Why Some Animals Have Quills and Others Have Spines

In this episode, Rick explores the fascinating world of quills and spines in mammals, debunking myths and explaining the differences between various species like porcupines, hedgehogs, echidnas, and tenrecs. Discover how these adaptations evolved and their unique functions in animal defense mechanisms.

Animals Nature & You on Instagram: @AnimalsNatureandYou

Connect with Rick:

ZoologyRick.com

Social media:

Instagram

Threads

Facebook

YouTube

Music: Positive Carefree Folk Pop

Artist: Burgberg

Used with Full Music Standard Lic.

Transcript

SPEAKER_00 0:00

If I got this right, porcupines can shoot their quills, but hedgehogs can't, because hedgehogs have spines, but the spiny anteater, which is actually an echidna, not an anteater, doesn't have spines, has quills, but then the tenrec, which is sometimes has hedgehog, and the name isn't related to hedgehogs, but looks like a hedgehog, has smaller spines or spikes or quills or prickles, but it's related to the elephant or the artvark, but not the hedgehog. I'm Rick Schwartz, educator, public speaker, and all-around curious guy. Over the years, my curiosity and experiences, along with the many people I've worked with, revealed to me we all have a desire to feel connected to the natural world. You're listening to Animals, Nature, and You, a podcast that explores the connection between animals, nature, and humans. A podcast that celebrates learning more, following our curiosity, and reconnecting with the natural world. It's another 10-minute Tuesday here on Animals, Nature and You. I'm your host, Rick Schwartz. And like many of the 10-minute Tuesdays we've already had, this episode is inspired by the episode we just had last Thursday, an interview with Stephanie Arnie. You don't have to listen to that interview if you haven't already to know about what we're going to talk about, but it helps. It gives you context as to how that episode inspired this one. In that episode, in that conversation with Stephanie Arnie, we brought up porcupines. She shared a story about how she realized the importance and need for wildlife education because she saw how baby porcupine was being treated by people who had believes that porcupines could shoot their quills, uh, do all sorts of damage, a lot of fear-based beliefs around a myth when the truth is they can't shoot their quills. Quills of a porcupine are just a modified hair. So how does that myth come about? Well, in today's episode, I want to talk about quills and spines and the different mammals that have these things and how they got their names and which one means which, or is the name interchangeable? So let's start with the North American porcupine. The North American porcupine's quills are very shallow rooted hairs or modified hair. In fact, all quills or spines in mammals are a modified hair, growing out of a root follicle, some deeper than others, and the modification of that hair is different depending upon the species. For the North American porcupine, the quill is loosely rooted. It's a very shallow root. If you were to look at the quill, the majority of it looks like a nice long needle, and the very little end that is not the pokey stabby end, the end that goes into the animal is a very shallow root follicle, made of keratin, just like our hair. If you hold the quill by the root and run your fingers towards the tip, you would feel very rough, jagged edges. These are the microscopic barbs or hooks, they're not true hooks, they're more like a barb, if you will, because the way the quill grows. Think of uh tightly laid shingles with sharp edges. And so as you run from the root towards the tip, it would hook and pull. So when the quill goes into the animal that's trying to attack it, the dog that's trying to sniff it, whatever it might be, the quills easily sink in, they're super, super sharp. In fact, studies done to show that it is sharper than and goes into the flesh easier than an 18-gauge needle, which you would use for a hypodermic needle for like a vaccine or a shot needle, same size as the quill, the quill goes in easier. The thing is, those shingles or those hooks, the barbs, if you will, they anchor it in there. And so as the animal pulls away from the poke or the stab or the jab, the root follicle is so shallow, it comes out very easily. Again, this is a North American porcupine to just give us some context here, some ground rules about what we're talking about with a quill. Now, here's a fun fact for you. If you know somebody who has hair much longer than mine, so long hair, if you hold it by the root and run one direction and run the other, you'll feel on the human hair, because the way the hair grows, there's a rough direction and a smooth direction, depending upon which way you go. So fun little fact for you. So if quills and spines on mammals are modified hair made of keratin, we know the North American species has those barbs or hooks or the layers that create the ability for it to sink in very easily. What about all the other ones out there? What about the spiny anteer? What about, also known as the echidna, what about the hedgehog, the tenric? What about the old world porcupines, the crested porcupines? Everybody's a little bit different. It's interesting. I've had the great pleasure of working with North American porcupines and also crested porcupines, and echidnas, and hedgehogs, and tenrics. Not all of the many different species out there, but some of each kind, as far as the tenrix, hedhogs, and all those guys. Here's what I know from my personal experience. When I first got into wildlife education, I'm working with these animals, the question came up: are they spines or they quills? Is it interchangeable? I did some research and let me rephrase that, scientific research is very different than just looking stuff up. I looked some stuff up in a lot of different resources of scientific research that was already done, and I looked at that information, came away with the fact that a quill is considered hollow, where a spine is considered solid. So one extreme would be if you take a North American porcupine quill, cut it with scissors, you would see it looks like a straw inside. This gives it a lot of strength when being poked, but it can be bent pretty