7 of the Most Uniquely Fierce Sharks

[ ♪ Intro ] Sharks come in a lot of different shapes and
sizes, and not just big, bigger, and “God, help save me!” Worldwide, there are at least 500 different
shark species, and most of them aren’t the bazillion-toothed, seal and surfer-terrorizing nemeses of the deep that Hollywood tells us they are. The great white may have a bite force of more
than one and a half metric tons and a top speed of 40 kilometers per hour, but that stuff is almost boring compared the other species out there. Because slashing, shredding, and dismembering
with mere teeth and/or brute force is not interesting enough for many of nature’s
weirdest sharks. No, these sharks went down evolutionary roads
that produced adaptations like slingshot faces, chainsaw snouts, glow-in-the-dark skin, and
lifespans that rival trees. The Greenland shark looks like a poorly executed
granite sculpture of a much more attractive species, and that’s not even the weirdest
thing about it. In 2016, researchers discovered that Greenland
sharks may be the world’s longest-living
vertebrates. The oldest one they tested
was at least 272 years old, although it could have been as old as 512. Even the low end of that range is way longer
than the previous record-holding vertebrate, the bowhead whale,
which lives for about 200 years. Greenland sharks have such a long lifespan that females probably don’t reach sexual maturity until they’re around 150 years old, which seems like a really long time to wait
for that first date. Now, we don’t know a ton about these sharks. It hasn’t been that long since we discovered
they live so long, and biologists hadn’t studied them much before that. But researchers think the secret to the Greenland
shark’s long life might be the bone-crushingly cold water it lives in, which is usually around 1-10 degrees Celsius. The cold water probably lowers the shark’s
growth rate, along with its metabolic rate, or how quickly it uses up energy. The cold might even affect its genes. Researchers studying nematode worms have found
that cold temperatures can activate anti-aging genes. Sharks are not worms, obviously, but some
scientists think something similar might happen for the cold-loving Greenland shark. The genes might help the shark’s body fold
proteins, for example, keeping it healthy for longer. Misfolded proteins become more common as an
organism ages, and they can cause age-related diseases when they accumulate. The cold could also activate genes that help
the shark fight off infection or get rid of molecules that could damage its DNA. Either way, some of these sharks,
the individual living sharks, have probably been around since before
the American revolution. And that is just weird to think about. The thresher shark might seem sort of average
at first, that is, until you see its tail. The top half of the shark’s tail fin is
as long as the rest of its body, which has inspired all kinds of wild speculation about
these sharks taking down their prey Indiana Jones-style. Ridiculous. Until … scientists found out it was true. In 2010, sharks from one species of thresher
shark, called the pelagic thresher, were observed literally whipping shoals of sardines with
their big long tail fins. The whipping action of the tail fin has been
clocked at 129 kilometers per hour, through water! And is so powerful that it doesn’t just
kill the shark’s prey, it dismembers it. You can see the advantage: Swiping at a bunch
of prey at once means they don’t have to bother chasing around individual fish. And they don’t have to bother with cutting
their food up into bite-sized portions, either, since their whip-tail does that for them. I don’t think Indiana Jones ever tried that
particular strategy, but maybe he should have. The sawshark, meanwhile, uses a very different
weapon for its slicing-and-dicing: its face. It’s like the Leatherface of the deep, with
a rostrum, or snout, that looks kind of like a chainsaw, flat and elongated, and lined
with modified, teeth-like scales. But the saw is more than just a weapon. Sharks have electroreceptors on their heads
called the ampullae of Lorenzini, which they use to sense the electrical fields generated
by prey animals. Sawsharks are bottom dwellers, and their ampullae
of Lorenzini are located on the underside of the rostrum. That, along with the long, mustache-like nasal
barbels located about midway down the rostrum, helps the sawshark locate buried prey. Then, once the shark finds it, it can use
the saw to quickly dispatch it. Goblin sharks are kind of the opposite of
what you’d expect from a deadly predator: They’re sort of flabby and poorly toned, with long snouts and skin that’s a weird pinkish-gray color. But what the goblin shark lacks in good looks
and athletic physique, it makes up for with its own bizarre built-in face weapon: an upper jaw that can be dropped and fired at its prey, and then drawn back again. Kind of like a certain alien that once tried
to eat Sigourney Weaver. The goblin shark’s jaw isn’t directly
fused to its skull, it’s attached more indirectly, with ligaments and extra bits of cartilage. That’s what makes it so freakishly mobile. The shark stretches the ligaments to draw
