Dismiss this pinned window
top 200 commentsshow all 392

[–]__Prime__ 139 points140 points  (3 children)

Crazy that these things are about 200 million years older than trees.

[–]occams_nightmare 87 points88 points  (0 children)

And they still don't look a day over 100 million

[–]theonetheonlytc 563 points564 points  (50 children)

These guys are so cool. They have also remained basically unchanged for a few hundred million years. Their blood is blue and is important for use in the pharmaceutical industry. Super cool creatures and I love encountering them while free diving.

[–]robo-dragon 364 points365 points  (40 children)

I love how “ancient” creatures just look ancient. Like you don’t even have to know their ancestors walked with dinosaurs, their appearance is enough to tell their story.

[–]Harvestman-man 47 points48 points  (29 children)

What constitutes “looking ancient”?

Would you say these guys look 400+ million years old?

[–]dompam 67 points68 points  (2 children)

They look terrifying. Thats all i need to say.

[–]Thebesj 33 points34 points  (18 children)

Hm. No. Not all of them do. Sharks neither. BUT the horshoecrab, with it’s armor definetly has an ancient look to it

[–]Euphemisticles 16 points17 points  (14 children)

Despite outside appearances sharks have probably changed a lot in the hundreds of millions of years they have been around

[–]DannyMThompson 47 points48 points  (13 children)

Sharks are older than trees

Ty for the downvote, go Google it.

[–]mr_evil66983 12 points13 points  (1 child)

Ur right cuz sharks were a thing before we had any dry land on this planet

[–]stone111111 3 points4 points  (9 children)

Sharks are old and there are a few niches filled by sharks that have had similar looking sharks in them for a very long time. Other sharks have evolved massively to fill different niches. Both can be true

[–]DannyMThompson 8 points9 points  (8 children)

I was just adding an interesting fact not starting a debate. What is with Reddit?

[–]nuke-proof 5 points6 points  (1 child)

Egotistical people who can't help but try and seem intellectually superior to one another

[–]Evilmaze 5 points6 points  (0 children)

The one-up syndrome where people can't just go like "oh that's interesting, I never knew that information". Instead they just try to argue and piss you off. Commenting lately guarantees some asshole saying otherwise regardless of how factual your statement is.

[–]stone111111 3 points4 points  (5 children)

Idk what got your jimmies rustled, I just wanted to talk about sharks too.

[–]DannyMThompson 1 point2 points  (4 children)

The fact my karma was in the minus for just adding a cool fact about sharks lol

[–]Jbigga500 1 point2 points  (0 children)

“Google it; it’s worth the google”

[–]DudeJustShutUpPlease 3 points4 points  (0 children)

Add a long enough beard to that image and it's a strong maybe.

[–]timboslice23 2 points3 points  (0 children)

What’s crazy is they predate the dinosaurs by over 300 million years

[–]Detrimentos_ 1 point2 points  (0 children)

ancestors walked with dinosaurs

These crabs were there way before dinosaurs too.

[–]nahomboy 3 points4 points  (0 children)

I heard they are bled though. Like in a cruel way.

[–]Dawanna 7 points8 points  (0 children)

Blue blood you say. Sounds like and angel to me. Time for Shinji to get his ass in that EVA.

[–]Emotional_Liberal 777 points778 points  (87 children)

Fun fact: horseshoe crab blood is harvested for the medical industry

[–]weaselgirl13 471 points472 points  (48 children)

Funner fact it’s worth 15k a quart :)

[–]Emotional_Liberal 522 points523 points  (42 children)

Sad fact: An estimated 23K+ die in the process

[–]IvyMoonfyre 707 points708 points  (21 children)

A better fact: an alternative had been found, meaning the bleeding of horseshoe crabs is coming to an end.

[–]PeteDaBum 383 points384 points  (10 children)

What a roller coaster this thread has been!

[–]butterymales420 145 points146 points  (9 children)

Their blood is blue too!

[–]namedonelettere 101 points102 points  (5 children)

Informative fact: Their blood contains potassium benzoate


Nutritional Fact: That’s bad

[–]heysame 25 points26 points  (0 children)

I’ll take that frogurt

[–]Tarukun564 11 points12 points  (3 children)

But it comes with free frogurt!

