5 Animals That Have Bone Skin

From the long extinct Stegosaurus, to tiny modern mice, all sorts of animals grow bits of bones inside their skin. These structures are called osteoderms, and they're often more than just a suit of armor.
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[@Totalinternalreflection]

I'm not crunchy on the inside, I'm entirely made out of jelly and 4 different mental illnesses.

[@NeuroKytsh]

nice profile picture

[@barth9580]

Are you my ex?

[@artgreig7069]

Just four? Novice!

[@lemagicbaguette1917]

This guy is the Mental Megazord.

[@doyouwanttohaveabadtime7521]

What kind of jelly?

[@jimcappa6815]

I appreciate the use of the highly technical term "sticky outy parts!"

[@kyrab7914]

Likewise bone skin

[@karinwolf3645]

Me, too!! 😆😆😆✊💋💖👵🌵🐺

[@aldenconsolver3428]

High marks to the researchers who studied osteoderms on very gravid alligators.

[@corwinweber693]

They're bad enough when they AREN'T pregnant.

[@AlienShuttlecraft]

Meth Lab! I love that dog!!

[@melodyszadkowski5256]

I second that. Whoever thinks pregnant women are weird, you should meet a pregnant alligator.

[@xthieryx]

Ovulating isn't the same that being pregnant (although it doesn't mean one shouldn't be extra-careful along a ovulating alligator or any alligator 😅). Not sure about alligators, but animals like chicken can ovulate without copulate. That's all the reason why we can farm eggs and mostly of the time we don't find a dead body inside it.

[@howlinghellgar2214]

@@xthieryx Most animals that ovulate do so without needing to copulate as far as I know. Humans are a prime example, and I’ve personally handled cats (well, one cat) and horses in heat before. You’re definitely right about needing to more careful though, they get hormonal just like we do 😅

[@Erik-pu4mj]

Savannah is easily one of my favorite speakers on KZbin. Every part of their presentation feels right. Thank you for bringing us more science!

[@zuglymonster]

Rodent tails have always been so weird to me. They look so weird with their little sections

[@kiwik2951]

Reminds me of worms. Have you ever touched one?

[@ezachleewright2309]

​@@kiwik2951I touch worms when it rains cuz I don't want them to fry on the sidewalk later. I just toss them into the grass tho

[@okayyish]

​@@kiwik2951 I own rats, their tails actually feel more like snake skin! It's super interesting

[@lakrids-pibe]

Are squirrels rodents?

[@TheKateO13]

@@lakrids-pibe yup.

[@Respectable_Username]

Just wanna say how much I love Savannah's energy in both the videos and Shorts! Always in for a fascinating time when their face pops up 😄

[@karinwolf3645]

She's great, isn't she?? 💋💖

[@GandalfTheTsaagan]

Osteoderms are very cool. They're also covered in extensive sheaths of keratin, like claws and horns. The Borealopelta ankylosaur "mummy" that was found not too long ago was so well preserved that it had such keratin sheaths.

[@melvinshine9841]

Pretty sure giant ground sloths had osteoderms as well. Which makes some sense as they are in the same group of mammals that contains armadillos.

[@seanathanbeanathan]

The way you phrased this sounds like you're pretty sure the giant ground sloth you met that one time had them, but your memory is a little fuzzy 😂

[@calcaware]

This sounds awesome. Is it true? Sources?

[@melvinshine9841]

@@calcaware After some looking, we've known osteoderms were a thing in ground sloths for over a century, and there are actually some examples of mummified ground sloth skin with intact osteoderms. There's at least six species I could find that had them, but sadly Megatherium probably didn't have them.

[@gbazo762]

Humans have one of these in our neck

[@aazhie]

​@@gbazo762you talking about the Hyoid bone?

[@darleenross710]

The writers of this show are so awesome. The lighthearted way info is presented makes the subject matter totally interesting.

[@_maxgray]

I love Savannah's energy, they are so delightful in their enthusiasm!

[@icarusbinns3156]

I honestly enjoyed the image of her cradling all that soda!

[@WingedAsarath]

​@@icarusbinns3156 (just a heads up, Savannah goes by they/them)

[@queens.dee.223]

Savannah is such a delight as a host. I love seeing them.

