The Builders

If Earth Day is coming up on April 22nd, so this week I wanted to bring you a story that is just a whole-hearted celebration of nature for Medialab's spin-off to restriles. We released it last fall in the Radio Lab for Kids Feet, but look, I am a card carrying

“grown-up, 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. Hey, wait, you're listening. Three, two, one. Imagine. You wake up in the dark. Your eyes dart around to see a little circle of blue shimmering light. You water over on your webbed feet and realize it's water. So you dive in head first. As you kick and glide, you grow fur. Really thick fur, and

an extra set of eyelids. The act like goggles under water, and then you look behind you to find a big black-skilly paddle. It's your tail, which you can slap on the water with a nice, loud, who have become a beaver.

“Okay, now is the part where I make you sing the theme song with me.”

Okay, I'm ready. We are not the worst. We are the first. Try again. Opposite of worst is the best. Best dream. Yeah, you got it. Okay, I like it. Dressedreels is a show where we uncovered the stranginess, waiting right here on Earth.

I am your host, Lulu Miller, joined as always by my soundbud.

Take me to the river. Allen swimming with the beaver. So here we are kicking off this brand new season of terrestrials. While all around us really hard things are going on, wild fires, 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, then beavers. Yeah, those buck-toothed, whaddling, 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 see it from space. 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 produced about Anna. Yep, does me? Yeah, Jose is this incredible

symbol. And here to help me is Ben Goldfibh, who's a writer. And beaver believer. Does that be believing? So Jose, he waddles out into the world with little webbed feet and whiskers and very large buck-toothed that are bright orange, because apparently beavers teeth actually contain iron. Whoa, metal teeth. Yeah, like chisel, shound. The iron makes their teeth excellent for chopping down trees. Because beavers have one single obsessive

pottery. It's not drying or knitting or doing puzzles. The classic beaver behavior that most people know about is they build dams. A dam is basically a wall in the water that beavers build by dragging the trees that they chomp down across the flowing stream, blocking the water. Instead of adding mud or other stuff to keep that wall sealed up tight. When you see them sometimes carrying rocks around in their little frug paws, whaddling on

their hind legs, it's like the cutest thing ever. A beaver dam makes water accumulate behind the barricade, turning a trickling stream into a new pond in the middle of the forest.

Ah, time for a shrimp. On a kid's interrupt to ask why? 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. That's a great question. I mean, the 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 going to

on land with their webbed feet and huge tail that drags on the ground. Beavers are not

“good at running, making them easy pigments for land predators. So if you're a beaver, you”

want to spend as little time on land as possible. So by making dams, they create deep pools of water, which allows them to transform from wobbly wolf snacks to elegant professional swimmers. We can spin and twirl and hold their breath for up to 15 minutes. Yeah, they're

like a magical animal, yeah, they're just incredible. Pretty epic hiding place. Now hundreds

of years ago, in the time of Jose is great, great, great, great, great, great, great grandparents, the woods of North America was full of beavers. They were probably several hundred million beavers. Making dams and ponds everywhere, even in New York City. There would have been beavers all over New York City. That's right, the big apple was once. The beavers city. And the beavers of beavers city would wake up every evening. That's right, beavers are mostly

“not tangled in their beaver homes and hit the road. Or the stream, I guess, and get to work.”

Hey, I'm Waterland here. All in stones and sticks and redirecting water and finishing off each day with a nightcap of sweet wood juice.

Manhattan Island was one of the most lush incredible ecosystems and the eastern seaboard

and beavers were part of what made it that way. But about 400 years ago, all of that would change because of the arrival of Europeans and their insatiable desire for hats, hats, top hats and top hats, trepper hats with ear flaps, Wellington and Sugar Loafs. That's another name for which hats. 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.”

It was described as an open sewer. That's Christian Murphy. He works on the Bronx River today. It was really just an elongated landfill. And over the centuries, more and more animals disappeared from the river, including the few remaining beavers. And by the 1970s, parents told their kids, "Don't go down there, that's not safe." 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 it. In many places, you couldn't see the water because of how thick the trash was. Until one day, someone said, "You know what? This river does not need to look like this. This river could be beautiful. This river could be full of life." 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, "Well, good is a couple of bags of trash going to do. This whole river is polluted." But then, some kids joined in. "Let's do this." I find. Scooping out trash by the huge garbage bag full.

And eventually someone very powerful joined in too. "Come on, come on."

Congressman. His name was Jose Serrano. With a big friendly smile and a bigger bushy mustache. "Let's roll up our sleeves and start a clean." Who directed millions of dollars to the Cleanup Project, ordering in trucks with big cranes to fish out refrigerators and cars and helping to change the rules over where factories could dump their toxic waste. And soon, the river began to respond. The water got cleaner.

