS: Uh, going forward still.
-RYAN: Gotcha. -GIBBS: Yeah, I think that's it.
RYAN: I gotcha, buddy. You got it?
-(laughs) -Nice.
-RYAN: I'm just gonna bring it around. -GIBBS: Yeah.
You got me there?
RYAN: Yeah, I'm gonna bring it down lower, just so I can get the color...
There we go. So we get the color board.
-GIBBS: Nice. -RYAN: Okay, that's good.
There she is, she's up at the surface now.
-Yeah. Outstanding. -Yeah, man.
NARRATOR: A resting shark and color board are in shot.
It could provide very different data to the great white mid-hunt.
This is just one piece of a far larger experiment.
NARRATOR: To contrast with images of resting at the surface
and hunting above it, the team also needs to capture color data at depth
when sharks are scavenging.
RYAN: Color changes very quickly as you go deeper into the water column.
The reason why I'm so interested in doing the experiments down deep
is because how a shark would camouflage itself
at the surface is very different
to how it would camouflage itself at the bottom.
NARRATOR: Ryan will be lowered over 30 feet in his custom dive cage.
Come on out, and let's get this cage down there.
We lost the GoPro zoom. It's gonna be in the cage.
Oh, she's gonna go right for the cage. Nice.
The purpose of this whole, you know, attracting sharks to the boat
was to get them close to the color board.
Another shark. Drew, look at her diving down there.
RYAN: When you are down deep there,
you don't know if what you're seeing is actually accurate
because the light has degraded so much, and the visibility is so bad.
So that's why it's really essential that we have that color board,
and we can capture the shark and the color board together.
'Cause then I can take it back, correct it,
and work out truthfully what the color of that shark is.
Now she dives down. These sharks are giving us plenty of data.
NARRATOR: It's a rare glimpse into the great white's deep-water world,
where they scavenge for rays and other prey.
RYAN: The whole setup worked well. What was striking me was the camouflage.
It is the camouflage that makes these sharks successful.
That ability to blend into the environment,
and that environment down there, it's, it's monochrome.
-Hey, you work for it. You work for it. -Yeah, sure.
NARRATOR: With their database nearly complete, Ryan and Gibbs are finally able
to turn their research further afield to reports from a remote part of the world
and another unique shark skin adaptation.
GIBBS: As part of our investigation on sharks and color,
we're looking for another species of shark
that may actually be able to change their color for the sake of camouflage.
NARRATOR: Species like the wobbegong and angel shark
use unique skin patterns evolved over millions of years
to camouflage into their surroundings.
But sharks with changing skin patterns are rare.
A study in the Maldives investigates
whether a genetic condition is causing one species
to exhibit this uncommon adaptation.
GIBBS: We are here in the beautiful, sunny Maldives
in a place called Baa Atoll
looking for a very rare type of blacktip reef shark.
NARRATOR: Tropical reefs are hot spots of life and adaptation.
While some creatures try to stand out, others do all they can to blend in.
Could this unique case provide clues to how great white skin might change?
My perspective on what brings great whites close
to these blacktip reef sharks is down at the molecular level.
This report came out a couple years ago, and it had these images of these sharks
that had developed this weird spotted pattern.
And I think this might be caused by a genetic disorder called leucism.
Leucism is a genetic trait that's caused by the malfunction of the melanocytes.
So when it stops working properly, we start to see this patchy distribution
where melanin pigment in the shark is lost.
NARRATOR: Gibbs is using methods both old and new...
seeking photographic evidence and genetic samples of leucistic sharks.
But is this condition an unfortunate aberration or possibly rapid adaptation?
This genetic disorder of leucism is like a freak accident.
It might have the exact key these sharks need
to be camouflaged better in their environment.
If these blacktip reef sharks are actually able to camouflage,
it really means that these sharks have somehow or another
found a way to actually live around the human impacts of climate change.
And I say this because the Maldives has actually experienced
quite a bit of negative impacts from climate change.
Sea surface temperatures have been above 30 degrees,
and that's caused the corals to bleach. So when you see the coral reef,
there's a whole bunch of dead corals mixed in with the living corals,
and that makes the environment have this random scattered pattern.
