Science Friday

Just about every day there’s a new headline about artificial intelligence. OpenAI Founder and CEO Sam Altman was forced out, and then dramatically returned to his post—all in the span of a week. Then there’s the recent speculation about a revolutionary new model from the company, called Q*, which can solve basic math problems.

Beyond the inner workings of AI’s most high profile startup are stories about AI upending just about every part of society—healthcare, entertainment, the military, and the arts. AI is even being touted as a way to help solve the climate crisis.

How did we get to this moment? And how worried or excited should we be about the future of AI? No matter how it all shakes out, AI leader and early innovator Dr. Fei-Fei Li argues that humans should be at the center of the conversation and the technology itself.

Ira talks with Dr. Fei-Fei Li, founding director of the Institute for Human-Centered AI at Stanford University and author of the book The Worlds I See: Curiosity, Exploration and Discovery At The Dawn of AI, about her path from physics to computer science and the promise and potential of human-centered artificial intelligence.

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The United Nations Climate Change Conference, COP28, began this week in Dubai. This is an annual event, where leaders and delegates from around the world come together to discuss how to collaboratively reach important milestones for the future of the planet. Goals like slowing the rise of temperatures on Earth will require buy-in from all major players to be successful.

But this week, a document leaked that showed the United Arab Emirates planned something at odds with the event: promotion of the oil and gas industries. This has led to increased skepticism of COP and its goals among both critics and attendees.

Ira is joined by Tim Revell, deputy US editor of New Scientist, to talk about this story. Plus, how a single bitcoin transaction uses enough water to fill a swimming pool, the way nutrients in soil drive biodiversity, and how amino acids could be formed alongside stars.

If you were in the eastern United States during the summer of 2021, you likely heard the incessant, whirring buzz caused by the mass emergence of Brood X periodical cicadas. That event, which occurs once every 17 years, brought forth countless cicadas to shed their skins, mate, lay eggs, and die. But it turns out their arrival wasn’t just something that you could witness out the lawn or against your car windshield. The sound of their emergence was something that could be detected by fiber-optic cables.

Dr. Sarper Ozharar, a researcher who studies optical networking and sensing at NEC Labs in Princeton, New Jersey, has worked on techniques using fiber-optics to sense the vibrations of things like traffic, sirens, and gunshots. Loud noises produce vibrations that subtly distort optical “backscatter” within a glass fiber-optic cable. Using AI, researchers can decode those vibrations and determine what, and where, a noise may have occurred near the fiber.

In the summer of 2021, Ozharar and colleagues detected an unusual frequency signal in their test data. With the help of entomologist Dr. Jessica Ware of the American Museum of Natural History, they eventually determined that it was the whirring of the cicada swarm. Their find is the topic of a report published this week in the Journal of Insect Science.

Ozharar joins Ira Flatow to talk about how fiber-optic sensing works, and how an electronics and communications lab ended up publishing in an entomology journal.

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It’s hard to imagine a world without seatbelts or airbags. But five decades ago, it was the norm for car manufacturers to put glamour over safety.

“It was stylistic pornography over engineering integrity,” Ralph Nader, prolific consumer advocate and several-time presidential candidate, tells Science Friday.

This winter marks the 55th anniversary of Nader’s groundbreaking investigation, “Unsafe at Any Speed,” a damning look at how little auto safety technology was in vehicles back in the 1960s. The book had a massive effect on auto safety in the U.S., setting the groundwork for laws about seatbelts, and the creation of the United States Department of Transportation.

Nader joins Ira to discuss what’s happened over 55 years of auto safety advances, and what kind of work is needed to make sure new technology, like self-driving cars, have the safety checks they need before going out on the roads.

To stay updated on all things science, sign up for Science Friday's newsletters. Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

If you want to predict the color of something, you can talk about wavelengths of light. Light with a wavelength of around 460 nanometers is going to look blue. If you want to predict what something sounds like, frequencies can be a guide—a frequency of around 261 Hertz should sound like the musical note middle C. 

