This is an I Heart podcast. Guaranteed human. Hey, and welcome to the short stuff. I'm Josh, and there's Chuck and Jerry's here for Dave, and we're just hopping along, talking about kangaroos and how they hop. That's right. Want to thank our old colleague, Kristen Conger, for writing this article for How Stuff Works Back in the Day. And creator of Unlady, like the podcast too. As well as Jennifer Horton wrote another article that I used. Great too. Remember Jennifer. And then take the San Diego Zoo website and Nat Geo all pitched in for this one. I thought this was a particularly well researched short stuff. So I should have known that Jennifer Horton and Kristen Conger had something to do with it. Yeah, so we're talking about kangaroos a little bit. Mainly going to get to how and why they hop. But we should start out by talking about the fact that roos are marsupials or pouched mammals because they have a marsupium, which is a little pouch where their little joeys develop. Yeah, we talked, I think, a lot about this in the naked mole rat episode, where essentially like the marsupial fetus does not develop as long inside the body of the mom as it does inside the pouch. Essentially at some point, it's what you would call born, but really it's just crawling out of the birth canal outside into the world for a second and into the pouch. And then the little joey latches onto a nipple in there. And the nipple grows three times in size, just like the Grinch is harsh. And so the little joey couldn't let go of the nipple even if he or she wanted to until they develop a little further. It's quite ingenious, hats off natural selection. That's a great one. Yeah, that's maybe the fact of the podcast for me. That's kind of nutty. Oh, I'm sorry I took that. I didn't realize that it was. What do I have to always take the fact of the show? I like to, you know. I mean, I know it's in my contract and not yours, but I'm willing to give every now and then. That's very generous of you, thank you. All right, so Australia is obviously what people, you know, what comes to mind when you think of marsupials in general because koalas and kangaroos. But we have done a great episode on the opossum, which live all over the place, especially North Central and South America. But we're talking about kangaroos and wallabies here because they don't have four legs like our opossum friends. They have two big old feet and two little, little or arms. Yeah, that's a great way to think about it. They don't have four legs. They have two legs and two arms. And it makes sense. Like if you've ever seen a kangaroo or you just bring one to mind, if you're capable of using your mind's eye, they're sitting on their feet and they're standing or sitting upright and their little almost titanic arms are just kind of hanging out there, not doing much of anything. Yeah, except boxing probably. The kangaroo, the first sightings apparently traced back to a Dutch merchant named Francisco Pelsert who got shipwrecked off the coast of Australia in 1629. And about 150 years later, they were pretty well known throughout Europe. And by 1791, they had brought those things over to London, England. Here's the fact of the podcast for me, Chuck. Okay. Can I take this one too or should I tee you up? No, double up, baby. So the name kangaroo, the word, as far as anyone is able to say, we don't know for sure, it's apparently an Aboriginal word for I don't know. Isn't that awesome? I don't know. That's pretty funny. It is. Here's the deal though, is kangaroos are the only large mammals to hop. And that's basically as like they're, you know, bunnies will hop a little bit, but the kangaroo moves around primarily by hopping. And I guess you wouldn't consider a bunny a large mammal. Anyway, here's the deal. If you go back to 25 million years ago and look at the fossil record, they didn't hop because Australia was a rainforest at the time. So those kangaroos were climbing around for a long, long time. Yeah. So they actually developed what ends up helping them hop long before they actually started to hop. We call that the fourth toe. If you look at a kangaroo's foot, you can see how it's hopping. And Chuck, I think I've kind of set us up for an ab break and we're gonna come back and finally talk about how kangaroos hop. What do you think? All right, let's do it. Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck, Chuck. We should know. We're learning things when Chuck gets charged. The stuff you should know. Okay. We're left off, Chuck. We're talking about the fourth toe And this is the this is the design element that allows the kangaroo to hop Because if you look at a kangaroo's foot the first toe Looking at the kangaroo's foot from the inside of the foot outward The first toes pretty puny might not even be there the second and third toes They're okay They're like smallish and they each have a nail but they seem to be fused together So like web toes almost like my sister and then when you you get oh, yeah, I didn't know she had web toes Is she a fast swimmer? Yeah, that's what everyone always asks. It's just this the second third toe on one foot or had always been stuck together But surely it would have to give you an advantage to some degree. I don't know. I can't remember the last time I swam with her Well next time you get a chance to race her and let me know how it turns out. All right Finally we get to the fourth toe and the fourth toe is like this is massive beast of a toe and it's in line with the leg bones of the kangaroo's legs and This is where the actual hopping begins. Yeah, that's an actual adaptation And like you said that preceded their ability to hop So I'm not even sure what the deal is with why they adapted that to begin with but I mean Maybe it's just because they went from rainforest to sort of dry grassy plains and they needed to get around more and I don't know Learned it eventually They do have a fifth though we should mention that provides a little bit of support But if you look up Like the the foot of the hind leg like you know from behind They have these really I mean you can't see because it's on the inside But they have these really strong elastic tendons that store energy up for those massive massive jumps Yeah, like a spring when they go downward all of that Tendon gets a bunch of energy kinetic energy stored in it and then