Pod Insights Radiolab The Builders About this episode In an episode first aired back in 2025 on our sister show, Terrestrials, we take you on a musical journey all about beavers. Few mammals have a bigger positive impact on the planet than the beaver. With its bright orange buck teeth, the creature is an expert engineer that brings life wherever it waddles and even fights fires. Our story begins in the Bronx river, once known as the “open sewer” of New York City. After some humans decide to clean it up, we meet one of the river’s residents - José the beaver. We learn about the US government parachuting beavers out of planes into the mountains. And finally head to California where we discover how one beaver family saved acres of land from burning.
Transcript 0:01 Speaker 00 Hey, it's Latif. Earth Day is coming up on April 22nd. So this week, I wanted to bring you a story that is just a wholehearted celebration of nature from Radiolab's spinoff, Terrestrials. We released it last fall in the Radiolab for Kids feed. But look, I am a card-carrying grownup, and I really enjoyed this one. And I think you will too, no matter how young or old you are. Lulu will tell you more in a second. So, without further ado...
0:34 Speaker 01 Wait, you're listening?
0:35 Speaker 02 Okay.
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0:39 Speaker 01 All right.
0:40 Speaker 03 You're listening to Radiolab. For kids!
0:44 Speaker 01 Radiolab.
0:45 Speaker 03 From...
0:46 Speaker 01 WNYC.
0:48 Speaker 02 See?
0:48 Speaker 01 Yep.
0:54 Speaker 03 Three, two, one. Imagine...
0:58 Speaker 01 You wake up in the dark.
1:01 Speaker 03 Your eyes dart around to see...
1:03 Speaker 01 A little circle of blue shimmering light.
1:07 Speaker 03 You waddle over on your webbed feet and realize it's water.
1:11 Speaker 01 So you dive in, headfirst.
1:13 Speaker 03 As you kick and glide, you grow fur.
1:16 Speaker 01 Really thick fur.
1:17 Speaker 03 And an extra set of eyelids.
1:20 Speaker 01 That act like goggles underwater.
1:22 Speaker 03 And then you look behind you to find...
1:24 Speaker 01 A big, black, scaly paddle.
1:27 Speaker 03 It's your tail, which you can slap on the water with a nice, loud... You have become...
1:33 Speaker 01 A beaver.
1:38 Speaker 03 Okay, now is the part where I make you sing the theme song with me.
1:41 Speaker 01 Okay, I'm ready. Terrestrials, terrestrials. We are not the worst, we are the... First.
1:51 Speaker 03 Try again, opposite of worst is?
1:54 Speaker 01 The best. Bestrials.
1:56 Speaker 03 Yeah, you got it!
1:58 Speaker 01 Okay, I like it.
1:59 Speaker 03 Terrestrials is a show where we uncover the strangeness waiting right here on Earth. I am your host, Lulu Miller, joined as always by my song bud...
2:05 Speaker 00 Take me to the river.
2:06 Speaker 03 Alan. Swimming with the beavers.
2:10 Speaker 03 So here we are kicking off this brand new season of Terrestrials. Well, all around us, really hard things are going on. Wildfires, wars, climate change. And so we wanted, in this moment, to look to creatures that might give us hope. Creatures that actually mend the world around them. And there is maybe no mammal that has such an outsized positive effect on the planet than beavers. Yep, those buck-toothed, waddling, funny-looking rodents. By the end of the episode, you will see how a single family of beavers can have such a positive impact on the world around them, you can literally
2:55 Speaker 03 see it from space.
3:02 Speaker 03 So our story today is going to center around one little beaver named Jose. He will rise out of murky waters in a place where no one expected he could survive. And to tell us his tale is producer Bud Anna.
3:16 Speaker 04 Yep, that's me.
3:17 Speaker 01 Yeah, you know, Jose is this incredible symbol.
3:22 Speaker 04 And here to help me is Ben Goldfarb, who's a writer.
3:25 Speaker 01 And beaver believer.
3:26 Speaker 04 Don't stop bee believing. So Jose, he waddles out into the world with little webbed feet and whiskers and very large buck teeth that are bright orange. Because apparently...
3:40 Speaker 01 Beaver's teeth actually contain iron.
