Echinoderms (starfish, brittle stars, basket stars, crinoids, and sea cucumbers) are marine invertebrates characterized by a water vascular system with tube feet for movement, a decentralized nervous system without a central brain, and remarkable regenerative abilities. Despite lacking brains, they possess sophisticated sensory systems—starfish have eyes at arm tips perceiving light and shadows, while brittle stars use skin-based light detection. These creatures play crucial ecological roles: starfish are apex predators controlling prey populations, sea cucumbers clean ocean sediments and produce calcium carbonate for coral reefs, and sea urchins prevent algae overgrowth. Their unique adaptations, including bioluminescence in deep-sea species and specialized feeding mechanisms like stomach ejection, demonstrate evolutionary solutions to marine survival challenges.
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What The Hell Is Wrong With Starfish?! - Casual Geographic Reaction | Maddiekuma ReactsAdded:
Why are Australians always fighting something? I heard about the Emu War.
Then they have this issue with the toads. But war against sea stars now, too? Like what is happening over there?
Australians, are you okay? You know, Satan was onto something.
Just not sobriety. When he let his sketchbook get uploaded into the ocean from a breast stroking body snatcher to a semi-sentient Sarlacc pit. The greatest trick to go Wait.
I feel like I should have seen these already because I watched so many ocean videos, but I've never seen these. What the hell are those? Why is this thing moving?
>> From an ever pulled was stacking billions of dollars expanding into space before reconciling with the ET-ish already in our face. The sea star and his freak show of a family is a gross out body horror film unfolding at the expense of all who perceive it. The starfish family of a kind of derm has five classes with about 7,600 species across those classes. Each as viscerally disturbing and beautifully unnerving as the next.
Okay, I really hate them. They really do look like aliens. Ooh. You guys know how I don't like centipedes and millipedes cuz they have too many legs. And this is giving the same vibes but like underwater, you know? But starfish are so freaked out for Earth. Their scientific name is Asteroidea. And if a report comes out that aliens have been stowed away in the seas this entire time, the number one suspect would be Lucifer's loofah. The first red flag is starfish ignore the concept of blood.
Instead, they got an open seawater circulation system that actually makes a lot of sense when you realize how they move. It's I hate how those little legs at the bottom move. Starts with the madreporite, a plate that's like the front door of its system that's almost intentionally off center to remind you that symmetry is an earthly concept.
Water moves in through the madreporite through canals until they eventually reach the tube feet, which is how this Lovecraftian fish spinner goes mobile.
Cuz when the valve closes and the eye drop coated ampulla contract, it shoots water into the tube feet and forces them to extend. And when the extended tube foot hits a hard surface, the center retracts forming a seal that only breaks when it's time to move on and stick to something else. Thousands of tube feet doing this dance is how a sea star can move faster than a face hugger ever should. Okay, that is actually very, very interesting how that works, though.
Maybe that wouldn't be as disturbing if sea stars couldn't also see. Starfish have eyes. It's just that if he were real, he'd be standing on them. We've known that starfish have eyes at the end of their arms for 200 years.
>> Oh. At the end of their arms? Damn.
Maybe we as a humanity have known this, but me as Maddie has not known this.
That's crazy. The question is what is sight to an animal without a brain?
Likely something beyond our comprehension. Kind of like the time someone told me blind people don't just see black. They just see >> Nothing.
>> Nothing. Yeah. I went nonverbal for 5 minutes fumbling with the concept. So, the concept of seeing nothing is was explained to me in a way where imagine seeing out of your elbow.
Like there is not you can't, you know?
There's nothing there. So, blind people don't just see black or like I guess some do. Some might have just like really bad vision. Blindness is a spectrum. But technically, when you see nothing, that's how it is. Like try seeing out of your elbow and that's that's it. That's nothing, you know?
It's believed that sea stars don't see the world like you and me. Instead, they see the world in lights, darks, and shadows. One experiment tested this by going to a reef in Japan and pretty much circumcising their eyes with scissors.
After that, they took [clears throat] the eyeless sea stars and those that didn't get theirs lopped off and placed them away from their reef home base. The result was the uncut starfish immediately booked it to the reef while the eyeless ones were left Stevie wondering about the next move. It was also found that even starfish living where sunlight isn't a concept can see.