Predicting smells is more difficult. While we know that many sulfur-containing molecules tend to fall somewhere in the ‘rotten egg’ or ‘skunky’ category, predicting other aromas based solely on a chemical structure is hard. Molecules with a similar chemical structure may smell quite different—while two molecules with very different chemical structures can smell the same. 

This week in the journal Science, researchers describe developing an AI model that,  given the structure of a chemical compound, can roughly predict where it’s likely to fall on a map of odors. For example, is it grassy? Or more meaty? Perhaps floral?

Dr. Joel Mainland is one of the authors of that report. He’s a member of the Monell Chemical Senses Center and an adjunct associate professor in the department of neuroscience at the University of Pennsylvania in Philadelphia. Mainland joins Ira to talk about the mystery of odor, and his hope that odor maps like the one developed by the AI model could bring scientists closer to identifying the odor equivalent of the three primary colors—base notes that could be mixed and blended to create all other smells. 

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Few living scientists are as iconic as Dr. Jane Goodall. The legendary primatologist spent decades working with chimpanzees in Tanzania’s Gombe National Park. More recently, Goodall has devoted her time to advocating for conservation, not just in Africa, but worldwide.

Ira spoke with Goodall in 2002, after she had published her book The Ten Trusts: What We Must Do to Care for the Animals, and an IMAX film about her work with chimpanzees had just been released. 

To stay updated on all things science, sign up for Science Friday's newsletters. Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Ever wondered why your dog’s back-and-forth shaking is so effective at getting you soaked? Or how bugs, birds, and lizards can run across water—but we can’t? Or how about why cockroaches are so darn good at navigating in the dark?

Those are just a few of the day-to-day mysteries answered in the new book How to Walk on Water and Climb Up Walls: Animal Movement and the Robots of the Future, by Georgia Tech mathematician David Hu.

The book answers questions you probably won’t realize you even had, but they’re questions with serious answers that span the worlds of physics, fluid mechanics, and biology. Throughout the book, Hu demonstrates the extraordinary value day-to-day curiosity brings to science.

But, while he explores how science can reveal wonders of the mechanisms in our world, Hu writes how his work has been the target of politicians for so-called “wasteful” science spending. One of the studies under attack, an inquiry into the average length of urination across the animal kingdom, might have had a laughable premise, but eventually led to serious attention by urologists and researchers working on treatments, prostheses, and artificial organs.

“The concept of waste is based on the notion of a limited gas tank and a single known destination,” Hu writes. “People expect scientists to save gas as they go from A to B. But the real power of science is to take us to destinations that we have never been to.”

To stay updated on all things science, sign up for Science Friday's newsletters. Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

In science, there are some traditions: Every October, the Nobel Prize committee announces the winners of that year’s awards, which are presented in Sweden in December. And every September for the past 33 years, a different committee has awarded the Ig Nobel Prizes in Cambridge, Massachusetts. And every year, on the day after Thanksgiving, Science Friday plays highlights from the awards ceremony. 

The Ig Nobel awards are a salute to achievements that, in the words of the organizers, “make people laugh, then think.” They are presented by the editors of the science humor magazine Annals of Improbable Research to 10 lucky(?) winners for unusual achievements in science, medicine, and other fields. This year’s ceremony was held virtually, with a webcast taking the place of the traditional raucous ceremony in Harvard’s Sanders Theater. However, it still contained many elements of the in-person Igs, from flying paper airplanes to the participation of real Nobel Laureates in the ceremony. 

This year’s awards included prizes for explaining why many scientists like to lick rocks,  for re-animating dead spiders to use as mechanical gripping tools, and for using cadavers to explore whether there is an equal number of hairs in each of a person’s two nostrils. SciFri producer Charles Bergquist joins Ira to discuss highlights from this year’s ceremony.

You could be flushing important information about your health right down the toilet—quite literally. Pee and poop can tell you a lot about your health, so what if your waste…didn’t go to waste? What if, instead, it could tell you more about your health? Like number one, it can catch a condition like diabetes early. Or number two, check out what’s going on in your gut microbiome.