3:43 Speaker 04 Whoa, metal teeth?
3:44 Speaker 01 Yeah, like a chisel.
3:47 Speaker 04 The iron makes their teeth excellent for chopping down trees. Because beavers have one single obsessive hobby. It's not drawing or knitting or doing puzzles.
3:58 Speaker 01 The classic beaver behavior that most people know about is they build dams.
4:02 Speaker 04 A dam is basically a wall in the water that beavers build by dragging the trees that they chomp down across a flowing stream, blocking the water. And sometimes adding mud or other stuff to keep that wall sealed up tight.
4:16 Speaker 01 And you see them sometimes carrying rocks around and their little front paws waddling on their hind legs. It's like the cutest thing ever.
4:23 Speaker 04 A beaver dam makes water accumulate behind the barricade, turning a trickling stream into a new pond in the middle of the forest.
4:32 Speaker 05 Ah, time for a shrimp.
4:34 Speaker 04 Anna, can I just interrupt to ask why? Like, I've always wondered this about beavers. Like, a beaver like Jose, why is it driven to go through all this work to chop down trees and make a wall that creates pools? It just feels so random?
4:48 Speaker 01 That's a great question. There, I mean, a beaver out on land is basically a fat, slow package of meat. Think about wolves and mountain lions and bears and coyotes. All of those big animals are gonna want to eat a beaver.
5:05 Speaker 04 According to Ben, it all stems from the fact that beavers are super awkward on land. With their webbed feet and huge tail that drags on the ground, beavers are not good at running, making them easy pickings for land predators.
5:20 Speaker 01 So if you're a beaver, you want to spend as little time on land as possible.
5:26 Speaker 04 So?
5:31 Speaker 04 By making dams, they create deep pools of water, which allows them to transform from wobbly wolf snacks into elegant professional swimmers who can spin and twirl and...
5:42 Speaker 01 Can hold their breath for up to 15 minutes.
5:44 Speaker 04 15 minutes?
5:46 Speaker 01 Yeah, they're like a magical animal. Yeah, they're just incredible.
5:50 Speaker 04 Pretty epic hiding place. Now, hundreds of years ago, in the time of Jose's great, great, great, great, great, great, great grandparents, the woods of North America was full of beavers.
6:03 Speaker 01 There were probably several hundred million beavers.
6:06 Speaker 04 Making dams and ponds everywhere, even in New York City.
6:10 Speaker 01 There would have been beavers all over New York City.
6:13 Speaker 04 That's right. The Big Apple was once...
6:15 Speaker 01 The Beaver City.
6:19 Speaker 04 And the beavers of Beaver City would wake up every evening, that's right, beavers are mostly nocturnal, in their beaver homes and hit the road, or the stream, I guess, and get to work.
6:29 Speaker 05 Hey, I'm waddling here.
6:30 Speaker 04 Hauling stones and sticks and redirecting water and finishing off each day with a nightcap of sweet wood juice.
6:40 Speaker 01 Manhattan Island was one of the most lush, incredible ecosystems on the eastern seaboard, and beavers were part of what made it that way.
6:48 Speaker 04 But about 400 years ago, all of that would change because of the arrival of Europeans and their insatiable desire for...
6:56 Speaker 01 Hats.
6:57 Speaker 04 Hats?
6:58 Speaker 05 Top hats and cocked hats. Trapper hats with ear flaps, Wellingtons and sugar loaves. That's another name for witch hats.
7:07 Speaker 04 Made of beaver fur. Sorry, guys. They killed them off by the millions for the fur trade. And as the beavers began to be killed off, the land and waterways began to change, pretty dramatically. Like, take the river that slides through the northern part of New York City, winding beside train tracks and beneath highways today. It's called the Bronx River.
7:29 Speaker 06 It was described as an open sewer.
7:31 Speaker 04 That's Christian Murphy. He works on the Bronx River today.
7:34 Speaker 06 It was really just an elongated landfill.
7:37 Speaker 04 And over the centuries, more and more animals disappeared from the river, including the few remaining beavers. And by the 1970s...
7:46 Speaker 06 Parents told their kids, "Don't go down there. It's not safe."
