While Curiosity Daily is a on a break for the holidays, we wanted to leave you with a few of our favorite episodes from 2022. Today, you’ll learn about how COVID-19 may have revamped cities for the better, astounding new technology that could one day regrow human limbs and how an agricultural fertilizer is going from feeding the world to potentially powering the world.
Today, you’ll learn about how COVID-19 may have revamped cities for the better, astounding new technology that could one day regrow human limbs and how an agricultural fertilizer is going from feeding the world to potentially powering the world.
Covid’s Bright Side
Frogs Out On a Limb
Fertilizing Fuel
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/re-release-covids-bright-side-frogs-out-on-a-limb-fertilizing-fuel
CALLI: Hi guys! Welcome back to Curiosity Daily, I’m Calli. Before we get into today’s episode, I wanted to let you know that during the holiday season we’ve been re-releasing some of our favorite episodes from this past year. So, if you haven’t already checked those out, you should! Today’s show is one of our most popular and my favorite story is one where we talk about some very hoppy frogs. This is the last of our re-releases so, on behalf of everyone here at Curiosity Daily, we wish you a happy holidays and a happy new year. See you in 2023!
[SFX: INTRO MUSIC/WHOOSH]
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today, you’ll learn about how COVID-19 may have revamped cities for the better, astounding new technology that could one day regrow human limbs and how an agricultural fertilizer is going from feeding the world to potentially powering the world.
CALLI: Without further adieu, let’s satisfy some curiosity!
[WHOOSH]
CALLI: Hey there. Before we get into our story, let’s first recognize that, as of March 2022, over six million people have lost their lives to COVID-19. Six million. That’s a hard number to imagine, but it includes grandparents, mothers, fathers, siblings, daughters, sons and friends.
NATE: That’s right… We all have been affected by the pandemic… some more than others… without a doubt. Our species will be emerging from this mess for years to come.
CALLI: So, now, more than ever, we’re lookin’ for a silver lining. A bit of hope to grasp onto as we finally step into the cliché “new normal” that everyone has been talking about.
NATE: Ugh… New normal… If I had a nickel for everytime I heard that phrase.
CALLI: You’d have a lotta nickels. But then ya gotta put ‘em all in like a bunch of Ziploc bags, lug them to the bank and get ‘em counted. The phrase should be “If I had a hundred dollar bill for every time I heard that phrase.”
NATE: That’s actually a really good point… We’re short-changing ourselves… That phrase probably originated decades ago when a nickel could buy you a house.
CALLI: Exactly. And that is a perfect transition to today’s story. America’s major cities really haven’t changed that much since the 1800s. They're a reflection of urban planning from decades ago. People flocked to cities for jobs during the manufacturing boom of the Industrial Revolution. Places like New York, Boston, Chicago and Los Angeles exploded. So did their populations. Then, in 1908, Henry Ford’s assembly line brought the famous Model T automobile to the market. Now, people didn't need a horse and buggy. It made life, and work, a lot easier. But not everyone could afford one.
NATE: Could you imagine. One day… you’re at home feeding your horse… let’s call him Frank… and then you hear (SFX: old timey car horn). It scares the crap outta Frank… So you turn around to see your annoying… one-upper neighbor in his new Model T. You’re like… what is that? And he’s like… it’s a car, you peasant… And then he drives away. Slowly. Because cars didn’t go fast back then… Oh man. Poor Frank.
CALLI: You okay, Nate?
NATE: Yeah… I just have a really annoying neighbor… Anyway, what were you saying?
CALLI: So cars started to be mass produced. Along with trucks and buses. Suddenly, you didn’t need to live next door to the factory you worked in. As populations grew and grew, the design of cities was heavily influenced by transportation. I mean, think about it. If you ask anyone where something is in a city, they give you street names and intersections. They could easily tell you in distance and direction, but street names are easier. This worked really well for a long time, until we realized that fossil fuel-burning transportation accounts for almost a third of carbon emissions in the United States. Which is horrible for the environment. The very things that allowed cities to thrive were now choking them. And then something else happened.
NATE: Lemme guess… That something else is COVID-19.
CALLI: Ding ding ding ding ding ding! You’ve won the grand prize of… a new understanding of urban planning. COVID rapidly disrupted just about everything in city life. The pandemic, and response to it, forced people to change their perception of cities. Suddenly, we had to envision something different. Public health experts informed us that being outdoors was safer. So, restaurants, shop owners and city planners scrambled to convert parking lots and parking spaces to retail locations. Whole streets were closed for pedestrians. Some still are today. Events that normally took place indoors went outdoors. Mini parks, where people could safely socialize, began popping up, reliance on personal cars dropped and green was the new black.
NATE: So COVID actually reconnected us with the environment.