And out of the 13 species pulled out of the deep sea, all but one of them had eyes including Novodinia antarctica, which has giant pupils and arguably the best vision of this predatory polygon.
And like Mardi Gras, they would flash whenever excited. Except instead of flesh, they'd flash light. In fact, some deep sea star are bioluminescent and many believe that this brainless mess of impulses can communicate through that light. Now, let's talk about that lack of a brain cuz that honestly makes everything Satan Squishmallow does creepier. Instead of a brain, the sea star has a tangled ring of neurons that link signals coming from the arms. But the thing with starfish being brainless is there is no Grand Central Station for signals. Everything's lo- Wait, I just thought of this. Is that why Patrick Star is so stupid?
>> [laughter] >> Is it cuz he just has no brain canonically? Is that is that the reason?
calized and signals can start from anywhere. Once one arm decides to move, in that moment it becomes the dominant arm with all the other ones following its lead. Speaking of arms, they don't always stop at five. The Antarctic sun fish can have up to 50. It's a democratic hive mind that transcends past the need for thought. Sea stars are like aliens that have been hiding in our faces for 500 million years. And the only thing we have in common is as deuterostomes, both starfish and people start life the same way they live most of it. As in [ __ ] And there's no time a starfish identifies more than when it eats cuz the way they feed was straight up ripped out of a scene from Meat Canyon. The best way to describe how horrific nature made this bottom feeder is to describe what it's like to be hunted by one. Imagine minding your business when an almost animatronic manifestation of greed pulls up on you and slaps an arm on your face before then using hundreds of suction cup tube feet to pull your jaws apart and force your mouth open. And not only are starfish way stronger than they should be, your jaw would get tired before he does. And the moment your muscles give and allow half a millimeter of an opening, the starfish would then casually eject its stomach out of its mouth and shove it down your throat just to release enzymes to cook you alive and basically digest you from the inside.
You'd probably scream if you didn't already get your lower jaw dissolved.
The last thing you'd see is the external stomach blanketing you in a corrosive embrace before dragging you back to its gaping maw with the now half digested concept of The sea star is the apex predator of a Stephen King wet dream.
They'll eat mollusks like mussels and clams. And like I said, that involves using brute force to divorce the two halves of the shell until the muscles muscles give out, which might just make it the worst persistence hunter cuz imagine playing tug-of-war with an animal with no working concept of tired and where giving up just a tenth of a millimeter can get your insides turned into soup. And we're talking about a predator that'll spend not just hours but days pulling a clam apart. Also eats sponges like their coral cotton candy and >> Wait. I don't think the implication even needs to be explained. In fact, Patrick would have merked SpongeBob, his family, the kid they raised. I don't know if buddy got a name, but he would have got packed up, too. Their only chance would be Gary using family ties to try and put a hit on him with the giant Pacific triton being one of the few animals able to prey on the crown of thorns starfish.
But starfish will prey on anything that ain't nailed down. And as part-time scavengers, they'll also remove the dead like a garbage disposing job of the hut.
A mother octopus surprised for loving her kids almost to death is a starfish dragging her off to a certain one.
Starfish are also common predators to other starfish as this one is now finding out at the arms of a sun star.
They're different species, so technically not cannibalism. Some owls eat other owls and some cats cook other cats. So, a sea they're the same species.
Which they also do, by the way. Two researchers wanted to find out just what would happen if a bunch of baby He's like they're not cannibals but by the way, except for they are actually. Sea stars were introduced to a possibly predatory crab. They never would cuz the sea star started eating each other before the crab even got involved.
Imagine the Joker pulling up to find the hospital already got leveled by a receptionist. There's a good chance this friendly fire is how a starfish can even the odds when they're just one of millions of eggs that get spawned cuz an animal with no conscious is physically incapable of finding a [ __ ] to give, which is why the Australian government had to go to war against them. It'll never >> Wait. Why are Australians always fighting something? I heard about the Emu War. Then they have this issue with the toads.
I mean, they have a lot of issues in general in Australia.
Not necessarily ones where you have to go to war for.