7:49 Speaker 04 Because for decades, companies all along the river used it as a convenient dump for their waste. And people had just given up on the Bronx River. They thought it was just too polluted to care about.
8:02 Speaker 06 In many places, you couldn't see the water because of how thick the trash was.
8:07 Speaker 04 Until one day, someone said...
8:10 Speaker 06 "You know what? This river does not need to look like this. This river could be beautiful. This river could be full of life."
8:15 Speaker 04 Inspired in part by the first Earth Day in 1970, a couple of folks from the neighborhood, like a lady named Ruth and a guy named Fred, they put on gloves and boots and began picking up the trash, bag by bag, day by day. And at first, people kind of laughed. They thought, "What good is a couple of bags of trash gonna do? This whole river's polluted." But then some kids joined in.
8:39 Speaker 05 "Let's do this." "High five."
8:41 Speaker 04 Scooping out trash by the huge garbage bag full. And eventually, someone very powerful joined in too.
8:47 Speaker 00 "Hello, hello."
8:48 Speaker 04 Congressman. His name was Jose Serrano, with a big friendly smile and a bigger bushy mustache. "Let's roll up our sleeves." And start to clean. Who directed millions of dollars to the cleanup project, ordering in trucks with big cranes to fish out refrigerators in cars and helping to change the rules over where factories could dump their toxic waste. And soon.
9:09 Speaker 06 The river began to respond.
9:12 Speaker 04 The water got cleaner and the forest began to regrow around it, bringing in more bugs and birds until
9:22 Speaker 04 a little creature popped its whiskered head out of the water.
9:27 Speaker 06 And it was a beaver.
9:28 Speaker 04 Jose!
9:30 Speaker 01 After an absence of more than 200 years, the beaver has come back to New York City.
9:41 Speaker 04 And so they named him Jose in honor of that congressman who'd been an early bee believer that a little awkward human effort could make a big difference.
9:50 Speaker 05 What an honor!
9:51 Speaker 04 And the fact that Jose the Beaver showed up in the Bronx River wasn't just a sign that the water was getting cleaner, because beavers clean the river too, just by being there and being beavers. See, there's a hidden power to beaver dams. They actually make everything around them healthier.
10:11 Speaker 01 And that happens in a few different ways.
10:14 Speaker 04 So first, there's the water. The dams act like purifiers that filter out pollution like trash and even.
10:21 Speaker 01 Chemicals from agriculture.
10:23 Speaker 04 Which get trapped in the dam and drop down into the soil instead of getting carried out to sea. Second, dams cool the air.
10:34 Speaker 04 Because the pools that dams create mean more water is being evaporated into the air. And so when it's hot, it's kind of like a mini air conditioning unit, making it more hospitable to all kinds of creatures. Third, dams enrich the soil. Nutrients in the water get stuck and drop down into the earth, which creates more fertile ground.
10:58 Speaker 04 And fourth, the real biggie. All of this combined allows new life to sprout. Algies, grasses, cattails and flowers, which attract...
11:08 Speaker 01 Baby trout and salmon.
11:10 Speaker 04 And dragonflies and butterflies and...
11:13 Speaker 01 And frogs and salamanders.
11:15 Speaker 04 And then birds come.
11:17 Speaker 01 Woodpeckers and herons.
11:18 Speaker 04 And pretty soon, coyotes and foxes and in some regions...
11:22 Speaker 01 Moose will come down there to eat all of the aquatic vegetation growing in the ponds.
11:28 Speaker 07 Thank you, Beavs!
11:29 Speaker 04 And in Jose's case, after just a few years of him hanging out in the Bronx River...
11:34 Speaker 06 Somebody looked and squinted their eyes and said, "Wait a minute. There's a second beaver there. There are two beavers."
11:42 Speaker 04 Sacre beave! Another beaver!
11:45 Speaker 06 And so Jose and the second beaver, they were roommates.
11:48 Speaker 04 Classic New Yorkers.
11:49 Speaker 06 Sharing rent on the river, sharing groceries, you know, cutting down the same trees together. And it gets better.
11:56 Speaker 04 I can't imagine it getting any better. But it does. Because you've maybe heard of a little-known pop star named Justin Bieber? Well, they held a naming contest and...