And the forest began to regrow around it, bringing in more bugs and birds. Until, well, a little creature hopped its whiskered head out of the water. And it was a beaver. Jose! After an absence of more than 200 years, the beaver has come back to New York City. Until they named him Jose in honor of that congressman, who'd been an early beaver

that a little awkward human effort could make a big difference. "What an honor!" 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.

So first, there's the water. The dams act like purifiers that filter out pollution, like trash

“and even chemicals from agriculture, which get trapped in the dam and drop down into the soil instead”

of getting carried out to sea. Second, dams cool the air. 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. And fourth, the real biggie. All of this combined allows

new life to sprout. Allgy's grasses, cattails and flowers, which attract baby trout and salmon, and dragonflies and butterflies. Frogs and salamanders. And then birds come. Woodpeckers and herons.

“And pretty soon, coyotes and foxes and then some regions. Moose will come down there to eat all of the”

aquatic vegetation growing in the ponds. And in Jose's case, after just a few years, of him hanging out in the Bronx river. Somebody looked and squinted their eyes and said,

"Wait a minute. There's a second beaver there. There are two beavers."

Another beaver. And so, Jose and the second beaver, they were roommates. Closy New Yorkers. Sharing rent on the river. Sharing groceries. You know, cutting down the same trees together. And it gets better. I can't imagine I can't get 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 the second beaver was named Justin Bieber.

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 in 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, two dolphins, swimming around in the Bronx river. No, yes, dolphins. Yep. Okay. Go beavers. I can imagine if like everywhere you walked, you just sprouted flowers. Life followed you. That would be nuts. I mean, how long does it actually

take? Like, once a dam goes in, is it years before you start seeing this greening? No, that's the thing. It's super fast. Like, within a couple of months, there'll be cat tails and lily pads and swamp roses blooming. 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. But that's it, right? Like,

there's no, there can't be anything else. There's so much more. Our next storyteller thinks beavers can even fight fire. Find out how. Have a nice break. This episode is sponsored by BetterHelp. Guys, it's tax season. Are you a stoked as I am? No, no, of course you aren't, because taxes can be super stressful. I know that I'm going to owe money, and so I'm avoiding all the emails from my accountant. I'm not alone. 88% of Americans

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betterhelp.com/radialab. Hungry's newly elected prime minister praise the independent media outlet

when public media was propaganda. Peter Maggare vows to free up the media and will likely succeed,

“because the bar is so low. You're being compared to Victor Urban. You can only be great for the press.”

On the next on the media from WNYC. Find on the media wherever you get your podcasts. Look, up in the sky. It's a boom. It's a plane. No. It's beaver's parachuting down from the clouds. Greats full of beaver. Part of a shipment to be dropped from an airplane. No. This is not an old fashion cartoon. It's something that our government actually did in the 1940s and 50s. Some folks in a couple of different states put them in boxes and then drop those boxes

out of airplanes with parachutes on them and let them land in the mountains to do good for us.

Like, moving from the cities to the mountains, you're kidding right now, right? They literally

pushed them out of planes. Idaho did this. California did this. 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. 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 car, they trap from out of planes, but you know, I give them credit for trying. No, into the air and down my swing, down to the ground, near a stream or early. 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 weapons, weapons, nuclear weapons, well, very different group path, but she happened to turn on the TV one night and catch a nature documentary. 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? And she realized that just like her, beavers were engineers. Using all of their engineering to live a good life and men the world around them. And I wanted that for myself. So I started staying beavers and I haven't looked back since. Emily hung up her nuclear weapons coat and put on some rubber overalls for a new job following beavers through wetlands to try and 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. It's called Little Last Chance Creek. So she called the family, the Little Last Chance beavers. There was a mom, a dad, and there were definitely three to four babies there. And she started watching them literally taking notes as they constructed their intricate dams and lodges. We're logging a busy day at work. And she discovered that on really hot, sweaty days

inside a beavers house. It's cold in there. You've been in a beavers? I have. And on super cold days outside. It's super tasty. So the beavers sleep in a big snuggle pile in like one room. It's very sweet. That's really kind of snore sometimes. It's extremely cute. And Emily learned that their family members weren't the only one staying warm in there. 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. They allow this. They allow these trespassers? Oh, absolutely. It's kind of like they're running a little bed in breakfast, which I call a be in beavers room. My horrible jokes. 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, began burning and burning. It was a really devastating fire. It burned a lot of forests. 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, it seems like absolutely everything

has burned. By October, humans were finally able to extinguish the fire, but Emily had no idea what

happened to those beavers. Could they have survived the fire? So one day, she began the long drive up the mountain. And the drive up is very disheartening because everything is just blackened and it's silent, which was the creepiest and strangest part to me. So I'm not feeling like super confident, but she keeps driving. And we find a route in. They get out of the car and begin walking.