[@TonyMarselle]

Reminds me of pat

[@ptszymanski]

💀

[@monk607]

Hard agree

[@EuropaE]

Savannah knocked it out of the park with this video. Their personality and sense of humor adds so much to their delivery of the information. Kudos!

[@tjcasper777]

To me, what makes SciShow are its wonderful hosts. They really have an embarrassment of riches when it comes to them.

[@Meh-qe4rw]

Butwherearethegapsbetweensentences?It'slikeonelongverbaldiarrhea.NowonderpeoplearegettingADHDlol. - SciShow *edit

[@karinwolf3645]

Oh, but I really like them!! 💋💖💋💖👵🌵🐺

[@_andrewvia]

@@Meh-qe4rw Their inhaling is edited out to make the video shorter. Every second makes a difference on yt, apparently.

[@raraavis7782]

​@@Meh-qe4rw Yeah, I hate that as well. Have gone from a regular to a very occasional viewer on many channels like this, because I find 'spitfire delivery' and sentences without breaks extremely exhausting. I'm interested in the content, but this style just doesn't work for me.

[@BGBigMax]

I agree completely. She's my favorite host by far!

[@jessicas.6235]

Savannah is such a cute person❤ It’s crazy that we’re still learning new things about the extant animals around us.

[@greenman6141]

My first time seeing this host, and I am so impressed! Great talent. Great persona. Great communication skills.

[@ArmyCop]

Savannah has rapidly become one of my favorite hosts here. They have a wry delivery of the light-hearted asides that are written into the script. (e.g. When holding the two-liter bottles of cola, saying (seemingly to themself) ‘These are really heavy!)

[@huldu]

I had spiny mice as pets when I was young. The males were very relaxed and comfortable around each other and regular mice they even shared a den without problems. However the spiny mice females were *very* aggressive. I thought it was such an unusual behaviour they could start a fight with another spiny mouse female(or males) and it would be a fight to the death. We had to split them up in several cages because of this weird behaviour. Not all females were like that though but it felt like as they got older they got very aggressive. I'm thinking it might have been a territorial behaviour?

[@sayno8685]

Ohhh thats new for me, males are usually the territorial one, yes?

[@jeanjaz]

Parakeet females are the bossy, bitey ones, where the males are more laid back and affectionate.

[@Ryan46]

Spiney mouse Karen's

[@icollectstories5702]

The Housewives of Spiny Mouse Land

[@daniell1483]

I've always been fascinated by osteoderms ever since I learned what they were in crocodilians. Really neat dermal armor!

[@heathernicol3026]

“Face to… well, not-face” XD

[@Renisanxious]

Ive never heard of a humans insides being described as crunchy 😭

[@chimeraproject9481]

I kept reading "spicy mouse " God, help me😢😢😂😂😂😅

[@MoosieFilms]

This is the best comments section I've been to all day and it's nearly 11pm. Just lovely people being excited about science ❤

[@kray3883]

And the tail bone's connected to the...skin bone.

[@elianadrew1964]

So well presented I am requiring my students to watch it! Thanks 🙂

[@brfisher1123]

The animals of this list are all one specific group of tetrapods called amniotes as no amphibians were mentioned so maybe osteoderms are an amniote thing.

[@malicious-fisheeves]

I do believe temnospondyls and some other ancient amphibians may have actually had osteoderms!! Not modern ones tho 😔

[@mrnonamekid4030]

I would imagine that bony skin would make it harder to breathe through said skin

[@kyrab7914]

I believe they mentioned amphibians having them, which I was curious about bc yes that's unusual

[@93lozfan]

I was wondering about my sand boa's tail. i thought it was just rough keeled scales but having bone in there makes just as much sense I guess.

[@tysonessenmacher2091]

The bone plates on the stegosaurus were to prevent smaller dinosaurs from jumping on its back, where it would be safe from teeth and tail, and chewing a hole through its spine.

[@ZombieBarioth]

That would definitely be a plus, along with making themselves look bigger and more threatening. They may not hold up well against larger predators but it would still make them think twice. A herd of stegosaurus together would look something like rows of palisades that swing back.

[@thehellyousay]

And exactly how would you know that? Or are you just pulling s**t out of your arse and trying to convince us it's chocolate, hmmm?