[–]Caridin 5 points6 points  (2 children)

Thats good!

[–]shadowinc 6 points7 points  (1 child)

The frogurt is also cursed.

[–]Banggabor 6 points7 points  (0 children)

Hey! My piss is like that! Cool!

[–]FallenSegull 1 point2 points  (0 children)

Unrelated but so are my balls

[–]M4Dsc13ntist 12 points13 points  (4 children)

I'd be interested in knowing what their blood was used for, and what alternative were discovered.. any chance I'll learn that here?

[–]dangerouspowerlab 39 points40 points  (0 children)

An extract of their blood known as Limulus amebocyte lysate (LAL) produces a chemical reaction in the presence of endotoxin producing bacteria.

This is used as the basis for endotoxin aka LAL tests used to ensure drugs remain free of contamination throughout the manufacturing process.

[–]WarKiel 12 points13 points  (1 child)

I believe it is used to test certain types of medical equipment and drugs for contamination.

[–]feskslo 9 points10 points  (0 children)

The other responses have you covered already, but if you want to know more Radiolab did a great episode on this a few years back. Highly recommend.

Here's the link https://www.wnycstudios.org/podcasts/radiolab/articles/baby-blue-blood-drive

[–]Jksukino 1 point2 points  (0 children)

Wait, I need this to be true. Please give me the source

[–]dieselwurst 9 points10 points  (15 children)

Horseshoe crabs do not die during harvesting. What's your source?

Edit: i see you're referring to the consumption of horseshoe crabs thereafter. Not a fair comparison as they don't die "in the process" of blood harvesting, but I'm also not mad at people eating horseshoe crabs pre or post blood harvestment.

[–]Emotional_Liberal 48 points49 points  (3 children)

A lot do die during bleeding, it’s estimated 23k-140k per year. I don’t disagree with the eating part tho.


[–]Cyniikal 22 points23 points  (1 child)

frontier Sin always sounds to me like a porn studio that exclusively does old west cosplay porn

[–]the123king-reddit 2 points3 points  (0 children)

Dons Arthur Morgan costume

"there there girl..."

"Good girl..."

[–]Goodparley_1492 4 points5 points  (0 children)

I used to work as a fisheries observer for NOAA on boats that harvested horseshoe crabs for medical purposes. Some commercial fishing trawlers get contracts with the med companies to harvest the crabs and are given them back to dump back in the ocean on their return trips. Medical wants the big females that don't have any damage from being harvested, after they reach that quota some more were kept to sell for bait in whelk pots. Some other boats without medical contracts would harvest them for sale as bait too but I've never heard of a food market for them in the US.

[–]Luxpreliator 10 points11 points  (2 children)

They die due to the blood harvesting if your position is a technicality that they don't die specifically in the harvesting building.

they pierce the tissue around the animals’ hearts and drain up to 30 percent of the animals’ blood

Between 10 and 30 percent of the bled animals, according to varying estimates, actually die.

In short: Bleeding a female horseshoe crab may make it less likely to mate, even if it doesn’t kill it. (Only 18 percent of the crabs the authors tracked died.)


[–]joemckie 11 points12 points  (1 child)

Man imagine being one of those crabs, taken out of your natural habitat and put in a lab to be subsequently stabbed with needles an drained of a third of your blood. It’s like their version of an alien abduction.

[–]svartkonst 2 points3 points  (0 children)

alien abduction stories are scary because we fear being treated the same way we treat animals

[–]Scrapper-Mom 4 points5 points  (3 children)

Also funner and interesting fact, their blood is blue.

[–]TomPalmer1979 1 point2 points  (0 children)

Stupid rich hoity-toity crabs and their blue blood...

[–]Birbicorn 10 points11 points  (23 children)

What is it used for?

[–]unwantedposterboy 55 points56 points  (8 children)

[–]DoubleDot7 46 points47 points  (6 children)

Summary: it's used to detect bacterial contamination.

It's worth clicking the link just to see what people mean by, "Its blood is blue!"

