(repeat) Without sand, engineering would be stuck in the Middle Ages. Wooden houses would line mud-packed streets, and Silicon Valley would be, well, just a valley. Sand is the building material of modern cities, and we use more of this resource than any other except water and air. Now we’re running out of it.
Hear why the Roman recipe for making concrete was lost until the 19th century, and about the super-secret mine in North Carolina that makes your smartphone possible.
“Diversity or die” could be your new health mantra. Don’t boost your immune system, cultivate it! Like a garden, your body’s defenses benefit from species diversity. Find out why multiple strains of microbes, engaged in a delicate ballet with your T-cells, join internal fungi in combatting disease. Plus, global ecosystems also depend on the diversity of its tiniest members; so what happens when the world’s insects bug out?
Guests:
(repeat) Are you ready to defer all your personal decision-making to machines? Polls show that most Americans are uneasy about the unchecked growth of artificial intelligence. The possible misuse of genetic engineering also makes us anxious. We all have a stake in the responsible development of science and technology, but fortunately, science fiction films can help.
(repeat) The Earth is not round. Technically, it’s an oblate spheroid. But for some people, the first statement is not even approximately correct. Flat Earthers believe that our planet resembles – not a slightly squashed grapefruit – but a thick pancake. A journalist who covered a Flat Earth convention describes the rationale behind this ever-more popular belief.
So how do you establish science truth? We look at the difference between a truly scientific examination of extraordinary claims and approaches that feel and look science-y but aren’t.
Crowded subway driving you crazy? Sick of the marathon-length grocery store line? Wish you had a hovercraft to float over traffic? If you are itching to hightail it to an isolated cabin in the woods, remember, we evolved to be together. Humans are not only social, we’re driven to care for one another, even those outside our immediate family.
If you bake, you can appreciate math’s transformative properties. Admiring the stackable potato chip is to admire a hyperbolic sheet. Find out why there’s no need to fear math - you just need to think outside the cuboid. Also, how nature’s geometric shapes inspire the next generation of squishy robots and an argument for radically overhauling math class. The end point of these common factors is acute show that’s as fun as eating Pi.
Guests:
(repeat) Heredity was once thought to be straightforward. Genes were passed in an immutable path from parents to you, and you were stuck – or blessed – with what you got. DNA didn’t change.
But now we know that’s not true. Epigenetic factors, such as your environment and your lifestyle, control how your genes are expressed. Meanwhile, the powerful tool CRISPR allows us to tinker with the genes themselves. DNA is no longer destiny.
Neil, Buzz, and Michael made it look effortless, but the moon landing was neither easy nor inevitable. Soon after President Kennedy publicly stated the goal of sending Americans to the moon, NASA confessed that the chances of success were only about 50/50. But on July 20, 1969, despite enormous difficulties, astronauts stepped onto the lunar regolith.
Laughing rats, sorrowful elephants, joyful chimpanzees. The more carefully we observe, and the more we learn about animals, the closer their emotional lives appear to resemble our own. Most would agree that we should minimize the physical suffering of animals, but should we give equal consideration to their emotional stress? Bioethicist Peter Singer weighs in. Meanwhile, captivity that may be ethical: How human-elephant teamwork in Asia may help protect an endangered species.
Guests:
(repeat) SMS isn’t the original instant messaging system. Plants can send chemical warnings through their leaves in a fraction of a second. And while we love being in the messaging loop – frenetically refreshing our browsers – we miss out on important conversations that no Twitter feed or inbox can capture. That’s because eavesdropping on the communications of non-human species requires the ability to decode their non-written signals.
(repeat) There’s evidence for a subsurface lake on Mars, and scientists are excitedly using the “h” word. Could the Red Planet be habitable, not billions of years ago, but today? While we wait – impatiently – for a confirmation of this result, we review the recipe for habitable alien worlds. For example, the moon Titan has liquid lakes on its surface. Could they be filled with Titanites?
(repeat) Okay you animals, line up: stoned sloths, playful pandas, baleful bovines, and vile vultures. We’ve got you guys pegged, thanks to central casting.
Or do we? Our often simplistic view of animals ignores their remarkable adaptive abilities. Stumbly sloths are in fact remarkably agile and a vulture’s tricks for thermoregulation can’t be found in an outdoors store.
Poisonous snakes, lightning strikes, a rogue rock from space. There are plenty of scary things to fret about, but are we burning adrenaline on the right ones? Stepping into the bathtub is more dangerous than flying from a statistical point of view, but no one signs up for “fear of showering” classes.
Find out why we get tripped up by statistics, worry about the wrong things, and how the “intelligence trap” not only leads smart people to make dumb mistakes but actually causes them to make more.
Guests:
(repeat) The seas are rising. It’s no longer a rarity to see kayakers paddling through downtown Miami. By century’s end, the oceans could be anywhere from 2 to 6 feet higher, threatening millions of people and property. But humans once knew how to adapt to rising waters. As high water threatens to drown our cities, can we learn do it again.
A new theory about life’s origins updates Darwin’s warm little pond. Scientists say they’ve created the building blocks of biology in steaming hot springs. Meanwhile, we visit a NASA lab where scientists simulate deep-sea vent chemistry to produce the type of environment that might spawn life. Which site is best suited for producing biology from chemistry?
The catastrophic explosion at the Chernobyl nuclear power plant in April 1986 triggered the full-scale destruction of the reactor. But now researchers with access to once-classified Soviet documents are challenging the official version of what happened both before and after the explosion.
(repeat) DNA is the gold standard of identification. Except when it’s not. In rare cases when a person has two complete sets of DNA, that person’s identity may be up in the air. Meanwhile, DNA ancestry tests are proving frustratingly vague: dishing up generalities about where you came from rather than anything specific. And decoding a genome is still relatively expensive and time-consuming. So, while we refine our ability to work with DNA, the search is on for a quick and easy biomarker test to tell us who we are.
Your virtual assistant is not without a sense of humor. Its repertoire includes the classic story involving a chicken and a road. But will Alexa laugh at your jokes? Will she groan at your puns?
Telling jokes is one thing. Teaching a computer to recognize humor is another, because a clear definition of humor is lacking. But doing so is a step toward making more natural interactions with A.I.
(repeat) Dinosaurs are once again stomping and snorting their way across the screen of your local movie theater. But these beefy beasts stole the show long before CGI brought them back in the Jurassic Park blockbusters. Dinosaurs had global dominance for the better part of 165 million years. Compare that with a measly 56 million years of primate activity. We bow to our evolutionary overlords in this episode.
Solid materials get all the production credit. Don’t get us wrong, we depend on their strength and firmness for bridges, bones, and bento boxes. But liquids do us a solid, too. Their free-flowing properties drive the Earth’s magnetic field, inspire a new generation of smart electronics, and make biology possible. But the weird thing is, they elude clear definition. Is tar a liquid or a solid? What about peanut butter?