But war against sea stars now, too? Like what is happening over there?
Australians, are you okay? The crown of thorns starfish is an unhinged pincushion that has been eating the literal life out of reefs. The Great Barrier Reef is one of the most biodiverse spots on the planet. And in the last 30 years, 42% of its coral has disappeared because of the devil's tiara. The response over a quarter of a million thorn demons were perp walked off the senses with them getting one shot of vinegar.
Apparently, vinegar has a 100% kill rate against a starfish and just one injection causes them to fall apart. It means one shot of vinegar can do what used to take multiple injections and can speed run their downfall with trained divers erasing as many as 1,000 living thorns in just one 40-minute dive. Which you could be fooled into feeling bad for if the crown of thorns wasn't also a threat to people. Starfish contain saponins, a detergent-y type of chemical that foams if you shake it in a bucket.
If a starfish's spines enter your body, a mess of saponin does, too. It can cause not only extreme pain, bleeding, and swelling. They can destroy blood cells and cause crippling liver damage.
The chances you get subtracted by a sea star are low, but mama would have raised a liar if I said zero. In 2014, a woman was struck by a crown of thorns and died 13 hours later of anaphylactic shock.
So, my thing is why I don't necessarily feel bad for them. If they don't have a brain, do they have a nervous system where they can feel stuff like pain?
Not sure about that.
And technically, if they don't feel any pain, then killing them probably doesn't hurt them a lot.
And in this case, killing them would be better for the ecosystem. So, I kind of understand why they're doing it. So, that's why I personally don't feel super bad.
death where her throat closed in and suffocated her. Her liver looked like six rounds of alcoholism and a hemorrhage led to blood leaking into her lung air sacs. So, yeah, the crown of thorns star is like an ocean lantern fly. Their potential is worthy of the same treatment. Well, maybe not cuz we microdosed the world without starfish.
It's not good. One of the all-time creepiest diseases has been massacring the starfish population so bad that even other animals are catching strays. Sea star wasting disease starts with a starfish seemingly starving itself and managing to seem even more lethargic than usual. That's when the white lesions start forming all over the starfish followed by the tissues melting around the lesion. At this point, the star's water vascular system fails as the victim deflates. The starfish becomes immobilized as its vessel deteriorates and arms fall off. Except this time, there is no growing back. The end game is a starfish now reduced to a pile of white mushy goo. Wasting disease affects over 20 species of sea star with a body count in the billions. The first recorded plague was on the East Coast in 1972, then again in 1978. In 2013, the blight abolished over 5 billion and in some parts of British Columbia, you couldn't even see the seabed because it was too littered with formerly star-shaped corpses. The disease has ravaged sea stars from Baja California all the way to the Gulf of Alaska and some like the sunflower sea star have had their numbers cut down by 90%. And with all these sea stars missing, the sea urchins they normally eat run wild and absolutely decimate the kelp forest many need to live. For a while, folks suspected this kill switch was flipped by a virus, but after 4 years of research, the truth was revealed. Turns out, it's actually a bacteria, Vibrio pectinocida, that's causing starfish to spontaneously dissolve. I called them zombies, but zombie starfish was already a concept straight out of the pages of Satan's favorite author cuz he made that one, too. Hi guys. If you're enjoying this video, don't forget to like and subscribe. Thank you.
>> And they're not even the zombies that give you the respect of moving at quarter speed cuz brittle stars are the fastest echinoderms and if you have arachnophobia, I'm about to lose your business. Brittle stars move like sea spider imitations that again aren't that fast but are entirely too fast for animals looking like that. Yeah, I'll say I don't love how they're moving.
Again, this is giving me a little bit of the same feeling that centipedes and millipedes gave me where it's just a bit too uncanny. It just makes me feel uncomfortable. Like I accept that they exist. I think it's great when they control their ecosystem, but um you know, just not near me, please.
Their swimming's a lot prettier, though, even if it is the opposite of a fish in how I swim in my dreams. To be fair, dreams are the only place I can swim, but I'm working on it. Like the sea star, they're a mess of tangled nerve cords spilling into the arms. But unlike the sea star, brittle stars don't have eyes. Instead, the sea urchin sees with its skin. This one's was kind of pretty, not going to lie. Extraocular vision means brittle bandits use proteins in the skin called opsins to sense light.