the jaw back to the rest of its head, then fires it forward by relaxing them. As an added bonus, researchers think the movement
might create suction that draws the shark’s prey towards its mouth. So the goblin shark doesn’t just look like
a movie alien, it also hunts like one. But there’s a good reason for its strange
appearance, too. The shark’s skin is basically see-through
because it lives in the deep ocean, where pigmentation is totally unnecessary. And its flabby body is thought to be an adaptation
to the energy-deficient environment down there. By not having a lot of muscle, the sharks
save the energy they’d otherwise use to maintain it. Goblin sharks are also thought to spend more
time hovering than swimming, probably for similar energy-conserving reasons. Although it’s clearly also hovering because
that’s just super creepy and it’s really good at that. The wobbegong is more of a stealth killer,
with an arsenal of strategies for attracting, apprehending, and ambushing prey. The shark has wiggly lobes on its upper lip,
which to prey, look like yummy things to eat, or maybe a safe place to hide. Except that really, the prey are the yummy
things to eat, and the lobes are the opposite
of a safe place to hide. Scientists think the lobes also help the wobbegong
blend into the ocean floor, where it spends most of its time. Because its prey often comes to it, the wobbegong
doesn’t have to waste a lot of time and energy hunting its food. It just hangs out and waits for its takeout
order to arrive, usually in the form of fish, cephalopods, and other small, doomed creatures. Prey doesn’t even have to come very close,
because the wobbegongs can send their mouths out to meet their prey, independent of the
rest of their bodies. One species, the spotted wobbegong, can extend
its mouth further than the length of its own head. Like the goblin shark, the motion enlarges
the shark’s mouth, which also generates suction that traps prey as it passes by. And if that doesn’t work, they do have another
option: some wobbegongs have been observed sneaking up on their prey. Extra, super creepy. The frilled shark, named for the frills on
its gills, is sort of like an eel, sort of like a snake, and sort of like a thing that tried to eat the Millenium Falcon in the Empire Strikes Back. What it’s not very much like is a shark,
at least not most sharks as we know and recognize them. It really looks much more like an eel … until
you see its bizarre, backward-facing teeth. Scientists think these strange teeth might
be used to lure prey. They’re bright white and stand out against
the dark skin of the shark, so curious fish might be tempted
to come in for a better look. Since the teeth face backward, they hook the
prey and make it very hard to escape. The frilled shark’s mouth is also long and
flexible, like a snake’s. That allows it to open its mouth really wide,
swallowing prey up to half its body length. Frilled sharks live at depths of 120 to 1,200
meters, and they aren’t seen very often, so we don’t know exactly what their feeding
behavior looks like. But scientists think the arrangement of the
shark’s fins, combined with its natural buoyancy, suggests that it might, like, hover
in the water, and then strike at passing prey like a snake. The catshark doesn’t have a whip for a tail,
or a saw for a head, or hooks for teeth. It has a different type of clever adaptation
that helps it survive 500-600 meters below the surface,
where it lives: it glows in the
dark. Catsharks are biofluorescent: They have special
pigment in their skin that absorbs blue light, the only color that penetrates that far into
the ocean, and then re-emits some of the energy as green light. This strategy isn’t as common as bioluminescence, where an organism produces its own light through a chemical reaction. But scientists are starting to realize that
biofluorescence is more widespread among fish
than we thought. It’s just been hard to detect it because the glow is often too dim for us humans to see without special equipment. And in 2016, researchers discovered it in
catsharks. The sharks’ eyes, which are shaped like
a cat’s, are much more sensitive to light. They’re attuned to the blue and green part
of the spectrum, and they have long rod cells that help them see better in low light. So they can probably see the biofluorescence
pretty clearly. We aren’t totally sure what they use it
for, but the researchers think the green glow helps the sharks see each other in the dark. More specifically, it could help them find
mates, an idea that’s backed up by the fact that males and females have different glowing
patterns. In at least one species, the males’ claspers,
which they use to mate, are part of that pattern. There’s still a lot we don’t know about
why some sharks glow, or about most of the unusual qualities on this list. But one thing is for sure: To find the truly
awesome sharks out there, you have to look past those
plain old boring Hollywood sharks to their lesser-known
but weirdly fascinating cousins. Happy swimming, everyone! Thanks for watching this episode of SciShow! If you’re interested in learning more about
some of the strangest animals out there, along with all kinds of other
fascinating science, you can go on over to
youtube.com/scishow to subscribe. [ ♪ Outro ]