[@ldmtag]

Prevent? Maybe... but... Wouldn't it actually make it easier to grip and stay there?

[@a_e_hilton]

SciShow's here with the wildest titles you've ever read recently omg

[@YuBeace]

I love how they had to carry all this soda to make the point.

[@Mike28625]

It makes sense for that snake to use it's tail to activity fight anything bothering it's back side.

[@Zappygunshot]

Another use for osteoderms, and the skeleton as a whole, for all reptiles, is to help metabolise their food. For one thing, unlike humans, their stomachs aren't always full of acid. Being cold-blooded animals, reptiles don't need to eat nearly as often, so not constantly having to produce metabolic enzymes all the time saves even more energy and resources. So they only flood their stomachs with acid when they've just swallowed a meal. Once it's digested, however, they're stuck with a sac full of organic solvents that could cause trouble if left unchecked, so they neutralise that by pulling calcium and magnesium from their bloodstream, and if times are tough and the animal hasn't had any calcium-rich foods like eggs or vertebrates recently, they can eke out a little extra time by using some of the nutrients in their own bones. For another thing, reptiles need to use calcium to metabolise vitamin D, and to metabolise calcium, they need ultraviolet light. This is why, shortly after a reptile has eaten, you'll see them finding a nice little basking spot to soak up those rays - they wouldn't be able to acquire all the nutrients they need otherwise. Now because reptiles will use the calcium stored in their bones to compensate for a nutrient-poor diet or lack of UVB light, it means that being unable to fulfill those needs for prolonged periods of time - especially while the animal is still growing - can lead to their bones becoming softer and deforming as a result. This is called metabolic bone disease (or MBD for short), and is both extremely painful and impossible to fully cure. After all, once your bones have grown wonky, they can't exactly un-wonk themselves, even if you do improve your diet. MBD is probably the most common disease in pet reptiles, because it requires a little bit of knowledge about just how differently a cold-blooded animal functions compared to us warm-blooded humans, and sadly many people buy pets on a whim because of cool or cuteness factors (or to shut the kids up). Many reptiles make for great pets, but only if you do your research before you buy them

[@TastyChubz]

Gotta admit. Changing the thumbnail from a caiman to a mouse definitely made me finally click this video lol.

[@TheWhitefisher]

Appreciate the positive, educational content! You're helping me out of my true crime rabbit hole! Oh yeah--science!

[@KrazyKaiser]

On the Stegosaurus: When any feature in an animal is exaggerated to the extreme extent of the Stegosaurus's plates, the probability of the evolutionary factor of that being "They thought it was sexy" greatly increases.

[@Little.MissDiagnosed]

Savannah always has the kickiest shirts. Their fashion is as good as their presenting!

[@jacklandismusic]

I love translating Latin words into English. Bone skin. Wing fingers. Head foot. Breast tooth.

[@Beryllahawk]

Great video! Very interesting to understand just how many OTHER functions the osteoderms have beyond armor! Also had a good giggle at the three-and-a-partial bottles of soda, not least because I know exactly what brand those are, hehe AND because they really do get heavy quick! (my son has a bottle of that root beer, as I type this; he's not a teen anymore but man can he make soda vanish like one)

[@pommydiva1]

on this channel you learn something new every day. i never new about this bones on the outside. wow.. thanks for the vid

[@paulkinzer7661]

Savannah, I love your presentation here! Keeping it fun makes it more pleasant to watch. Also, 'skinbones' is my new favorite word. Band name?

[@safaiaryu12]

Love how they illustrated with soda, lol. I genuinely didn't process how much space they were talking about until they were holding the soda; that's some good writing/education right there! Anyway, animals are so much stranger and cooler than we realize. Science is finding new stuff all the time, and that just delights me.

[@jasonwebb1882]

What about my little buddy that is sorta like an armadillo, the Pagolins? I know that lions have a very hard time getting inside to that chew crunchy part. But I guess the Pangolins armor is like a Rhinos horn. Time to do a little research to find out. Lol. Take care and just know that I wish you all the very best that life has to offer. Peace out.