easily if you take it tip to tip and bend it. You look at the echidna, if they shut out a quill or a s uh one of their spines, depending upon what you want to call it, and cut it in half, it's very almost like styrofoam inside. There is a cord to it, but it's spongy. If you take a hedgehog quill or spine and you cut it, it is solid. So by the definitions done by scientists that came along much earlier than me, the quill of a North American porcupine and the quill of a crested porcupine, the quill of a echidna, an echidna, and then the spine of a hedgehog and the spine of a tenric. So that goes into the tenric and the hedgehog, although not related, they have grown quills or spines, spines that are solid. They're shorter and very strong. They are deeper rooted, they don't come out easily, they don't have the ability to come out like the other quills do on a porcupine. Tenrix, interestingly enough, some species, theirs are so deeply rooted in a certain muscle tissue, they can vibrate them to create sound. The hedgehogs in general don't lose their quills, and although hedgehogs and tenrix are not related, they use their their sorry spines. They use their spines in a very similar manner and balling up to protect themselves. And instead of those sharp, pokey, stabby, keratin-based, modified hairs coming out to poke into and stay into the predator, they're just a really hard thing to open up that doesn't really feel very good to chew on or paw at. So hopefully the predator leaves them alone. Whereas the North American porcupine, like we discussed earlier, they, their quills will come out and embed in the face of that animal, trying to sniff them or bite them or grab them or at a paw. So if you've ever had a dog come home with quills in its face, it looks like they were shot. Two reasons for this. The long hairs of a North American porcupine are guard hairs. They act like whiskers. So when a dog comes up to sniff them, dogs like to identify things by sniffing, dog comes up to sniff them, the porcupine's gonna feel that and jump towards what's touching it, forcing the quills into that face. The dog pulls away the face full of quills that are now embedded and very hard to get out. And if the dog doesn't learn his lesson the first time, it decides to go in for a second sniff, it's just gonna happen again. Or then the pause, they start to do this, trying to get the quills off their face. If you're not watching on YouTube, what I just did was basically moving my hands in front of my face, trying to get the quills off the face and off the muzzle, they can embed some of those quills into their forelimbs, again, giving more of that illusion that it was shot out of the animal, out of the porcupine, into the dog. Now, we talked about the much bigger crested porcupines. These are old world porcupines, and there are a lot of different species of porcupines out there. They are rodents, there's all sorts of different kinds across Africa and India, Asia, Europe, here in North America, even in South America as well. And everyone's quills are a little bit different. But I have I've worked with uh the crested porcupines. They're interesting in that they have modified hairs that are very long to give them a crest that are stiffer than a standard hair. It would be like if you put a lot of gel in your hair and slicked it back. But they have the ability to move those to make themselves look bigger. And same with the quills of their lower part of their body, they have the longer guard ones, but underneath are the really stabby ones. Their quills, depending upon where it's located on their body, can be like a very sharpened pencil or it could be almost blade-like, like a saber, where I've seen some that are ridged and sharp and come to a flat tip. So again, going into that animal to defend itself, a leopard, a lion, something like that, hyena, those are going to go in deep into that powerful, strong flesh of that animal. So it's interesting to see how these different adaptations for this quill slash spine, depending upon what species you're talking about. So again, for a quick review, we tend to call quills in the biological, zoological world. Quills tend to be hollow, where spines tend to be solid. That middle fuzzy ground is the echidna, also known as a spiny anteater. Most stuff I looked up right now, most zoologists consider their modified hair that's sharp at the end to be a quill, even though it's filled with spongy material. They consider that hollow in comparison to the hedgehog or tenric, which is solid, almost like a nail, if you will, where it's that thick keratin all the way through. I'll let you decide, or maybe you know more than I do. If you work with porcupines, echidnas, tenrics, hedgehogs, you tell me. Leave a message here on YouTube in the comments or reach out to me on social media. There'll be a post on all of my social media about this episode, so you can engage there if you know more or have questions about quills versus spines when it comes to mammals. Now, of course, sometimes we use the word quill. We talk about the shaft of a feather of a bird, you know, quill pen, that hollow tip, spines sometimes in different marine life. The the uh sea urchin has spines. So there's different things, and then the horticulture world, the botanical world. Any botanical friends out there, there's thorns, there's spines, there's spikes, there's all sorts of stuff, isn't there? And that's not my realm, not my realm at all. Either way, I'm gonna wrap this up right now, and I do want to say thank you so very much for joining me on this curious odyssey here on Animals, Nature and You. If you haven't already, I want to remind you to subscribe or follow depending upon where you're watching or listening to this podcast. Animals, Nature and You has new episodes coming out every Tuesday, like this, the 10-minute Tuesday, which is a shorter, solo episode. And every Thursday, I do an interview with an awesome person doing awesome things, and we get to talk to them, learn about them, how they got started, what they're doing, and how it's changing the world for the better. Or just changing the world for animals, or just changing the world for humans, or maybe animals, nature, and you. All right, with that, I'm gonna sign off. Have a good one, everybody.