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100 Responses

  1. sammy124 says:

    Anyone else also have the physique of a goblin shark ?

  2. aztec999999 says:

    Wow. Thank you

  3. Ken Hoang says:

    I like the San Jose Sharks!

  4. Treyvon Price says:

    ive seen so much animal planet and youtube videos on animals, and i'm still often amazed at some creatures still alive today that ive never seen. The ocean is amazing.

  5. Jack Hughes says:

    A-ha-are you saying… that goblin sharks’ mouths… are attached by…


  6. A Trex says:

    should have added the coockiecutter imo

  7. Isaiah Stone says:

    What the hell is a aluminum falcon?

  8. crazycatlady39 says:

    Bullsharks have to be the most dangerous to humans, they can go into freshwater. It's not unusual for them to go up a river. As matter of fact there's a golf course in like Australia that has Bullsharks living in the water hazard. They swam up during massive flooding and got stuck when the water retreated. Had a section on it on The Weather Channel on one of their educational programs. The were talking about flooding and problems it causes. Sharks in your pond would definitely be a problem!

  9. That One Guy With The Face says:

    Its pronounced "amp-u-lie" just fyi.

  10. Tart Nouveau says:


  11. bruh says:

    I don't care how horrifying the saw shark is supposed to be. They're ADORABLE

  12. JokerHellFire Z says:

    I got a quest for you.



    Then let's go kill some Goblins then.

  13. Drywash Only says:

    Gruber D. F. .et al. …huh

  14. VGMajor says:

    I couldn't not laugh at the name Wobbegongs

  15. dolomedes tenebrosus says:

    So awesome. I love these animal showcase episodes. I always go look up the ones that are strange and new to me after the video. Thanks for giving me fun stuff to look up, scishow!

  16. h2o david100000000 says:

    Ur mom!!!

  17. Gökhan Sözeri says:

    You are famous. Be more careful with your wardrobe, sir.

  18. Shazzkid says:

    Sharks with lazers

  19. Angelica Cushing says:

    Instead of chewing my burrito Im going to whip it into a smoothie like a thresher shark.

  20. dopeymetalbud says:

    Can we spend less time looking at your dumb face and more time seeing the actual things you're talking about?

  21. StikyyFeet says:

    I love how Hank is trying to look formal yet he is wearing a pizza shirt

  22. Irma Vep says:


  23. Kieran E says:

    How was Brit not in this video?

  24. Latina Broadway Lover says:

    I'm quite a fan of the ghost shark

  25. Jesse Woodworth says:

    Yes, but what about Baby Shark?

  26. Shabam4895 says:

    Your English captions suck. Most of the time there isn't any caption at all

  27. Mark Kmiecik says:

    Take-out orders don't arrive — delivery orders. You have to go get take-out orders. Ooooops!