[@joanhoffman3702]

Pangolin scales are made from keratin, just like rhino horn. The resemblance to the armadillo could be convergent evolution. Both critters try to keep predators from their soft, chewy center, which is the goal for all prey species. 😂😂😂

[@AuntieShanti510]

Yup. Even after ten minutes of hearing it the term skin bones is still creepy.

[@thehellyousay]

Bone skin. That sounds metal, don't it?

[@hectorskmetija3015]

I found this presenter easy to listen too and had me hanging on their every word. Would like to see more videos with them 👍

[@nariu7times328]

love this show!

[@deathm3lon642]

A removable skin sheath is beautifully well worded

[@Alice_Walker]

This is a very cool episode! 💜

[@dracodracarys2339]

ankylosaur-on-ankylosaur conflict sounds kind of metal. like we always see them depicted using their clubs against predators but seldom against rivals of their own species. imagine the noise of clubs whacking into one another

[@aquaticcatfey]

Okay, but Savannah is adorkable.

[@chloesibilla8199]

Thank you for crediting the photographers!

[@Phlowermerchant]

Hell yeah, armadillos

[@scottmoore765]

I always enjoy her commentary and perspective on science.

[@Dash-NinjaFerretArt]

*their

[@Reyma777]

An extinct group of ground sloths known as mylodonts had osteoderms in their skin.

[@starwyvern010]

That was super cool!

[@MyVanHaven]

Still my favorite presenter, love their jokes and choice pauses lol

[@emdale9269]

Love this host!

[@TheAdvertisement]

"We humans might be crunchy on the inside" ok so this is how we're starting this

[@bytesandbikes]

This can happen to humans too, albeit very rare (most often in the forehead, cartilage is much more common than bone, but still rare)

[@mickaelb.farlay2514]

Aren't pangolins also covered in osteoderms ?

[@thekaxmax]

no, that's keratin, like fingernails.

[@WingedAsarath]

While it may not have aged the best in terms of the science, since paleontology has progressed so rapidly over the last couple of decades, it seems Walking With Dinosaurs did a good job on showing stegosaurus using its plates for display.

[@swampcooler8332]

Im not crunchy on the inside, im crunchy on the outside and sloshy on the inside

[@derlebkuchenmann]

The host made this amazing. What a cool and captivating episode.

[@Boydus1]

Crunchy on the outside, smooth on the inside, armadillos

[@Nylak-Otter]

Sounds like thick soup in a crisp bread bowl. Delicious.

[@ldmtag]

Whenever archaeologists don't know what the thing they found was used for, they say it was for cult. Whenever paleontologists don't know what the feature of an extinct animal was used for, they say display.

[@TheInselaffen]

Everyone in Britain knows that armadillos are crunchy on the outside, smooth in the middle.

[@deborahbloom4624]

I love the technical description "stickie outie parts"....😂

[@shatterthemirror8563]

Me too the crock: "I met you in a past life."

[@travvitz]

Omg i am a research technician in a lab with spiny mice!!

[@oblivionpro69]

I saw an armadillo in East Tennessee a few weeks ago, those little guys are movin north.

[@Ice_Karma]

Does anybody else find that the whole "brain bleach" thing, like our host describes at the end of the spiny mice segment, doesn't actually work for them? 😿

[@Dash-NinjaFerretArt]

I find that I can sometimes distract myself, but a really vivid mental image isn't going anywhere.

[@ogfoxhound]

Very old observation. While feeding my burmese python once i had a very squirmy rat slide right out out of my hand and i was left with a probably 2-3" tail-skin-sock in my hand and a jumbo rat running around our room. Not definitive but you mentioned exactly that. I wonder if feeder mice/rats might occasionally develop, already have osteoderms on their tails, or might be able to slough that skin off easily regardless. Thats wild. Probably 8-10 years ago that happened, never thought about that. Once we get our @journeytomicro microscope, we'll do our best to report in.

[@_andrewvia]

Yay Savannah!

