Today, you’ll learn about why symmetry dominates the natural world, how it may be possible to conserve water using solar panels, and why growing vegetables might soon involve a trip to the Moon.
Today, you’ll learn about why symmetry dominates the natural world, how it may be possible to conserve water using solar panels, and why growing vegetables might soon involve a trip to the Moon.
Two halves make a whole.
Sun = more water.
Grocery shopping on the moon.
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/why-symmetry-wins-solar-covered-canals-plants-on-the-moon
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 why symmetry dominates the natural world, how it may be possible to conserve water using solar panels, and why growing vegetables might soon involve a trip to the Moon.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: Intro Music/Whoosh]
NATE: Calli, have you ever noticed how often symmetry can be found in the world around us?
CALLI: Like how a person’s right and left legs are basically the same, just mirroring each other.
NATE: Yeah, totally. Biological symmetry is everywhere. From the radial symmetry of a flower, to the bilateral symmetry of a butterfly's wing designs.
CALLI: Right, of course. I’m more/less symmetrical myself, despite my side part.
NATE: Exactly yeah. Well, symmetry is even found in the structures of our biological building blocks like proteins and RNA - which is basically a cousin of DNA.
CALLI: So symmetry is all around us in the natural order of things - but why? I can’t think of any obvious inherit benefit. So, it doesn’t seem like it would be beneficial enough for it to be part of natural selection...
NATE: A new study published in Proceedings of the National Academy of Sciences highlighted a team of researchers who set out to answer that very same question. They analyzed thousands of protein complexes, RNA structures, and a network of molecules that control how genes switch on and off. Hoping to find out why these building blocks heavily favor symmetry when they go to work.
CALLI: Oh man. What did they find?
NATE: To be honest, it seemed quite obvious after the fact.
CALLI: Can I guess?
NATE: Sure yeah.
CALLI: You mentioned building blocks, so I would think that it might be easier to copy patterns rather than constantly making up new ones... Kinda the way Shakespeare used iambic pentameter, which made the lines easier to memorize.
NATE: That’s exactly right! The study revealed that biology leans towards symmetry because these symmetrical patterns are simply ... simpler. If the patterns are simpler, the work to build the organism is easier. The researchers studied this principle in both how proteins assemble and how RNA folds for ten years. And they continuously found that simpler shapes appeared more often.
CALLI: Work smarter, not harder.
NATE: Yep! And interestingly, the first discoveries on this came from the computer science world. Specifically, testing simulations to understand how viruses form their protein shells, which are the part of the virus that holds its genetic material. I’m sure you’ve seen images of viruses that look kinda like a little space ship.
CALLI: Yeah, of course. Little legs at the bottom, and a sort of place where the astronauts might be at the top?
NATE: Yeah! That’s the protein shell, also known as a capsid.
CALLI: Got it, got it. I’m assuming these simulations showed a big preference for symmetry in the results?
NATE: Bingo. One of the scientists from the study compared it to giving instructions to someone for tiling a floor - It would be much easier for them to put down tiles in simple and identical rows than it would be for them to create complex patterns all across the floor.
CALLI: Geez, this sounds like a pretty big discovery.
NATE: It’s essentially a new law of nature. It could fundamentally change the way we see the biological world. Including the way we look at human biology! I mean, just imagine the possibilities.
CALLI: Cool, so like a really gigantic humongous deal.
NATE: Gigantic humongous sums it up, yeah. And even though the studies were really only conducted on the microscopic level, it’s believed that these repeating patterns scale all the way up to much larger and more complex organisms.
CALLI: I mean the proof seems pretty evident with the symmetry of large animals, humans, flowers ... I mean, you name it.
NATE: Yes, totally. It’s of course important to mention that there is plenty of biological asymmetry, and that typically comes from certain twisting proteins, or simply the natural selection process of evolution.
CALLI: Natural selection, right. So, sometimes asymmetry just wins out. But, typically, symmetry does?
NATE: Yeah, that was another key facet of this study - the relationship between the simplicity of symmetry and the evolutionary process. Because symmetry makes for much simpler instruction sets in nature’s biological processes - evolution ends up heavily favoring these symmetrical sets when it comes to picking and choosing for natural selection.
CALLI: Right, so at this point in history, there are way more symmetrical options to choose from, when picking the building blocks of a given organism.
NATE: You got it!
CALLI: Keep It Simple and Symmetrical.