12:07 Speaker 06 And the second beaver was named Justin Beaver.
12:21 Speaker 04 Thank you, Alan. Jose and Justin lived together for years. Munching on wood, swimming with their eyes peeking out of the water, and slowly but surely increasing the biodiversity of the river and the forest around it. And as time has ticked on, the river has only grown healthier, welcoming back snapping turtles and sunfish and even, as was spotted in 2023...
12:44 Speaker 06 Two dolphins swimming around in the Bronx River.
12:49 Speaker 04 No. Yes. Dolphins? Uh huh. Yep.
12:58 Speaker 03 Okay. Go beavers. I can't, I mean, imagine if like, everywhere you walked, you just sprouted flowers and life followed you.
13:09 Speaker 04 That would be nuts.
13:11 Speaker 03 I mean, how long does it actually take? Like, once a dam goes in, is it years before you start seeing this greening effect?
13:17 Speaker 04 No, that's the thing. It's super fast. Like, within a couple of months, there'll be cattails and lily pads and swamp roses blooming.
13:25 Speaker 03 Wow. Okay, so just to recap everything these funky little guys are doing to the world around them. Their dams are cleaning the water, cooling the air, making the soil richer, and increasing biodiversity in these pretty dramatic ways.
13:40 Speaker 04 Yep.
13:42 Speaker 03 But that's it, right? Like, there's no, there can't be anything else.
13:44 Speaker 04 There's so much more.
13:46 Speaker 03 Our next storyteller thinks beavers can even fight fire.
13:53 Speaker 03 Find out how after this break.
14:06 Speaker 02 Pollsters are gearing up to get a bad rap yet again, but they do more than sometimes miss on election outcomes. People want to raise taxes on the rich. I can tell you that definitively because we know it from polling. And if we lose trust in polls, we have no way to understand what Americans want to be done. On this week's On the Media from WNYC.
14:31 Speaker 02 Find On the Media wherever you get your podcasts.
14:39 Speaker 03 Look, up in the sky, it's a bird, it's a plane, no, it's beavers parachuting down from the clouds? Crates full of beavers, part of a shipment to be dropped from an airplane. No, this is not an old-fashioned cartoon. It's something that our governments actually did in the 1940s and 50s. Some folks in a couple of different states put them in boxes and then...
15:02 Speaker 05 And drop those boxes out of airplanes with parachutes on them and let them land in the mountains to do good for us, like move them from the cities to the mountains.
15:09 Speaker 03 You're kidding right now, right?
15:10 Speaker 05 They literally pushed them out of planes. Idaho did this, California did this.
15:15 Speaker 03 This is Dr. Emily Fairfax, and she explains that this was the government's weird idea for pest control. They took beavers that were being nuisances, turning people's yards and farmlands to swamps, and then just dropped them off in the mountains.
15:28 Speaker 05 They are live trapped and moved to distant mountain lakes and streams where their efforts will aid to conserve water, provide fishing pools. Instead of like taking them out on a horseback or a car, they trapped them out of planes, but you know, I give them credit for trying. Now into the air and down they swing, down to the ground near a stream or a lake.
15:49 Speaker 03 Emily gives them credit because she too is trying to bring more beavers out into the wild where they might be able to do some good for the planet. Although that did not used to be her job, far from it. She used to be an engineer who worked on?
16:02 Speaker 05 Weapons.
16:03 Speaker 03 Weapons?
16:04 Speaker 05 Nuclear weapons.
16:05 Speaker 03 Whoa.
16:05 Speaker 05 Very different career path.
16:07 Speaker 03 But she happened to turn on the TV one night and catch a nature documentary.
16:11 Speaker 05 And they were showing all these aerial shots of beaver dams and wetlands in the desert, and they were bright green. And I was like, what? Beavers live in the desert? How can they keep it green when everything's so dry?
16:22 Speaker 03 And she realized that just like her, beavers were engineers.
16:26 Speaker 05 Using all of their engineering to live a good life.
16:29 Speaker 03 And mend the world around them.
16:30 Speaker 05 And I wanted that for myself, so I started studying beavers and I haven't looked back since.