[@tiffanymarie9750]

Always makes me think of Elvi in the Expanse talking about good moves in design space; and makes me wonder what might be evolving out in the wider universe. So far, I'm pretty sure most macro life is gonna be either trees or crabs or both somehow

[@ldmtag]

I'm not sure. I think the most common body type in the universe might even not be present on Earth. Not because I have something specific in mind, but simply because it's not enough to just have the selection pressure towards obtaining the ideal shape, you need your genetics to be capable of doing that shape. Lives on other planets might've gone so vastly different paths with so many other shapes. What if they have something, like, idk, pokemon Ditto that can transform into anything (I don't mean literally transform, but, like, reorganise its joints)? Or what if they have something small, tanky, with big brains, that can also levitate in thick atmosphere, takes pressures ranging from Venus surface to Mars surface, and is somehow made of solid rocks or metals? What if their regular carbon life adapted, like, titanium or aluminum for their skeletons/exoskeletons, and they're super lightweight and super durable? Who would need to be a low mobility crab, if you can handle some serious speed and maneuvreability?

[@noobynoob138]

hey! my bones are on the outside too! (please call an ambulance)

[@lexslate2476]

Great now I am sad about not having osteoderms.

[@jakegarvin7634]

2:30 - you and Clint from Clint's Reptiles would get along famously

[@pjenestratsienatie1876]

Aspidelaps scutatus is a weird one I have personal experience with, and i think they are also a snake with osteoderms in its tail due to them having protruding bulbs on their tail. Their closest related species the lubricus does not have these.

[@Pringlulz]

I definitely skipped past this video with the other thumbnail but seeing a mouse with that title got me curious.

[@CL-go2ji]

+

[@dwightehowell8179]

I have been told that ground sloth had small bones in their skin. I have no first hand knowledge of this one way or the other.

[@adpirtle]

I saw no spectacles on that caiman.

[@popcorn200213]

I fully thought "bone skin" was going to be talking about periosteum and I was like "DO NOT ALL ANIMALS HAVE THAT?!?!"......They meant Bone-skin...

[@nicholasrapacciuolo8561]

Caught this upload early

[@queeny5613]

Awesome

[@Nylak-Otter]

I have bone plating on my skin, they're just not *my* bones.

[@BlastTheBat]

This reminds me, Arabian Sand Boas. They are so derpy looking.

[@intimeoflilacs3528]

I love this host 😂 they cracked me up during this video

[@rrteppo]

I'm pretty sure we have some floating ribs that are not quite attached as well as you would imagine.

[@dillonrose3428]

Hell yea for skateboarding 🤘🏼🤘🏼😎

[@weaselwolf]

The joke amongst paleontologists is that if you don't know what it's for, just say it's for thermal regulation or mating display. Sort of like the joke amongst archeologists that if you don't know what something is for, just say it's ceremonial.

[@brocktonjaycc]

Just came here to say: way better thumbnail than the crocodile!

[@ginnyjollykidd]

Humans are tetrapods, too. The bone in the skull comes from 2 sources: cartilage-derived bone form the inner skull structures. The outside of especially the brain case originates as dermal bone.

[@augustlizabethmoore]

😂😂😂 I thought it said "Sand Beans", I love it so much 😂😂😂😂

[@ianmacfarlane1241]

I've got skin on my heels with could pass for bone.

[@samanthaelizabeth8330]

I like Savannah a lot!

[@onyxianna]

I like to think of my teeth as osteodermal tissue. I know, but still it helps me feel closer to my favorite animals

[@lyndsaybrown8471]

Armadillo doesn't imitate tanks, tanks imitate Amarillo.

[@jakobsmith1396]

Wait, what? If the mouse sheds it's tail skin like a glove, and can't re-grow it's tail but has an exception ability to regenerate skin, muscle and nerve cells... why on earth would it then chew off the rest of it's tail once it's away from predators? Did you mean that it chews off any remaining skin that didn't manage to fully come off while escaping the predator, or did you genuinely mean that it just straight up chews the tail off?

[@TheArnoor]

You missed one of my favorite's, some giant sloths also had osteoderms

[@aick]

Careful what you wish for... my plaque psoriasis gives me gross, boney plates on my elbows.

[@CL-go2ji]

On the one hand: sorry and may you have mild plaques. On the other: wait, are they actually OSSIFIED? I always thought those were keritin.

[@qarljohnson4971]

Would land tetrapods ability to evolve osteoderms be a genetic relic of the ostracoderms of the Silurian/ Devonian period?

[@mathmusicandlooks]

The sand boa’s tail sounds like a great example for “survivorship bias” in real world evolution…