CALLI: In a way. Yeah. We don’t know if these changes were driven for business reasons or by a real desire to revamp cities. Probably a mix of both. But they happened. Is this gonna save the world? I don’t know. But it’s a start. What we need to understand is that humans struggle to imagine things we’ve never seen. And everyone alive today only knows cities built around cars. But now, we’ve seen something different. And with people working remotely and rental prices going through the roof, I think it’s just a matter of time before cities also face their version of a new normal.
NATE: Seems like the big question is… will it stay this way?
CALLI: Only time will tell. But out of a pandemic that is still making so many people sick, we’re seeing a healthier possibility of what cities could be. And that is our silver lining.
[WHOOSH]
NATE: Let’s play some word association, Calli. Tell me the first things that come to mind when I say the following word… Frog.
CALLI: Ribbit. Lillypad. Tree. Toad. Amphibian.
NATE: Interesting… Is that it?
CALLI: Nope. Tadpole. And Kermit. That’s it.
NATE: I see that you left out… pioneer of groundbreaking medicine.
CALLI: Because that’s new information to me. Do I sense a story, Nate?
NATE: Yes you do… Let’s hop to it.
CALL: I know you listeners can’t see me, but I’m rolling my eyes. Hard.
NATE: Frogs and humans have always had an interesting relationship….. From fairy tales to fine art, they pop up a ton throughout history… The ancient Egyptians, Greeks and Romans viewed frogs as symbols of fertility and harmony… While traditional Chinese culture associates them with healing… And the Chinese got it right because frogs have been super important to modern medicine. In the past 60 years, a bunch of people won Nobel prizes for experiments involving frogs… And even though these cold-blooded creatures don’t seem to have a lot in common with humans… they deserve a ton of credit for their contributions to our species… If you still don’t believe me, wait till I tell ya what researchers at Tufts University were able to achieve… Lemme introduce you to Xenopus (PRONUNCIATION).
CALLI: Oh, that’s a fun word! It sounds like the start of a spell in Harry Potter. (as if you’re delivering the incantation) Xenopus Wingardium Leviosa!
NATE: Now I’m rolling my eyes. If we’re going to Hogwarts with it… you’re gonna wanna use the incantation Ferula (feh-ROO-luh)… It’s a charm that conjures bandages to heal broken bones… This will make sense shortly.
CALLI: Okay okay. But really, who, or what, is Xenopus?
NATE: Xenopus is the biological category that includes African clawed frogs. These amphibians are the unsung heroes of biological science… and they were involved in a very cool achievement from those researchers at Tufts University.
A team of biologists… led by Michael Levin… surgically amputated the back, right leg of 115 African clawed frogs. Now this sounds like a scene from a horror movie… but hear me out. The amputated frogs were separated into three categories. Let’s call them HOP, SKIP and JUMP. HOP had a silicone sleeve, called BioDome, placed over their wound. SKIP also had the BioDome sleeve, but they got an added bonus of a protein gel mixed with a growth hormone… a nerve growth promoter… and an anti-inflammatory drug. And poor JUMP got nothin because they are the control group. (SFX: clock tick tick tick increasing in volume) After twenty four hours…
CALLI: (SFX: a few more tick ticks then a bell Dings) DING!
NATE The researchers removed the BioDome sleeves from the frogs that got it. Then back into the tank every Xenopus went. The frogs were closely monitored and tested… and that went on for eighteen months. Now you won’t believe what happened next. Calli, do you remember our test frog categories?
CALLI: Yup! HOP had the BioDome and nothing else.
NATE: Right. They saw some regeneration in the amputated limb. It started to grow back… but didn’t quite make it all the way. The researchers think the growth that did happen was created by the stiffness and pressure from the silicone sleeve. And it doesn’t end there… because this story goes from cool to holy freaking crap. Next group?
CALLI: SKIP! They had BioDome plus that special drug cocktail.
NATE: Yes! They almost entirely grew their legs back and had toes in the right place! Oh… and this is a mind blower…the new legs were longer and made of stronger bones. They were also packed with more blood vessels and nerves. Using their new, bionic legs, they were able to stand and push off the walls of their tanks! It was like the researchers had cast a biological spell…. or… Xenopus Ferula (feh-ROO-luh).
CALLI: I got it. You don’t have to rub it in. But what happened to the froggies in the JUMP category?
NATE: They couldn’t jump. They grew stumpy, spikey flaps that served no function. Now before that bums you out… you need to realize that this is what would normally happen. But the brilliant researchers at Tufts were undeterred! Their BioDome technology activated new limb growth that lasted for several months.
This is a massive step forward in the world of regenerative medicine. While human beings and Xenopus are very different… this research shows that… one day… this comic book super power could leap into the real world. We humans may also be able to regrow limbs. And for the millions of people who have lost arms or legs to disease or trauma… this gives a ton of hope.
CALLI: Now this is what I call a hoppy ending.
NATE: Oh… so you’re the only one who can make cringey puns?