[–]hypermarv123 5 points6 points  (3 children)

Where my LAL people at!?

[–]panaja17 3 points4 points  (0 children)

I used to do LAL testing. It’s more ethical and precise than the rabbit testing they did before they discovered LAL testing and methods now help it go a long way. Like $10,000 worth of it can be used to test over 1,000 devices. We always tried to maximize LAL because that stuff is expensive.

[–]RohelTheConqueror 4 points5 points  (0 children)

Not just blue, baby blue!

[–]AwwSchnapp 2 points3 points  (0 children)

The real MVP - but also, what a sad photo :(

[–]Guccimayne 3 points4 points  (0 children)

We use it to detect endotoxins from bacteria. Endotoxin can cause an unintended inflammatory immune response in the body, so it needs to be removed from the therapeutic you’re investigating.

[–]DarkReaver1337 1 point2 points  (0 children)

It’s used for Sterilization purposes. The blood sort of clots when it comes in contact with bacteria and other foreign bodies. So when you need to test if medical equipment is Sterile it does the trick.

[–]Mungus_Prime 1 point2 points  (0 children)

You know how human blood is bliss until it comes in contact with oxygen and then it turns red? Well this crab's blood doesn't do that so it can be safely used as human blood replacement.

[–]Emotional_Liberal -5 points-4 points  (8 children)

It’s used primarily in the medical industry. In Asia after being bled they’re sold in secondary markets for consumption. https://www.theatlantic.com/science/archive/2018/05/blood-in-the-water/559229/

[–]Willthesciguy 30 points31 points  (5 children)

wow it’s use in the medical industry is that it’s used in the medical industry??? You don’t fuckin say.

[–]xkcd_puppy 23 points24 points  (2 children)

It's used to do medical things like make medicine for medicinal purposes for people who need medical medicine.

[–]zoloftisdeath 2 points3 points  (0 children)

Medical medicine

This sent me for a giggle

[–]redditpulledmebackin 4 points5 points  (0 children)

Damn it man we don’t have time for your medical jargon! In English!

[–]Birbicorn 3 points4 points  (1 child)

That’s fascinating and very sad at the same time

[–]Emotional_Liberal 9 points10 points  (0 children)

Chin up. There’s hope in an artificial substitute.

[–]solar-cabin 4 points5 points  (0 children)

Certain laboratory tests developed from horseshoe crab blood are used to detect bacterial contamination in everything from heart stents, saline drips, and flu shots, to surgical implants such as pacemakers and prosthetic devices.

Once the LAL has been withdrawn, the crabs are returned to the wild. The horseshoe crabs typically spend one to three days in the lab while the LAL is extracted. They can survive out of water for up to four days, as long as their gills stay moist.

The crabs are then returned to the fishermen who originally caught them, to be gently placed back into the sea. “We treat these crabs like babies,” Yahoo News reported one fisherman saying. “Blue bloods save lives,” said another fisherman.


[–]nodustspeck 55 points56 points  (3 children)

They can get pretty big - 18 inches or so. As they grow, they molt, shedding their entire exoskeleton. I have a small one, amazingly intact, that I found on an east coast beach last year.

[–]thedude1179 12 points13 points  (0 children)

Thanks I was wondering about how they grow with their shells.

[–]Wave_Table 6 points7 points  (1 child)

Fun fact: If you find a horseshoe crab malt, you can break off the tail to use as a shank!

[–]Threethirtysix[🍰] 252 points253 points  (5 children)

If you take care of it long enough, it'll grow into a Kabutops.

[–]in_direct 41 points42 points  (1 child)


[–]hujijiwatchi 17 points18 points  (0 children)

This isn't the time to use that!

[–]grateful-smile 9 points10 points  (1 child)

More like Golisopod

[–]carlsaganistic 112 points113 points  (9 children)

Nice doggy…

[–]KGdotdotdot 21 points22 points  (2 children)

Everything's comin' up u/carlsaganistic!

[–]carlsaganistic 9 points10 points  (1 child)

The house always wins!

[–]disabled_crab 6 points7 points  (0 children)

At least I'm doing better than Dad.