And I think these sharks might actually be blending in better
in their environment than the other sharks
that haven't developed this genetic disorder.
From the report, we found that these sharks
that have the leucism are all juveniles,
which makes me think that either these sharks are surviving
and growing out of this skin pattern, or maybe this genetic disorder is lethal.
But all we would need is proof of just one subadult animal
with this trait to say that actually there is a chance that they are surviving.
The Maldives is a perfect place to find these blacktip reef sharks.
Unfortunately, they are very skittish.
-Hey, Ryan, how's it going? -RYAN (over video): I'm doing well, man.
I'm curious, very curious how it's going in Maldives.
Have you managed to be able to catch the sharks,
do the genetic samples, anything like that yet?
I haven't been able to get my hands on these sharks.
Unfortunately, it's, it's a bit more challenging than I expected.
But we did manage to get one leucistic blacktip reef shark in plain view.
So that's, that's something.
Do they actually blend in?
GIBBS: I would definitely say that their random pattern is matching
that random pattern of the coral reefs. And unlike the smaller ones,
leucism is actually presenting itself a little bit less.
It's almost like these larger ones are growing out of it.
RYAN: Wow. The zebra shark does exactly that:
as they grow up, then they change their color.
NARRATOR: Like the zebra shark,
this group of blacktips could be morphing their skin pattern
as they grow and become less vulnerable.
And while any heightened camouflage
seems to be connected to melanocytes in the skin,
leucism appears very different to any rapid hormonal change
affecting the skin of great whites.
Whilst we are seeing some color aberrations,
I don't think this is exactly what I was looking for when I came out here.
RYAN: Now, I've been thinking more about the great white
and the skin sample test and the hormone test.
We didn't get the response.
I want to know more about this and whether we got a solution.
Clearly, the dead cells didn't work.
So I would suggest that we get back out there
and collect some of this live tissue from the great whites
so that we can actually get these cells to change in real time.
NARRATOR: While the team prepares for a final attempt to collect live samples,
Ryan begins to crunch the numbers
on his color board database for the first time.
We've put the color board alongside the cage diving boat
where we can see a shark that's in a scavenging mode.
We've also taken the color board down to the bottom of the ocean.
And then we've also looked for resting sharks.
The most exciting experiment, but the most challenging,
was getting the color board next to breaching, hunting great white sharks.
In this type of behavior mode,
these sharks need to maximize their camouflage.
If we can match up the sharks in different experiments,
we can see whether those sharks, in fact, do change color, and then secondly,
how that color relates to the different activities.
NARRATOR: The first step is to identify images of an individual shark
that were captured in various experiments.
RYAN: The idea is that we sort of build up the identification of the shark
over different images, over different situations.
And now I've got one shark, this shark with a very distinct abscess
on a jaw that we've been able to see in multiple locations.
NARRATOR: Ryan carefully adjusts the images
so the grayscale color boards are matching in every shot.
RYAN: The goal is adjust the square here to get true white.
We can adjust this square here to get true black.
Once we've done that, we know that every pixel in that frame
is exactly correct.
NARRATOR: Once calibrated,
Ryan can then isolate and analyze
the color of the shark in different states of activity,
assigning their skin shade a numeric value.
RYAN: One being very dark, almost black, 100 being very white, almost pure white.
We can't always get the entire shark's body into frame,
but we can work with certain parts of the shark's body.
So we've got it here.
We've got the breaching, hunting shark scoring a score of around 22,
which is a very dark color
versus here, the same shark is around the boat,
and it's scoring around 54, 53.
So, clearly, light coloration, dark coloration.
Is it at the stage where we can make big conclusions? No.
But what it has proven is that this individual shark
has the ability to change color.
And over time, we're gonna be able to build up this database
and work out how individual sharks can change their color
and whether the color that they adopt at any given time
is related to what activity they are involved with.
NARRATOR: It's a satisfying result after months of field work.
But the next stage of the investigation will be crucial
to proving that great whites really are camo sharks.
RYAN: Second, we're gonna switch to the molecular level.
And that is getting live samples from the great whites,
getting them down to the laboratory and analyzing them under the microscope.
We're gonna be able to answer once and for all
whether these great whites can, in fact, change their color.