There's a lot of wind in the trees and the grasses and the rustling you expect. Oh wait. And even there being wind in the trees means there's still trees standing. There's still trees. The pine trees that were near it are fine. The trees that are in the wetland are fine. It was completely green. Completely unburnt. Not even just like a little bird. Like they were

“unburnt. And when I got there, like honestly it was like tears in my eyes.”

Why tears? 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. And as for the little last chance beavers,

“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 beavers' wines coming from where the lodge was. They made it. Yeah. 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. Yeah, that effect is called making fire refugia. It's a patch that doesn't burn to other things can use. Refugia is a fancy word for refuge. It's just like place that is safe. Mm-hmm. Okay. Exactly. Refugia. 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 waterling and tired. I think about the people in the

Bronx. Those first two or three people who started picking up trash. We got this.

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. 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.”

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. Emily has tested this effect in mountains and forests and deserts. And so far what we've seen is that they are really good at making fire proof patches. Pretty much everywhere. Little rings of green. You can literally see from space.

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. That's beaver believer Ben again. He and Emily both work in different ways to inspire and convince people to protect beavers. One of the monstrous of the beaver believer goes, let the road and 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. 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 foot steps, watering awkwardly toward a better world, one step at a time.

come. If we work together, we get rise up up, we want all on until the job is done. Don't cry as a river.

We know we'll just dam it up. The beavers got it going on. Those that are awkward engineers sometimes it only takes just one. Maybe two does a few little critters. A chew what needs to be done and change the world for every one. Ellen Gopher and Skye. He used real beaver tail slaps as percussion in that and that's it.

There's not enough school about to have a go.

What's up? Excuse me. I have a question.

“Me too. Me too. Me too. A batcher. Listeners with Badger and questions for our experts. Are you ready?”

Absolutely. Hi. My name is Felix and I'm six years old. You baby beavers have baby teeth. Yep. Not the big buck teeth, but some of the side teeth, which are called chick teeth, chick teeth, chick teeth say that ten times less. My name is Remy and I'm six years old. Six beavers eat wood. What does that poop look like? Well, they do the double poop. The double poop. What does that mean?

They poop once and then what? They eat that again. And then when it comes out, it looks like a sawdust marshmallow. And those sawdust marshmallows, if you dry them out, they're actually great fire starters. What? Have you ever done that? I have burned one to see if it could burn and it

“burned just fine. Now that's what I call a useful nugget. Hi, my name is Tyler. I'm a 39 years old.”

I am trying to figure out how do beavers raise in captivity know how to build a down.

Even if they've never seen a rubber. They learn from their instincts and also from following

around their parents and brothers and sisters and trying to do what they do. Wait, so are there regional differences in our contextual style? Like how you get Swedish modernism or self-lastered Adobe. And it totally, yeah, are. And some of them build some really weird dams. Really? Like how so? Like at like 90 degree angles from one another, like zigzagging instead of having nice curvy shapes. Huh, 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. Boogie, a dam made out of bones. Like a skeleton. A dam? No joke. I saw that on a Halloween field floor. And I thought someone had like set it up for me. Haunted, large. Yeah. It's like cow knuckle bones and a femur. And they're just like integrated into this dam. Like unreal. And that's where we got to leave it with the Spowoo. Ki-biver dam. Ha ha ha. 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

“believe her. Ben Goldfarb's great book called Eager, the surprising secret life of Beaver's”

and why they matter. Highly recommend. You check it out. And that'll do it for today. Terrestrial is was created by me. Boogie Miller with WNYC Studios, our executive producer is Sarah Sambac. This episode was produced by the naughty, annoying on wood on a gazales. Tales slapping we good sound design by Merber. Wintonic, our team also includes Alan Gophinski, Tanya, Tala, and Joe Plord, fact-checking by Diane Kelly. She would not let us get anything wrong. Wood spelled

W-O-O-D. Support for Tales is provided by the Simon's Foundation, the Art of Riding Davis Foundations, and the John Tableton Foundation. Thank you. We have got new episodes turning out every two weeks. We hope you'll listen and subscribe to the radio app for kids feed. And tell your friends. It really helps our chances of getting to keep going. We also have a social media where

videos, contests, and just like me saying hello in various natural places. That's at terrestrial's

“podcast. And if you want to submit a badgers 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. Okay, be very careful out there. Go sink your teeth into

“some good stuff and see you in a couple of spins of this dirty old planet of ours.”

Hi, I'm Maddie and I'm from Frogger, Maryland. Leadership support for radio lab science programming

is provided by the Simmons Foundation and the John Templeton Foundation. Foundation also support

“for radio lab was provided by the Alfred Peace Loan Foundation.”

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