[–]Detrimentos_ 5 points6 points  (0 children)


[–]slopokerod 9 points10 points  (3 children)

Did a search thinking that nobody would ever make this reference. That's it, I'm done, I can no longer have original thought.

[–]Technol0jesus 5 points6 points  (0 children)

I feel good to be a part of this with you

[–]ceelose 4 points5 points  (0 children)

Mate, Simpsons references are physically hard wired into the white matter of most of our brains. Of course it wasn't original. Don't feel bad.

[–]RacingNeilo 2 points3 points  (0 children)

I'm just happy to finally know what Milhouse was pettin

[–]heavyfriends 3 points4 points  (0 children)

Haha! You got the dud!

[–]Eevo_The_Eevee 18 points19 points  (4 children)

Lil’ baby Mirelurks

[–]fluffy_AI 6 points7 points  (2 children)

Who else loves mirelurks? (I love them, because I love crabs and crustaceans and they are basically that)

[–]waterbasednoodle 1 point2 points  (1 child)

I like the sounds they make!!

[–]fluffy_AI 1 point2 points  (0 children)

Eheh they are so cute

[–]zailynne 16 points17 points  (0 children)

I didn’t realize the little ones were so cute but now I would die for them??

[–]AnUnquietHour 69 points70 points  (6 children)

They're so cute!!

[–]HolyNarwhal 62 points63 points  (2 children)

Yea when they’re right side up. Little nightmares underneath that shell.

[–]Limp_Resist_2954 16 points17 points  (0 children)

I genuinely used to have nightmares about the underside of the shell - absolutely horrible 😭

[–]RedPanda888 6 points7 points  (0 children)

The large ones are terrifying. My girlfriends mum came back from a market in Thailand with one once and the barb/tail thing was sticking out the bag and I was like what the fuck is that.

Turns out they eat their eggs or put them in food dishes. They have no meat, just scoop out the eggs. Looks terrifying, tastes average.

For anyone who thinks they’re cute, wait until you see the underside and their legs. It’s like the most terrifying spider/scorpion/crab combination you can dream up.

[–]istolee 4 points5 points  (1 child)

Right I want to hold or see one so cool

[–]Thaksin_Shinawatra 1 point2 points  (0 children)

They really are cool and harmless. I live along the East Coast of the US and they are very common to see at the beach.

[–]MatsutakeFairy 12 points13 points  (4 children)

Omg that’s adorable. I’ve never seen that type of animal before and I’m absolutely in love with it!!!!

[–]piiing 9 points10 points  (2 children)

don’t google pics of the underneath of it then. let them stay cute in your head.

[–]Wave_Table 5 points6 points  (1 child)

I never got this. It’s just legs. I feel like it’s exactly what you would expect if you haven’t seen it.

[–]key_xchange 37 points38 points  (0 children)

Their shells are white and soft; not yet hardened and darkened by the evils of the world.

[–]short-for-jordaniel 6 points7 points  (0 children)

Here we see the ancestor of the modern roomba

[–]robo-dragon 16 points17 points  (1 child)

Horseshoe crabs, no matter the size, are oddly adorable. Not sure what it is about them that makes them so endearing, but I absolutely love them!

[–]PeachyLittleLemon 14 points15 points  (3 children)

Random shower thought I recently had. “wonder if the blue milk from tatooine is actually horseshoe crab blood?”

[–]DeffoDan 4 points5 points  (1 child)

I always wanted to pet one, they’re like little plates that walk around ;-;

[–]Jealous_Tangerine_93 4 points5 points  (0 children)

They look like amphibian tanks

[–]Trailwatch427 3 points4 points  (0 children)

They breed in the estuary near my home. To see them gathered or washed up on a sandy river bank, suddenly it's like the Devonian era.

[–]Owls_yawn 13 points14 points  (2 children)

Is there a horseshoe crab sub?

[–]GisterMizard 11 points12 points  (3 children)

Say what you want about the Cambrian explosion, but it sure did manage to produce some cute little fuckers.

[–]Harvestman-man 5 points6 points  (1 child)

Horseshoe crabs only date to the late Ordovician; they’re not quite that old.