NATE: Now even with all this research we’re still a long way away from completely deciphering the links between microscopic symmetry and super large-scale symmetry. Even if we’re seeing symmetry in larger organisms, like you mentioned animals, plants, humans, et cetera - we still don’t have enough data to fully explain all the connections at play between the micro and macro.
CALLI: I look forward to the update when it comes.
[SFX: Whoosh]
CALLI: Nate, I wanna talk about one of the most valuable resources on Earth.
NATE: Diamonds? Gold?
CALLI: Not that kind of valuable. I’m talking about water.
NATE: Ah, I get you. What’s new with water?
CALLI: Well, we all know the western United States have faced historically extreme droughts in the past year. Even states like Oregon, Colorado, and Washington - all renowned for their plentiful water supplies, have been ravaged by severe dehydration climates and resulting wildfires.
NATE: It’s definitely distressing. I’ve seen plenty of fires near where I live in Utah. It’s awful during wildfire season.
CALLI: Yeah, there’s never been a more necessary time to address growing water supply issues. Evidence suggests that the western U.S. is in the worst megadrought of the last twelve-hundred years and some believe it may extend even past this year. Leaving roughly sixty million people at constant risk of wildfire evacuation, or, of running dangerously low on their water supplies.
CALLI: And it may not be long until those droughts start hitting the middle of the country and eastern parts as well.
NATE: Right. It’s getting very serious. Now, one of the states you hear about most with droughts is California - there are a ton of people there, using water every day like other states, but also California provides crops for states all over the country, including over a third of America’s vegetables and over two-thirds of our fruits and nuts! And the droughts severely hurt their ability to produce those crops.
CALLI: And another big reason we hear about California’s water troubles so often is their unique climate and weather situation. The majority of California’s rain and snow falls in the northern half, but around eighty percent of their water usage is down in southern California.
NATE: That must require a lot of transporting.
CALLI: Indeed. The areas that need it most, don’t have enough of it! And all that combines to make California an interesting state to look at with regard to how they’re addressing water shortages on a grand scale. Now, the state government puts into place sweeping conservation mandates when needed, like the ones earlier this year requiring local water agencies to reduce usage by twenty percent, and making it illegal to water decorative lawns on commercial properties with potable water. But they’re looking at other solutions, bigger ones, more future-minded ones. So, what we’re talking about today is a solution that addresses the vast infrastructure California has in place to get all that water where it needs to go.
NATE: That makes sense. How does that work in the first place? How do they do it?
CALLI: Your first guess probably wouldn’t have been the four thousand miles of canals they have running through the state.
NATE: I was going to say the water fairy. But canals are way cooler.
CALLI: And real. The canals are part of an absolutely massive state water project, serving fresh water to around thirty-five million people and six million acres of farmland. The water is transported from rivers in northern California and distributed south to places up to 400 miles away. In addition to over twenty dams and some stretches of underground tunnels, the majority of the system is made up of these large above-ground canals, about 300 miles worth. The canals are typically about forty feet wide and thirty feet deep, though it varies throughout the system. The canals work great overall, but they do have a pretty big design issue - evaporation.
NATE: But isn’t that completely natural?
CALLI: Yes but in this instance it is problematic. The canals actually lose an estimated one to two percent of their haul a year to evaporation.
NATE: That sounds like it’s doing great. If I got a ninety-eight on a test, I was thrilled.
CALLI: It’s not great when it’s scaled up. A mere one percent loss can equate to a yearly loss of sixty-five billion gallons.
NATE: Okay yeah no that’s bad...
CALLI: It’s enough water to supply two million people or fifty thousand acres of farmland. But there’s a fix on the way!
NATE: Ooo I love fixes!
CALLI: There’s a proposal to cover the canals with solar panels. Which would not only reduce the evaporation, but also generate enough electricity to make up half of California’s renewable energy goals for the next twenty years.
NATE: That’s genius! It also reminds me of the story we had earlier this year on solar-panel covered rooftop gardens.
CALLI: Yes, it’s very similar! The shade from the solar panels should reduce evaporation, and the water below would cool the panels, which would help them be up to three percent more efficient. The project will generate lots of electricity to be put into the power grid, but as a bonus, the design could have the energy stored and used locally. And the less the energy has to travel along the grid, the less is lost along the way.
NATE: So, this program is in motion? Happening already?
CALLI: Right now there’s a proof of concept being developed under the name Project Nexus.
NATE: Coolest name ever.
CALLI: The project has three sites where mile-long installations will be tested. The data collected can be used to expand developments across the state. And with the environmental necessity for these panels, their efficiency, and their economic value - it may not be long until we see more panel-equipped canals developed throughout the entire western U.S.