Pretty much the light hits the proteins which sends a response to the brittle star to make it move out of the light.
Meaning its entire body is technically an eye, Ooh. Okay, I would never put it on my hand. Ooh, that's oof, uncomfortable. No, no, no. All right, it's a star that also hates the sun since brittle stars spend most of the day hiding under rocks and crevices. So any light sends them scrambling out of the spotlight like roaches. Some aquariums even trained brittle stars to associate the lights dimming with food and so they would all just crawl out of the woodwork whenever someone would lower the lights. Not bad for an animal that's brainless and has to poop out of its mouth. A mouth that has five jaws, by the way, which is the last thing you'd see if you got merked by one cuz any prey caught in those spines would get crushed to death before being digested. Even something like a squid can get got if it dicks around in the hit range of a bunch of brittles and considering what we know about squid, I don't think you could dream up a worse way to become a was. Brittle stars also catch bodies passively through suspension hunting. But the most cursed version of an already cursed animal is a suborder of brittle stars called Euryalina, aka basket stars. I don't even know what YouTube thought it was doing with this one. Basket stars only have five arms and they branch off into straight nonsense. Arms lined with hooks and spines and when they catch something alive, it'll wrap its arms together and form a basket in like I don't know, 2015 or something with like a cow, but then the cow would like multiply and that grossed me out so much and this is exactly what it reminds me of. I don't know if I can still find that video. If I'll find it, I'll put an image of it. Just that they proceed to branch off into straight nonsense. Arms lined with hooks and spines and when they catch something alive, it'll wrap its arms together and form a basket around its prey, after which the semi-sentient spider web uses tube feet to work the creature entombed in mucus and spines towards its Sarlacc pit of a mouth. It's basically getting eaten alive by a bush. A bush that can move, mind you. The giant basket star will hide in crevices in the day only to climb on top of coral to hunt [music] at night. Also, they get pretty big.
Gorgonocephalus is named after Medusa's head shot and they can have arms as long as 2 and 1/2 ft. Just a nightmare of an animal related to a starfish. But as cursed as a cancerous group can be, the feather star is equally as ethereal.
This biblically accurate angel Yes. Yes, biblically accurate angel hits the nail on the head.
crinoid. There's two classes of crinoids, the marine tickle monster right here and the sea lily. The difference is feather stars seem to have unlocked free will while sea lilies settle down and plant themselves in one spot via a stalk. But let it be known, sea lilies can always drag themselves away when they're motivated enough. And if you're enough to make a sea lily want to walk away, consider that an insult of the highest order. It really is a living fossil with crinoids being around for about 500 million years. So basically the granddaddy of all the nonsense in the ocean. So makes sense that they also have some of the wildest plot armor, too. Crinoids survived several extinctions including the infamous Permian-Triassic which realistically should have been the end of them. It also turns out the same ocean warming that kills coral has zero effect on a feather star. In fact, science says they actually regenerate faster when the heat gets raised. I think if I was diving and that thing swam towards me, I would just lose faith in existence and I would never touch water ever again in my life.
This forgotten feather duster was around before us and best believe they'll be here long after. And yeah, their arms can regenerate and some can have up to 150 on standby, which they need cuz the feather star also has a lot of groupies.
But in this case, the star's the one getting screwed. There are animals whose entire personality is mooching off a feather star and even evolved to have the exact same color. Once one of these ride-alongs find a feather, they feed on it either by chewing on its infinite food glitch in the form of arms or by feeding on its feces. You know what?
They're kind of smart. If the arm grows back, that is literally an infinite food glitch. Hell yeah. It's a moose fresh out the pages of Dr. Seuss with relationships almost as toxic as his marriage. If you know, you know. One fish, two fish, dead fish, new fish.
[music] Except we're not talking about fish and I will not be elaborating further. But the feather star doesn't have it nearly as bad as a sea cucumber.