(birds squawking)
NARRATOR: Gibbs and Ryan have an ambitious plan
for one final molecular test.
The behavior is only one side of the study.
The cellular work is the other side, and it's equally as important.
NARRATOR: But this time, they'll need a skin sample from a live great white shark.
GIBBS: The reason we go out to collect fresh tissue samples
is because the shark skin is still alive,
and thus, theoretically, it should respond to the hormonal treatments we give it.
That's why we're taking these extra steps, so we can make sure the experiment works.
We are bringing the lab into the field.
I've got my sampling probes which I'll attach to the dart gun.
You can see I've got three solutions that give that life-giving fluid
so the tissue stays alive long enough for us to get to the lab.
If we can get live tissue to the lab, apply the hormones,
and witness under the microscope the pigment dispersing and aggregating,
we're getting somewhere. If it dies, it's all wasted.
NARRATOR: A successful experiment
could provide definitive evidence for their color change theory.
But first, they need a sample.
GIBBS: To be in the cage at the shark's level
is probably the best vantage point we're going to get to sample them.
I would lie if I said I wasn't a little bit nervous.
There is an element of danger with dealing with these animals.
RYAN: I'm gonna try to get the bait down past you.
GIBBS: Mm-hmm.
RYAN: And then I'm gonna try to get the shark to follow
and come close to you as possible. And that's when you want to go for it.
-We got this. -We got this.
I think that's-- Oh, bait! Oh!
That's gone, that's gone, that's gone, that's gone, that's gone.
Come on, Gibbsy, the sharks are working, buddy!
GIBBS: The margin of error is quite small.
So I can sample them in the right spot, so that I can get the right tissue
-and also not harm the sharks. -RYAN: Here he comes.
Woo!
-They're fast! -Yeah.
Dang!
MAN: Good eyes.
(camera shutter clicking) RYAN: No, no, no.
He speared it! He speared it!
Nice! It was actually a good placement.
Nice work, Gibbs!
Perfect. Woo! How did that look?
GIBBS: It worked out perfectly.
RYAN: Nice, man. (laughs) Okay, let me process this.
That's the key part we're looking for, the skin.
NARRATOR: With the first sample on deck,
they only have an hour to collect the remaining samples.
We have to make sure that tissue stays alive
-long enough for us to get to the lab. -Look at that.
-Aggressing a lot. -MAN: Here comes the shark again.
And grayer in color.
-Did you see that? -Yeah. Yeah. I did see that.
RYAN: Got it! Got it! Yeah!
NARRATOR: Two down.
RYAN: Perfect shot. My boy has got it. Gibbs is shooting well.
That's where the tissue is thickest.
You're gonna stay far away from any of the vital organs
if you hit just at the base of the dorsal fin like that.
Perfect little skin tag.
-Got it. -MAN: Got it.
RYAN: You know, I know that, I know he's been stressing a lot
about his aim with that, so to actually see it placed
so beautifully just at the base of the dorsal fin...
-It's perfect. -It makes me really happy for him.
Sheesh. Out of the blue, eh?
It is a new shark. Yup.
He was so shy just now, man. Just suddenly...
Torpedo. Shows you what these things got in them when they want to get.
Oh, there he is again. Bring the one that we have.
We have to look on this side of her, this side of her.
See if that-- 'cause he did hit one low.
Problem is if we sampled the same shark twice.
No, no. No, no, no, no, no, no.
Look at that dorsal fin, it's very distinct.
This guy is a player.
-MAN: I think I got it. -It's got that hurt dorsal fin.
Come on, Gibbs, hit the shot, hit the shot.
This could be it, this could be our third successful sample,
as long as Gibbs knows it's one that we can sample.
Here he comes. Here he comes.
-This could be it. -MAN: Turning, turning.
RYAN: This could be it. This could be it. I'm just gonna bring him straight in.
-Oh. -MAN: Oh.
RYAN: Oh, geez!
RYAN: No, come on, Gibbs! You've got this. You got this, buddy.
NARRATOR: Ryan and Gibbs are running out of time.
I think he's a bit shaken from when the shark hit the cage.
Gibbs has had two perfect shots here, but he's not firing.