[WHOOSH]
CALLI: Whether you live in the Midwest or just drive through during a road trip, you can’t help but feel a deep sense of pride and amazement when you see the scale of the American agricultural industry. (SFX: Patriotic music) Among the rolling plains of corn, soybeans and wheat, our brothers and sisters work their land, day and night, to feed hundreds of millions of people.
NATE: That sounds very patriotic, Calli… Are you running for Congress?
CALLI: No! I just think it’s amazing what we can produce.
NATE: You’re right… Honestly, in our tech-driven, hustle culture… America’s farmers don’t get enough love... They’re the world’s unsung heroes... So we, at Curiosity Daily, salute you… Thank you for the wheat… which gives us flour… to make my favorite pasta.
CALLI: But along with any industry that’s been around for centuries, there is room for improvement. So this story begins with big changes in the world of fertilizer.
NATE: Oh… That was a very long set up to say that this story is about poop.
CALLI: It’s actually not. And that’s one of the biggest misconceptions about agriculture. That’s not where all fertilizer comes from. So, you, along with our listeners, are about to learn something new, Nate. This story is about ammonia. Now, ammonia is a colorless, pungent gas that is made up of nitrogen and hydrogen. It is used a lot to make agricultural fertilizers. And the classic way of making ammonia is using a method called the Haber-Bosch process. It’s named after the chemists who invented it in the early 1900s. They eventually won a Nobel Prize for it. Anyway, it involves using steam to remove hydrogen from natural gas. Then this hydrogen is combined with nitrogen at crazy high pressure and temperatures.
NATE: Steam… Natural gas… Sounds fine to me… What’s the problem?
CALL: Well, this process releases about two tons of carbon dioxide for every one ton of ammonia that is made. This goes straight into the atmosphere. And we all know that ain’t good. Because agriculture is a global industry, the world currently creates about one hundred seventy five tons of ammonia per year. That’s three hundred tons of greenhouse gasses. So “dirty” ammonia makes up about one to two percent of global carbon emissions. That doesn’t sound like a lot, but it makes fertilizer production one of the dirtiest industries on the planet.
NATE: Well, I coulda told ya that.
CALLI: Nate. Can ya stop thinkin’ about poop? We’ve moved off poop.
NATE: Fine… So, what are we doing to clean up “dirty” ammonia?
CALLI: First of all, they need to use cleaner energy. And not natural gas. They can do this by pulling hydrogen from water using electricity from renewable sources. From there, that Haber-Bosch process we talked about earlier is the same. Just now powered with cleaner energy. Let me explain by example! In the land of ten thousand lakes, there’s a research farm run by the University of Minnesota with a bunch of wind turbines. The wind provides power to a chemical plant creating “green” ammonia that can be spread as fertilizer. And, even more groundbreaking, this ammonia can be used as fuel and heat. The university’s studies show that all of this could reduce agriculture’s carbon footprint by ninety percent. Nine zero. That is game changing.
NATE: Wow… And if it can be used for fuel and heat… it must have other applications, right?
CALLI: Totally. Green ammonia can be used as fuel in the shipping industry, which also has a major carbon footprint. About three percent of global emissions come from shipping. In addition, green ammonia can be burned in power plants to create energy worldwide. The beautiful thing about this very powerful green goddess is that she is easy to store as a liquid and has about half the density of normal fossil fuels. And the world already has a huge system in place for ammonia production, storage and transportation.
NATE: So green ammonia could genuinely help us get to net zero carbon emissions?
CALLI: Yup. It certainly can’t solve every fuel-related problem, but if you pair it with biofuels and hydrogen, we’re looking at a much cleaner future. There are experimental plants currently producing green ammonia in Britain and Japan. And with the United States, Australia and Saudi Arabia set to begin massive green ammonia producing projects in the next few years, that future might be here sooner than we think. And it could change everything. One expert believes green ammonia could likely be the liquid fuel of the future.
NATE: From farms and fertilizer… to the future of fuel, it’s the everyday citizen who is going to save the future. Because if we can’t rely on one another, who can we rely on?! So I’d like to formally announce I’ll be joining Calli on the campaign trail.
CALLI: I told you, I’m not running for office.
NATE: We are currently accepting donations.
[WHOOSH]
NATE: Let’s recap what we learned today to wrap up. Starting with…The COVID-19 pandemic. It shook up the entire world, but it gave us a different, healthier perspective of what cities could be. Reconnecting us with the environment, there may be a world where vehicles aren’t the first thing city planners consider.
CALLI: Researchers at Tufts University proved that limb regeneration is possible in African clawed frogs. While human applications are still a ways away, this gives tons of hope to people who have lost limbs from disease or trauma.
NATE: The agriculture industry has relied on ammonia to help feed the world. But today, a cleaner process that produces green ammonia could revolutionize the way human beings power the world.