16:35 Speaker 03 Emily hung up her nuclear weapons coat and put on some rubber overalls for a new job, following beavers through wetlands to try to learn how they do what they do. And eventually she came to focus on this one little family of beavers that lived up high in a mountain in northern California in a creek.
16:55 Speaker 05 It's called Little Last Chance Creek.
16:56 Speaker 03 So she called the family the Little Last Chance Beavers. There was a mom, a dad, and?
17:02 Speaker 05 There were definitely three to four babies there.
17:04 Speaker 03 Aww. And she started watching them literally taking notes as they?
17:08 Speaker 05 Timber!
17:09 Speaker 03 Constructed their intricate dams and lodges.
17:12 Speaker 05 We're logging a busy day at work.
17:14 Speaker 03 And she discovered that on really hot, sweaty days inside a beaver's house.
17:20 Speaker 05 It's cold in there.
17:21 Speaker 03 You've been in a beaver lodge?
17:23 Speaker 05 I have.
17:24 Speaker 03 And on super cold days outside? It's super toasty.
17:30 Speaker 05 So the beavers sleep in a big snuggle pile in like one room.
17:33 Speaker 03 Oh.
17:33 Speaker 05 It's very sweet.
17:34 Speaker 03 That's really sweet.
17:34 Speaker 05 They kind of snore sometimes. It's extremely cute.
17:38 Speaker 03 And Emily learned that their family members weren't the only ones staying warm in there.
17:43 Speaker 05 They might have mice that want to come live inside the lodge with them. They might have muskrats that want to live inside the lodge with them. They might have little snakes that want to live inside the lodge with them.
17:51 Speaker 03 Ugh, they allow this? They allow these trespassers?
17:54 Speaker 05 Oh, absolutely. It's kind of like they're running a little bed and breakfast, which I call a bee and beef.
17:59 Speaker 03 Ah, there we go.
18:06 Speaker 03 Winter turned to spring, spring to summer, and then one day, there was a spark. And the dry grasslands and forests around the little last chance beaver family caught fire and began burning and burning.
18:23 Speaker 05 It was a really devastating fire. It burned a lot of forests.
18:25 Speaker 03 This was back in the summer of 2021, and it became one of those mega fires we're seeing more and more of because of climate change. Thousands of people had to be evacuated, hundreds of houses burned down. And as for the plants and critters of the mountains?
18:38 Speaker 05 It seems like absolutely everything has burned.
18:41 Speaker 03 By October, humans were finally able to extinguish the fire, but Emily had no idea what happened to those beavers.
18:49 Speaker 05 Could they have survived the fire?
18:50 Speaker 03 So one day, she began the long drive up the mountain.
18:54 Speaker 05 And the drive up is very disheartening because everything is just blackened and it's silent.
19:04 Speaker 05 Which was the creepiest and strangest part to me.
19:09 Speaker 05 So I'm not feeling like super confident.
19:11 Speaker 03 But she keeps driving.
19:12 Speaker 05 And we find a route in.
19:14 Speaker 03 They get out of the car and begin walking. And suddenly?
19:18 Speaker 05 It is loud. It is splashing water. There's all sorts of birds. There's lots of bugs. There's a lot of wind in the trees and the grasses and the rustling you expect.
19:28 Speaker 03 Oh, wait. And even there being wind in the trees means there's still trees standing?
19:32 Speaker 05 There's still trees. The pine trees that were near it are fine. The trees that are in the wetland are fine.
19:38 Speaker 03 It was completely green.
19:40 Speaker 05 Completely unburnt. Not even just like a little burnt. Like they were unburnt. And When I got there, like honestly, it was like tears in my eyes.
19:50 Speaker 03 Why tears?
19:52 Speaker 05 Because I drove past the burned houses coming up and the burned roads and all the things that we wanted to protect and couldn't. And thinking about the future of climate change and knowing that this is the future that's coming, that's a really difficult reality to wrap your head around. I was living in California at the time. Like, I was seeing my future there. And then getting up to the beaver wetland, it was a very hopeful moment because sometimes it feels like we're all out of ideas and it's not working. But then, right in front of me, something is clearly working. And even if we don't know exactly why or how yet, we can learn from it.
20:35 Speaker 03 And as for the little last chance beavers?