NARRATOR: Shark's skin begins to die the minute it's sampled.
They need the final skin tag now
if they're going to make it to Cape Town with living tissue.
MAN: Yeah, right in front of him.
-Yeah, he got it. -RYAN: Oh, he got it. Bang on, bang on.
(laughs) Nice.
Yeah, that was pretty good. This should give us some really good data.
Woo! It's on you, man. Well done!
-Thanks. Alright. Let's get out. -RYAN: Get changed, we're pulling anchor.
RYAN: So we've got about four hours, five hours max to get to Cape Town.
So let's move, come on!
NARRATOR: Ryan and Gibbs rush the samples to a lab in Cape Town.
They're seeking the expertise of cellular biologist
and imaging specialist Dr. Dirk Lang.
DR. DIRK LANG: I mean, you guys must have had an incredibly full schedule today.
RYAN: Well, we realized when we got out there, we had about two hours to collect,
and I wanted at least three samples for us.
DR. LANG: Okay.
RYAN: If we can prove that great white shark skin is controlled by hormones,
that's over half of our whole mission answered right then and there.
NARRATOR: While Gibbs prepares hormonal solutions,
Dirk prepares the shark skin samples to ensure they stay alive during testing.
-Hey, guys. -How's it going, Gibbs?
GIBBS: You know, it's my first time going straight from the sea to the lab.
This isn't right for me.
NARRATOR: The shark skin reactions to these hormonal tests
will be documented using a confocal microscope.
RYAN: If we can see microscopically
these pigment cells aggregating and dispersing,
there'll be no doubt that there is color change in these sharks.
NARRATOR: The powerful microscope will allow them
to actually see melanocytes in the skin
and determine whether they react to hormonal stimulus.
GIBBS: So we're gonna see a time lapse, and that might actually help us figure out
how this color change mechanism really works.
NARRATOR: The first test is with the melanocyte-stimulating hormone.
If their theory is correct, this should cause a dispersal of melanocytes
and a darkening of the pigment.
The second hormone is adrenaline,
which they believe would be present during behavior like hunting.
Third is melatonin, a hormone associated with resting.
This could emulate a shark in a relaxed state.
So this is, this is hormones that the sharks
would be producing themselves in different environments.
Now we're flushing the skin with it, trying to replicate the response.
GIBBS: Most people think the most exciting part of my job
is out in the field, but the excitement that I'm getting
from the lab is, is on a different level.
NARRATOR: As the time lapses come in,
it's clear the hormones are affecting the skin samples.
In the sample treated with the melanocyte-stimulating hormone,
the melanocytes have dispersed, making the skin appear darker.
This sample is on a living great white shark, not...
-This morning. -...five hours ago.
That is just so amazing.
NARRATOR: Contrary to their prediction, the shark skin flushed with adrenaline
shows the melanocyte cells contracting and appearing lighter.
This would cause a paling effect. Huh.
NARRATOR: Then there is the melatonin.
GIBBS: We're seeing a mix of light and dark.
RYAN: (laughs) And we're making history.
We're seeing the changes, and you picture this in your head,
that moment when you actually,
wow, these cells are responding to the different hormones.
It, it blows your mind. It's... it's incredible, it's awesome.
-Color change in great white sharks. -GIBBS: This is exciting stuff.
NARRATOR: Though the results are preliminary
and more research is needed to understand the connection
between shark hormones and behavior,
the reaction of these microscopic melanocytes tells a very big story.
RYAN: So what this means is that great whites can control their color
and that the color that they choose to adopt
is controlled by the hormones that they release into their blood system.
I never thought I'd get moved in a scientific laboratory scene.
You know, I'm used to seeing breaching sharks and all that excitement.
But to come here to this sort of cellular level
and see this incredible thing happening
and knowing that this actually means something to science
is, it's special, it is really special.
NARRATOR: It's an incredible discovery
that could totally change what we know about the great white.
GIBBS: I really don't know what to say.
I'm at a loss for words right now, because this is super cool.
And I don't think I'm gonna have another moment like this
in my science career for a long time.
NARRATOR: With photographic and cellular evidence
suggesting this species is capable of subtly changing its color,
this is just the beginning of understanding
the great white as a camo shark.