[–]Mystery--Man 10 points11 points  (1 child)

Cute until you flip the things over then it's just AH!

[–]TraceyNunyabiz 5 points6 points  (0 children)

So cute!!

[–]nemolizard 5 points6 points  (0 children)

Absolutely adorable.

[–]peteoneillbassnyc 3 points4 points  (0 children)

Batteries not included

[–]supermav27 3 points4 points  (0 children)

Let this be a lesson that just because something isn’t furry or has big eyes, doesn’t mean that they’re not an innocent little creature who appreciates love and kindness.

[–]socratessue 4 points5 points  (0 children)

They look like little wind-up toys

[–]FerroLux_ 4 points5 points  (0 children)

Mfs walked the earth when dinosaurs weren’t even a thing and look a them go. Perfect design

[–]Kryllllllyx 2 points3 points  (0 children)

Long live these little guys (literally)

[–]PM_A_JOB_GIRL 2 points3 points  (2 children)

Beginning looks like a blue shell from mario kart

[–]protogenfan 1 point2 points  (0 children)

That shits scary

[–]Jessicafletcher2 1 point2 points  (0 children)

Reminded me of the mini bowser clan.

[–]Smarty93 2 points3 points  (1 child)

I have studied the American horseshoe crab for over a decade! AMA!

[–]doomer- 1 point2 points  (0 children)

Are they intelligent?

[–]Drix1942 2 points3 points  (0 children)

horseshoe crab

[–]oo-mox83 2 points3 points  (0 children)

They're so precious!!

[–]maximumplague 2 points3 points  (0 children)

I never even considered that they would bend like that.

[–]warkifiedchocobo 4 points5 points  (0 children)

Ahhhh my heart is melting! They're so cute! I love horseshoe crabs! 😍😍😍

[–]mccmrg 1 point2 points  (0 children)

I want to touch them

[–]RedShiftyz 1 point2 points  (0 children)

I don’t wanna step on them, for my sake not theirs. Maybe theirs too

[–]set-271 1 point2 points  (0 children)

So cute!!!

[–]mahbobol_hasan 1 point2 points  (0 children)

I never watched them before. Really they are pretty cute.

[–]Novel_Bonus_2497 1 point2 points  (0 children)

omg I didn't know they were so smol

[–]cornonthekopp 1 point2 points  (0 children)

Digging in the sand for baby horseshoe crabs was a lot of fun at the beach when I was a kid

[–]Moist_Band-Aid 1 point2 points  (0 children)

Nature’s roombas

[–]Je_GuLling 1 point2 points  (0 children)

Ocean roomba

[–]captain_zavec 1 point2 points  (0 children)

I don't know where this is but I want to go there.

[–]Diora_Diovana 1 point2 points  (0 children)

sea roomba

[–]queenofomashu 1 point2 points  (0 children)

Sand roomba :3

[–]Eviyel 1 point2 points  (0 children)

Lol it looks like their animations won’t load when they start walking so they’re just a frozen model sliding around

[–]BaconSyrop 1 point2 points  (0 children)

Good doggy

[–]EarAtAttention 1 point2 points  (2 children)

But can they swim upside down?

[–]educatedvegetable 1 point2 points  (0 children)

But do they know they are precious sweet baby angels?

[–]PragmaticBadGuy 1 point2 points  (0 children)

I still have a hard time believing those are real or at least not extinct. I know they are alive and swimming around but still.

[–]SweetDiancie 1 point2 points  (0 children)

Oh it's similar to gloisopod

[–]Quasar_Cross 1 point2 points  (0 children)

Straight up pokemon. Nature really is lit

[–]DeafeningClarion 1 point2 points  (4 children)

Can I keep one as a pet? Like honest question i always loved them. Like in an aquarium?

[–]HotDamImHere 1 point2 points  (0 children)

Nah bro thats a pokemon

[–]Rdog9220 1 point2 points  (0 children)

Whats with reddits obsession with horseshoe crabs lately?

[–]sodamnsleepy 1 point2 points  (5 children)

I bet it tickles to have them on your hand.

Where do they live?