when they bounce upward it gets it's released And it can send them flying Chuck. I had no idea how far They can hop and how fast did you? Yeah, but it's always fun to relearn that you know because it's pretty astounding Okay, so they can go up to 15 to 20 miles per hour Yeah, and for those of you in Australia who don't know that's about 24 to 32 kilometers per hour That's fast. That's like golf cart speeds at top speeds even that's faster than a golf cart. Yeah, and then It can propel itself about 25 feet forward almost seven or more than seven and a half meters and six feet high Yeah, nearly two meters high and so it could jump right over either of us Chuck. Yeah, absolutely I mean you're taller than I am so you might get your forehead grazed It could just barely clear me I'm five foot eleven and a half if I'm fully honest. Yeah, they would look at me and just be like no problem Shorty they just free will you right over you? I used to be 510 now. I'm more like 5 9 I'm shrinking as we all do. Yeah, what is up with that? Shrink, you know our but I mean does that mean our vertebra fusing together? Like our knees are getting shorter. Have we compacted the shin bones and our legs and that's what's doing it Doesn't make any sense. Well, we should do an episode like a shorty Maybe on the shrinking as you age because that's it's definitely a thing That's why like you see an old man that has these giant ears. They didn't always look that way. Oh I didn't know that. Yeah Wow, what a development All right, so back to the kangaroo we need to talk about their tails a little bit because they have those huge tails That act as a counterbalance to the hind feet. So if you look at a kangaroo hop that tail moves down Like in midair that tail is moving down to meet kind of where the feet are and when they land the tail raises So it kind of just does this little opposite motion to balance everything out And it makes a really satisfying boring sound. Oh, of course So what's great about this? You said that the kangaroo is the only land animal that or an only large mammal that hops and The reason why it hops is because it's actually a tremendous adaptation for moving quickly Across land in a really efficient manner Because the the way that the the kangaroo is built The bastard they hop the less energy they have to expend. It's a pretty beautiful system. Yeah, it's pretty crazy And one of the most efficient Travelers in the animal kingdom overall you know that like you said they had that great range and Part of what's going on and with their efficiency is is they have a like when they're Bending down to jump and then leaping up that's contracting and suppressing their respiratory system Which actually is like makes it more efficient It makes those stomach muscles contract and expand and just forces air in and out without like having to do so You know by using your own energy Yeah, they also have to use less muscle energy in their legs because when they jump really far high and fast When they land those super elastic tendons that that help them hop Just contract even further and that means that they expand or sproing I think is the technical term even further So when they get going they really can just they can just keep going a while there also their heart is really attuned to this kind of Endurance workout, right? Yeah, it's when they're not going fast when they're just kind of hopping from place to place in grazing That's when it's harder and they have to end up using their tail to kind of balance themselves It's basically like a well a third foot. Yeah Yeah, why does it say fifth in here? That's so weird I know because they specifically said that they're two front arms, you know Hey, well, maybe I'll get in touch with Konger gives me a good reason to get in touch with her So what the hell did you mean this fifth leg thing all those years ago? You're gonna ruin her week. She's like who is this? right, I Guess we'll close quickly just on a little you know I mentioned the wallaby The the slight differences between the wallaby and the roux Mainly it's the kangaroo is just a lot bigger They have a lot more length between their ankles and their knees and they're just taller They can be like eight feet tall whereas a wallaby Maybe like three feet a little over can you really say it any other way than that? I don't think so. I mean, why would you anyway? Yeah, this is probably long after your wheelhouse, but did you ever watch Rocco's modern life? Never heard of it It's a great cartoon Yeah, it's a cute little cartoon. It was on Nickelodeon and Rocco was a wallaby. Oh nice Did you ever watch Darkwing duck? Never heard of it. No, that's not it What was the duck with Jason Alexander as the duck? Oh, I don't think I I don't think I know of such a show It was like a raunchy Com like superhero duck show that was pretty good Whatever the name of it was look it up Jason Alexander George and Seinfeld played the the main duck. Oh, well, that was a good one, too Yeah, I think Darkwing duck is like a duck tails spin-off. That's not what I'm talking about All right, well, I mean if we're recommending animated shows I might as well and we're in Australia I got to recommend Bluey again still watch that Okay, I never watched that one. Yeah So so stepping out of the animated shows but continuing with the recommendations. Oh boy. Here we go The Jake Gyllenhaal movie Enemy last night. Oh, yeah, it was Denis Villeneuve Have you seen it? Yeah, so I back back then Man, it is a good movie. Yeah crazy ending Yes, but so like it was one of those movies that I was like just sitting there thinking about it afterward Yeah, yeah, and so I love those because if you go look them up online There are people who have like given great thought to explaining these things and I found I think on a slash film A really great explanation of what was going on But before warned if you watch Enemy you may regret reading The explanation of it. It's almost to me It was better before I knew and I just had had to accept it on its own terms. Yeah, love that movie All right Well, that's it for Enemy and that's it for obviously kangaroo hopping right? That's right short stuff is out Stuff you should know is a production of iHeartRadio For more podcasts my heart radio visit the iHeartRadio app Apple podcasts or wherever you listen to your favorite show哎哎