20:37 Speaker 05 I did stay out in the evening and saw both mom and dad swimming. And when they were out swimming, I could hear three, maybe four, different young beaver wines coming from where the lodge was.
20:53 Speaker 03 They made it.
20:54 Speaker 05 Yeah.
20:56 Speaker 03 And it wasn't just them. When Emily looked at the area from way high up in space from a satellite, she saw something incredible. This halo of green around the beavers' dams. She guessed that this one little family, these five or six awkward beings, had saved about seven and a half acres of land from burning.
21:19 Speaker 05 Yeah, that effect is called making fire refugia. It's a patch that doesn't burn that other things can use.
21:25 Speaker 03 Refugia is a fancy word, sort of like for refuge. It's just like place that is safe?
21:29 Speaker 05 Mm-hmm.
21:29 Speaker 03 Okay.
21:30 Speaker 05 Exactly.
21:31 Speaker 03 Refugia.
21:34 Speaker 03 I love this word. I have not stopped thinking about it since Emily taught it to me. How might we all create a little refuge around us for the other beings of this world? Even if we are clumsy and awkward and waddling and tired? I think about the people in the Bronx, those first two or three people who started picking up trash.
21:58 Speaker 05 We got this!
21:59 Speaker 03 And eventually created a ripple effect that cleaned up the river. These things can happen. They do happen in the human world and in the animal world.
22:12 Speaker 03 That day at the beaver dam, Emily saw frogs and birds and even a bear, creatures she suspects might not have survived the fire without that beaver family. And that's why she has come to see beavers as firefighters.
22:26 Speaker 05 Yeah, they're spreading water out across the whole landscape that's keeping everything nice and green and healthy and stopping it from being easy to burn.
22:34 Speaker 03 Emily has tested this effect in mountains and forests and deserts.
22:38 Speaker 05 And so far, what we've seen is that they are really good at making fireproof patches pretty much everywhere.
22:45 Speaker 03 Little rings of green that you can literally see from space.
22:52 Speaker 01 You know, when we talk about restoring nature, we don't always know how to do that. But guess what? Beavers instinctively know what it's supposed to look like.
23:02 Speaker 03 That's Beaver Believer Ben again. He and Emily both work in different ways to inspire and convince people to protect beavers.
23:11 Speaker 01 One of the mantras of the Beaver Believer goes, "Let the rodent do the work. They'll store water for us. They'll capture pollution. They'll help us fight wildfires. They'll create habitat for all of the fish we like to eat and the birds we like to watch and so on. They do all of this stuff for us if we let them.
23:32 Speaker 03 Another mantra: Be more beaver. What if we too worked to build structures that actually mended instead of harmed the land? As pie in the sky, or impossible as that may seem, there are people already out there doing just that, following in the beavers' footsteps, waddling awkwardly toward a better world, one step at a time.
24:35 Speaker 07 Let me see that tail slap.
24:38 Speaker 07 We're small and awkward, and the challenge is tough. If we work together, we can rise above. We waddle on until the job is done. So don't cry as a river. You know we'll just dam it up. I'm a beaver believer. Beaver, beaver.
24:57 Speaker 07 You little overachiever. I'm a beaver believer. Beaver, beaver. Let's get to work. If you believe, roll up your sleeves and... Let me see that tail slap.
25:09 Speaker 07 Even though they're kinda weird, the beaver's got it going on. Those little awkward engineers, sometimes it only takes just one. Maybe two, just a few little critters to chew what needs to be done. And change the world for everyone.
25:37 Speaker 03 Alan Gofinski, Gofinski, everybody. He used real beaver tail slaps as percussion in that. Uh, and that's it. There's nothing else cool about to happen.
25:49 Speaker 03 What's that?
25:49 Speaker 04 Excuse me, I have a question. Me too. Me three. Me four.
25:52 Speaker 03 The Badgers. Listeners with badgering questions for our experts. Are you ready?
25:58 Speaker 05 Absolutely.
26:00 Speaker 07 Hi, my name is Felix, and I'm six years old. Do baby beavers have baby teeth?
26:12 Speaker 03 Yep. Not the big buck teeth, but some of the side teeth, which are called cheek teeth. Cheek teeth, cheek teeth, cheek teeth. Say that 10 times fast.