NATE: California needs it most, but others could use it too. With the rising temperatures, other places may find it necessary soon.
CALLI: Yeah, it may seem like an issue contained to only one part of the country - but the damaging effects of the droughts extend to every corner of the U.S.
NATE: Suddenly my mouth is dry and I’m thirsty. I’m glad to know that people are working hard to save water any way they can.
CALLI: You and me both.
[SFX: Whoosh]
NATE: Calli, I’ve got amazing news that could help us realize our dreams of human exploration in the depths of space.
CALLI: You know how much I love space exploration, what problem are we tackling today?
NATE: Space food, and I’m not talking about astronaut ice cream. Researchers just successfully grew plants in Moon regolith (fancy word for dirt) for the first time! They’re thrilled because being able to grow food on the moon could make farther and longer space missions a whole lot easier.
CALLI: Oh that's so cool! Where did we get the dirt to try the experiment?
NATE: Researchers borrowed dirt from NASA that astronauts brought back from the moon during the Apollo 11, 12 and 17 missions.
CALLI: Earth plants, moon soil. That's a crossover I can get behind.
NATE: It's not actually the first time they’ve interacted! When astronauts first came back from the moon, we were super concerned about potentially contaminating the earth with bacteria or some unknown harmful substance from the moon. The Apollo 11 crew even spent 3 weeks in quarantine after their mission to make sure they were safe! One of our tests to relieve these fears, and make sure moon dust wouldn’t kill us, was to sprinkle earth plants with regolith to make sure they didn’t die at the hands of some moon disease.
CALLI: Those brave plants. Did we do more soil sprinkling in this test?
NATE: Nope, we planted seeds! The study was actually stunningly simple for how monumental this news feels. But there was a big hurdle, they only had 12 grams of soil to plant in.
CALLI: 12 grams?! That’s only the weight of three nickels!
NATE: Right, it's a tiny amount of regolith. So researchers had to get clever, and economical. They put the soil in thimble-sized wells in plastic plates, like tiny planting pots.
CALLI: A micro garden: cool. A micro space garden? Super cool.
NATE: Super cool indeed. The scientists placed a few seeds from a plant called Arabidopsis in each well. Many researchers use this plant in studies because we have completely mapped its genetic code. That means we can watch how the plants grow in the lunar soil, and look at how the regolith might affect the plants’ genetics. They then moistened the micro moon pots, and gave them a nutrient mixture.
CALLI: How did they make a control group if they had so little soil?
NATE: Researchers also simulated lunar, martian, and terrestrial soil. But at the end of the study, nearly all the seeds planted in the real lunar regolith sprouted!
CALLI: That’s incredible! Good for you plants! But were they healthy plants or had the regolith changed them?
NATE: Well they found that the soil had no effect on hormones or signals involved in germination, but they were still definitely affected by the regolith. The plants were smaller, they grew more slowly, and they didn’t all grow to the same size. When researchers looked at the genetic info, they saw that the plants were reacting to a stressful environment.
CALLI: Poor little fellas. But who can blame them, that’s not a nice rich compost heap, its barren moon dirt!
NATE: Right. But this proves we can grow plants in space soil, and now we can try to create environments in lunar soil that are even more conducive to growing. It's a big step toward creating food and oxygen on the moon.
CALLI: And if we can grow plants on the moon, we could live up there so much more easily. And have food that much closer to other planets like Mars!
NATE: Right. This could be a huge help for future space missions, including the Artemis missions to Mars, that might use the moon as a staging area and launch pad.
CALLI: You can’t go on any long journey without a full stomach!
[SFX: Whoosh]
NATE: Let’s recap what we learned today to wrap up.
CALLI: Research shows that symmetry in nature may be one of biology’s fundamental laws of operation. Asymmetry can win out from time to time via natural selection, but symmetry rules the day. In the end it’s easier for the mechanisms that build life to copy and paste existing patterns rather than come up with something totally new every time.
NATE: A new proposal to cover California’s state-wide water canals with solar panels could lead to huge economic, energy, and water conservation benefits. Test models are expected to begin shortly, with the results having broad implications for fighting the current megadrought in the western U.S. and its effects around the country.
CALLI: Scientists successfully grew plants in moon soil for the first time. While they were not the biggest, strongest, or most edible plants, it's an important first step in food and oxygen production on the moon. Further success could open big doors for future space missions.