  28. Hama Scarlocke says:

    Honestly I think they’re all pretty cute in their own ways, like the goblin is cute to me in a kind of sad ‘please love me’ sort of way. And I just wanna give all these cuties a kiss on their sweet little heads, especially the Greenland and the cat shark. Weird of me, perhaps, but I tend to find the weirder looking creatures out there to be just as cute as puppies and kittens. Probably why I baby talk to my tarantula like he’s some eight-legged cat

  29. Tillie Stanton says:

    Cookie cutter sharks anyone???

  30. Rob Rosen says:

    Sharks have a Chuck Norris Week.

  31. Albrecht von Stollen says:

    Are they tsundere sharks?

  32. Honore Chaisson says:


    Me: *adds Wobbegong to my vocabulary*

  33. Beau Daniel says:

    I love you Hank!

  34. SoloBro says:

    I’ve been watching your videos since you first started. It’s crazy to think about how much everything’s changed. Yet your videos bring back that worry free feel.

  35. Marc A. says:

    This is why sharks are my favorite animal.

  36. Spotted Hyena says:

    Why Is Left Shark Not On The List

  37. Kenyon Thomas says:

    You know how fish that dwell deep in twilight zone have super light sensitive eyes well when humans go down there and shine lights do we blind them

  38. voltix54 says:

    no cookie cutter sharks?

  39. Purple Gladiator says:

    wobbegong. my life is complete.

  40. LORDBADASS says:

    I didn't think Sawsharks actually sawed fish.

  41. Mr. N says:

    Really; No Cookiecutter?

  42. john peters says:

    Hank Green is my favorite SciShow host

  43. Paul Chung says:

    This was made on my birthday haha

  44. edc2879 says:

    Frilled shark 3 year long pregnancy

  45. Daniel Lord says:

    *cough* NINJA LANTERN SHARK *cough*

  46. Victor Roman Flores says:

    Why there isn't Reggae Shark in this list?

  47. DemiDem707 says:

    Zac Efrons Ted bundy -thresher shark

  48. the 'other' party says:

    OMG. When did you get so funny.

  49. B0rder55 says:

    He's wearing a pizza shirt. Must be PiZzAgAtE

  50. One Random Potato says:

    Mcdonalds lady: What size fry would you like?


    God help save me

  51. Sparrows says:

    5:54 I have to maturity- the wobblydong

  52. Sansot Andréa says:

    wobbegongs also have a tail that mimmicks the movement of fish, it attracts other fish thinking this is a safe spot and then… well it was not a safe spot!

  53. Jade Neal says:

    Sooooo basically light up genitals? Okay then.

  54. Mr.Pikachu says:

    If an animal can mimic the chain catshark’s glow, would it be considered catfishing

  55. Maya Smith says:

    I feel bad for all the sharks that live in captivity.??

  56. Werty Werty says:

    Well done Sci Show team, that video was especially interesting and funny!

  57. geekygoldfish girl says:

    I love your show!

  58. Raistlarn says:

    No cookie cutter sharks?

  59. Rosance L says:

    Angler fish:I'm the most terrifying animal in the entire world!!!!!!!!!
    Goblin shark:hold my lantern fish burger.

  60. Danny Landrum says:

    Greenland Sharks: Don't have sex for the first 150 years.
    Any dad of a girl: We that's still not long enough.

  61. Tim T says:

    Pardon for being a killjoy but — the ferocity aspect of Greenland Sharks wasn't pointed out. How are they "uniquely fierce" as per video title?

  62. Amberlance says:

    what about the cookie cutter shark?

  63. Voltaic Fire says:

    Between 272 & 512 years old eh? I want my age to be that nebulous so I'd appear 17 in my 80s lol.

  64. Voltaic Fire says:

    Keep chilly and live much, much longer? If it weren't for fast food the Scottish would be immortal.

  65. Decree Op says:

    Hank! You make the best videos!!

  66. jonathan balagtas says:

    I love how he explained everything. ?
    I laughed so hard. ?