26:19 Speaker 07 My name is Remy, and I'm six years old. Since beavers eat wood, what does...
26:25 Speaker 03 Does that poop look like?
26:27 Speaker 05 Well, they do the double poop.
26:29 Speaker 03 The double poop? What does that mean? They poop once and then what?
26:35 Speaker 05 They eat that again.
26:36 Speaker 03 Bah.
26:36 Speaker 05 And then when it comes out, it looks like a sawdust marshmallow. And the little sawdust marshmallows, if you dry them out, they're actually great fire starters.
26:42 Speaker 03 What? Have you ever done that?
26:44 Speaker 05 I have burned one to see if it could burn, and it burned just fine.
26:47 Speaker 03 Now, that's what I call a useful nugget.
26:50 Speaker 07 Hi, my name is Tyler. I'm 39 years old. I am trying to figure out how do beavers raised in captivity know how to build a dam, even if they've never seen a river?
27:04 Speaker 05 They learn from their instincts and also from following around their parents and brothers and sisters and trying to do what they do.
27:10 Speaker 03 Wait, so are there regional differences in architectural style? Like how you get Swedish modernism or southwestern adobe?
27:19 Speaker 05 Anecdotally, yeah, there are. And some of them built some really weird dams.
27:23 Speaker 03 Really? Like, how so?
27:25 Speaker 05 Like, at like 90-degree angles from one another, like zigzagging instead of having nice curvy shapes.
27:30 Speaker 03 Huh.
27:31 Speaker 05 They like teach their kids what's available to build with. It could be garbage, mud. I have seen cow bones. I have seen all sorts of interesting things.
27:39 Speaker 03 Oh, spooky, a dam made out of bones? Like a skeleton dam?
27:43 Speaker 05 No joke, I saw that on a Halloween field tour, and I thought someone had like set it up for me.
27:47 Speaker 03 Haunted lodge, haunted dam.
27:49 Speaker 05 Just like cow knuckle bones and a femur, and they're just like integrated into this dam. It was like unreal.
27:56 Speaker 03 And that's where we gotta leave it with the Spawuuki Beaver Dam. And I won't tell you that vanilla ice cream, candy, yogurt, and many perfumes used to be made with an oil that came from the beaver's booty. It was called castorium. And that's true, if you used to eat like vanilla ice cream or certain candies back in the time of like your great-great-grandparents, you were actually tasting beaver bum. I won't tell you that because I'm nice, but I did learn it in Beaver Believer, Ben Goldfarb's great book called Eager: The Surprising Secret Life of Beavers and Why They Matter. Highly recommend you check it out. And that'll do it for today. Terrestial's with- Created by me, Lulu Miller, with WNYC Studios. Our executive producer is Sarah Samback.
28:40 Speaker 03 This episode was produced by the naughty gnawing-on-wood Anna Gonzalez. Tail-slappingly-good sound design by Mira Burtwin-Tonic. Our team also includes Alan Gofinski, Talia Chala, and Joe Plord. Fact-checking by Diane Kelly. She would not let us get anything wrong. "Wood" spelled W-O-O-D. Support for Terrestrials is provided by the Simons Foundation, the Arthur Reining-Davis Foundations, and the John Templeton Foundation. Thank you. We have got new episodes churning out every two weeks. We hope you'll listen and subscribe to the Radiolab for Kids feed, and tell your friends. It really helps our chances of getting to keep going. We also have social media, where Alan drops Frog Fact Friday videos every Friday. Frog Fact Friday.
29:26 Speaker 03 And we also have animated music videos contests, and just like me saying hello in various natural places, that's @terrestrialspodcast. And if you want to submit a badger's question, sign up for our newsletter or check out past episodes, just head on over to www.terrestrialspodcast.org. Okay, hopefully all those links would work for you. Would work? Would work? Nah. Okay, be very careful out there. Go sink your teeth into some good stuff. And see you in a couple spins of this dirty, old planet of ours. Woo, woo, woo, woo, woo. Bye.
30:06 Speaker 04 Hi, I'm Maddy, and I'm from Frederick, Maryland. Leadership support for Radiolab's science programming is provided by the Simmons Foundation and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.
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