[–]Aethermancer 2 points3 points  (1 child)

When they are laying eggs I would always find them on Delaware's beaches.

[–]strange_pterodactyl 1 point2 points  (1 child)

Shallow costal waters on the eastern US (and some other places)

[–]the-cunning-ham 1 point2 points  (0 children)

Meh it's not that sma-

[–]Patchogs 1 point2 points  (0 children)

Nature's Lego

[–]paduwan 1 point2 points  (0 children)

they can make you really rich

[–]whataball 1 point2 points  (0 children)

That's a living fossil right there.

[–]ColonelSpudz 1 point2 points  (0 children)

Real blue bloods

[–]oasisreverie 1 point2 points  (0 children)

They remind me of manta rays.

[–]Hanakiva 1 point2 points  (0 children)

Little living computer bears

[–]axie36 1 point2 points  (0 children)

So cute! Are they harmless?

[–]le_shithead 1 point2 points  (0 children)

Do they pinch?

[–]mr_evil66983 1 point2 points  (0 children)

My favorite crab speacy

[–]atabey_ 1 point2 points  (0 children)

It's all cute and dandy until it's mating season for them. They have a yuge orgy and there are literally hundreds of them on the beach laying eggs from May - early July, it's neat but also pretty spooky.

[–]grandpagrandpaa 1 point2 points  (0 children)

Can these guys give a good bite like a normal crab? I need to hold one of these.

[–]manmega2 1 point2 points  (1 child)

Arent those poison type animals?

[–]nullagravida 1 point2 points  (0 children)

quite the opposite, their blood used to be made into a very important substance required for manufacturing antibiotics

[–]zizovo 1 point2 points  (7 children)

Can't imagine how that would feel on your hands

[–]nullagravida 2 points3 points  (3 children)

probably like a bunch of gerbils under a bowl

[–]zizovo 2 points3 points  (2 children)

Makes sense

[–]nullagravida 1 point2 points  (1 child)

thanks for not wondering if i used to put gerbils under a bowl lol. it was a parkay tub ok,?!? kids do kooky stuff

[–]zizovo 1 point2 points  (0 children)

I just will continue not asking

[–]Character-Ad1290 1 point2 points  (0 children)

Cute little baby Kabuto

[–]millennium-popsicle 1 point2 points  (0 children)

Baby kabuto(s)

[–]MamaSmAsh5 1 point2 points  (0 children)

Growing up on the east coast in Maryland, we'd go to the beach during mating season for these guys and they literally line the shore. You have to watch where you walk and stuff. Cool and underrated creatures!

[–]usernmtkn 1 point2 points  (0 children)

Horseshoe crabs are the best.

[–]song4this 2 points3 points  (0 children)

I had some of these in an aquarium years ago before they got vampired / protected. Goofy lil happy campers! Corners are rare in nature some sometimes they'd just butthead into a corner and the lil feets would just flail... They'd kinda go into reverse / flip around when it's feeding time...

[–]TsunamiGamer140 3 points4 points  (2 children)

The underside of those look less.....appealing than their topside.

[–]fluffy_AI 1 point2 points  (1 child)

I don't get it, their underside doesn't look scary at all, (or I just love crustaceans too much)

[–]Wave_Table 2 points3 points  (0 children)

Yeah, this thread is the first time I’m hearing this. It’s just… legs.

[–]-Masderus- 1 point2 points  (0 children)

Fucking blue turtle shells...

Sorry just having Mario Kart flashbacks.

[–]BerzerkerGamer 1 point2 points  (0 children)

Oh yeah they are all cute until you flip them over, scream, and yeet them into the ocean.

[–]TheBulletBot 1 point2 points  (2 children)

Wimpod, the Turn Tail Pokémon. A Bug and Water
type. From beaches to seabeds, Wimpod live in all kinds of places. They
eat anything, even if it's rotten. Nature's vacuum cleaners!

[–]The_yeetyboi289 1 point2 points  (1 child)

I would hate to step on them

[–]PlasticSugar_God 2 points3 points  (0 children)

Now turn it around

[–]HedgeRunner 0 points1 point  (0 children)

They are like little trains. 😍😍