Hint, they look like what they eat. It's a bottom feeder in every sense of the word. A detritivore living off the dead and decaying. They use tentacles to shovel sediment into their system where they digest anything organic and eject the rest. Which means the sand is actually cleaner coming out than going in. By recycling all the organic nastiness no one else will, sea cucumbers help prevent the same algae blooms that can suffocate fish. Not to mention, their bowel bricks help seagrass grow and even contains calcium carbonate. This looks incredibly fascinating, actually. Which not only builds the skeleton of coral, it even helps reverse ocean acidification. Mind you, a group of sea cucumbers is called a pickle and a reef's worth of pickles can produce up to 70,000 tons of poop a year. And it's estimated the combined cucumbers on Heron Island release five Eiffel Towers worth of product. Woah, woah, woah. They're literally poop machines. No way. And yet with all they give back to the community, some decide that's not enough. With some like the pearl fish using the cucumber as a personal panic room by forcing their way through the squishy's poop chute. I think I've seen that. I think that was mentioned in another video that I watched. The same brown eye they breathe through and it's not just one squatter they have to deal with. One cucumber can have 15 pearl fish packing its prostate.
Bro, that cucumber at that point is just a house. Like it's it's a landlord.
>> [laughter] >> I mean, what's he going to do about it?
He ain't got no hands. What they do have are teeth.
Yeah, that's not its mouth. Another form of self-defense involves violently ejecting the bowels out of the cloaca and respawning the organs they sacrifice in a spectacle called visceral regeneration. But they can be trigger-happy. Some cucumbers butt confetti themselves if you pick them up too fast. Oh, also, sea cucumbers aren't terminally grounded. I'm sorry, this looks so incredibly sus. They can fill themselves up with water and fly through the water column covering almost 60 miles in a day. The heaviest chicken evolved water wings to take flying literally. Probably the closest a cute a sea cucumber's capable of. Or at least it would be if I didn't also just remember sea pigs are a thing. But none of that changes the fact that sea cucumbers get violated so regularly that nature had to spike stripe their sinkhole down south, which the sea urchin somehow decided it wanted for its mouth. The sea urchin's teeth are self-sharpening.
>> Oh my gosh. I'm sorry.
No. Oh, too many moving parts. That that is again a centipede millipede. I can't do it.
>> use it to scrape algae from rocks.
Without them, that algae would smother coral and kill it along with anything that depends on it. Which is surprising cuz most would swear sea urchins only exist to with the natural order. Imagine being so universally hated, you give clout to other animals just by them merking you. Whether you have the pretty privilege of an otter or the personality of a wolf fish, you can make an honest name for yourself off clapping urchins for a living. It seems no one likes a sea urchin. But what if I showed you what's beneath the spines?
Uh Does this do something for you? That is a >> No.
Reminds me of Claydol, the Pokémon, somehow. sea urchin skeleton, also referred to as a test. And let it be known, the test is failed. I still feel nothing. Well, I do feel pity cuz many suffer from underwater alopecia where a parasite can cause their spines to fall out. And someone who's a few follicles away from a first-class flight to Turkey, that's tough. But sea urchins don't get smacked by life and just take it. They have one of the most unhinged forms of self-defense. They'll eject their jaws and launch them like a projectile. Pedicellariae are tiny wrench-like pinchers that scientists thought were parasites cuz they can fully move on their own. Instead, some urchins release a cloud of these mobile jaws that can home in on a predator and release venom if they penetrate past the skin. This spike ball releases hundreds of tiny self-functioning jaws laden with toxins. Which is a lot better than being a cucumber blowing your own back out.
Echinoderms are aliens that missed their return flight and have been figuring out life ever since. And without them, the ocean would be a nastier, poopier, more acidic, lower pH place. So the real horror movie would be the world without them. And on that note, that's going to do it for this video. Drink water, hug your mother, don't touch starfish, they can't consent, tell your father you love him and I'mma see y'all in the next one.
So I will say while I do find a lot of these really gross personally, I'm glad that they exist, you know? That is a fair point to mention. It's good that they're here, but I don't have to love them, you know? I don't have to love how they look. I can just avoid them and appreciate their contribution to society. Let's go. That was very very interesting. I really enjoyed it.
And I will definitely be having nightmares about this later. Yeah, yeah, yeah. Mhm.
>> [music] [music]
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