  67. Varsocona says:

    "He who wanders through the darkness with a stick is blind. But he who sticks out in darkness is… Fluorescent!"

  68. Kejsik Zbruśniaczysko says:

    Thresher sharks are my favorite

  69. lk8856 says:

    It’s a woe be gone.

  70. Toothy says:

    hey, editorial note! i dont know if you guys will even see this but, goblin sharks are not actually flabby in the water! they only look so gross and weird when theyve been removed from the deep waters they normally live in, where pressure is much greater and intense compared to the light fluffy atmosphere we have up here. they get crushed under their own density (an adaptation needed for living so deep) and get all flabby.

    you can see how they REALLY look in that little diagram you showed of the stills of the shark flinging its jaws out, when its mouth is retracted! at 4:57

    this same stigma is placed around the blobfish, another deep dwelling marine animal who, when removed from the water, looks like a blob. but in the water, it looks pretty normal!

  71. XxBurritoBearXx says:

    Alabama sharks

  72. mike misurelli says:

    This guys voice is terrible, i think my ears are starting to bleed

  73. Sammy Barnes says:

    You totally ignored the cookie cutter shark which… You probably know more of the creepy details of this miniature nightmare than I do.

  74. Henrik bjørnstad says:

    If i was a deep sea shark i would be to scared of the deep and other sharks to live a normal shark life. Thank god im human

  75. John says:

    What’s the difference between bio fluorescent and bioluminescent?

  76. Yonas K says:

    1:00 damm dude what did greenland sharks ever do to you???

  77. David Meyer says:

    Most kids love dinosaurs when they're little. I was fascinated by sharks. And the thresher shark was always my favorite.

  78. miloš benčič says:


  79. Bubblegum Bird says:

    How come there not extinct when hundreds of million are killed for greasy soup

  80. Bubblegum Bird says:

    No stethacanthus?☹

  81. Snorty Mcsnifface says:

    Where is that blokes chin

  82. Kristen Snead says:

    If I may talk about extinct sharks, may I introduce you to the Helicoprion…

  83. Rinaz Najim says:

    I cant take my eyes off from that pizza

  84. Frida says:

    The sawshark is not a shark its a ray

  85. Max S says:

    Ya know, not the biggest fan of the ocean in general so I think imma just chill here on land, thank you very much

  86. TenorCantusFirmus says:

    #1: Each individual shark can lurk waiting for eating you for 500 years.
    #2: If you stay away from their jaws, they still can torn you into pieces with their tail…
    #3: …or nose…
    #4: …but they still can make their jaws being thrown towards you!
    #5: And if you wish a typical reef sandbed is safe because there are no sharks in sight, one might be ambushing you under the seabottom.

  87. Adrian C says:

    I think Greenland sharks know Scrooge mcduck's secret to eternal life

  88. Steve Huffman says:

    Fierce and Deadly sharks and you don't even mention the Bull Shark, the worst of the lot.
    They not only can, but do thrive in freshwater.

  89. Hydroponic City says:

    Ok pizza Jersey and a blazer? Dude where you got that fashion statement gargamel? ???

  90. Ирина Климова says:

    Ur so funny

  91. StarlightEater says:

    Psh no megamouth?

  92. tyler borders says:

    A goblin shark is a demagorgan that stayed in the water too long

  93. NOVA 6 says:

    What about the cookie cutter shark

  94. Connor Knight says:

    To bad us humans can’t live longer in the cold anyone love the cold ?

  95. Seiyuōkami Himura says:

    Wobbegongs are my favorite. Especially ornate wobbegongs.

  96. TheMasterSpoon says:

    Finally a video of my favorite 5 sharks. I love sharks so much and Hollywood really needs to back off the great white shark

  97. IronGiantCraft 1 says:

    Forgot the basking shark guys.

  98. Gus Griswald says:

    How do I get Hanks job? I wanna dress up in a suit jacket and talk about sharks

  99. L Johnston says:

    Indiana Jones
    Star Wars

    Harrison Ford is a shark

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