That’s the goal of the smart toilet—a device that gets all up in your business to tell you more about your health. Ira talks with the inventor of the PH Smart Toilet, Dr. Seung-min Park, instructor of urology at Stanford’s School of Medicine in California, about how the toilet works, how it can be used to catch diseases early on, and the ethical implications of such a device.

To stay updated on all things science, sign up for Science Friday’s newsletters. Transcripts for each segment will be available after the show airs on sciencefriday.com.

Reporter Ashley Ahearn bought a wild horse from the federal government for $125. Also, with opera and visual art, an exhibit looks at modern genetic engineering of pigs.

Wild mustangs are an icon of the American West, conjuring a romantic vision of horses galloping free on an open prairie. But in reality, the Bureau of Land Management (BLM) says the sensitive Western ecosystem can’t handle the existing population of horses.

There are about 80,000 wild horses in the American West, a number that grows about 10-20% each year. The BLM says the fragile, arid rangelands the horses occupy can only support a third of that number before they overgraze habitats critical for other species. This has led to controversial roundups to get wild horses off the open range.

Science and environment reporter Ashley Ahearn dove deep into the history, symbolism, and ecological impact of the West’s mustangs for the new podcast Mustang. She even adopted a wild horse, named Boo, from the federal government for $125. Ashley speaks with guest host Flora Lichtman about her boots-on-the-ground reporting, and what she learned from how tribal nations manage mustangs.

Over 100,000 people are waiting for organ donations in the United States. Many will likely never receive one, since there are so few available. So scientists are turning to pigs for potential alternatives. Their organs are remarkably similar to ours, and scientists are now using CRISPR to modify pigs’ DNA to improve transplantation outcomes. But although the field has shown major advances in the last decade, the technique isn’t ready yet. Recently, a patient who received a modified pig heart died six weeks after the surgery.

Artist Heather Dewey-Hagborg was intrigued by these recent advances, and looked into humanity’s history of modifying the pig over thousands of years for her new gallery exhibit, Hybrid: an Interspecies Opera. For the work, she interviewed scientists and archaeologists and even filmed in a lab that’s experimenting with genetically modifying pigs to create more human-compatible organs.

In the resulting documentary, which plays in the exhibit, the words from the scientists she interviewed are transposed into an opera composed by musician Bethany Barrett. Visitors can also find 3D-printed clay pig statues and a timeline of how humans have transformed pigs over ten millennia, thanks to selective breeding.

Dewey-Hagborg sat down with SciFri producer D. Peterschmidt to talk about how the exhibit came together, and how CRISPR could further transform pigs and our relationship to them. 

To stay updated on all things science, sign up for Science Friday's newsletters. Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

It’s hard to imagine, but the moon we all know and love hasn’t always been in the sky. Like all of us, the moon has an age. Until recently, our lunar neighbor has been estimated to be about 4 billion years old.

But new research on lunar crystals from the Apollo 17 mission has helped researchers pinpoint a more specific age for the moon—and it’s about 40 million years older than previously thought.

That difference may sound like a drop in the bucket given the time scales, but lead study author Dr. Jennika Greer says this is a big deal, because it tells us more about what the solar system was like in its earlier years. Greer, a postdoctoral researcher at the University of Glasgow in Scotland, joins guest host Flora Lichtman to talk about her methods and why the early universe was so fascinating.

It’s sweater season once again, but you may have noticed that some of your newer sweaters aren’t standing the test of time. Perhaps they are pilling, unraveling, or losing their shape. But if you look at sweaters from the ‘80s or ‘90s, they may still look brand new. Last month, an article by Amanda Mull in the Atlantic about declining sweater quality made the rounds online, and we wanted to know more.

What, scientifically, went wrong in sweaters? And why are sweaters so bad now?

Guest host Flora Lichtman unravels the science of sweaters with Dr. Imran Islam, knit expert and assistant professor at the Fashion Institute of Technology in New York City. They chat about the fibers that make up sweaters, what physics has to do with how long they last, and what to look for when purchasing knitwear.

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Gift-giving season is upon us once again! And if you’re not sure what to get the kids in your life, we’re here to help. Many new STEM books for kids and young adults came out this year, and we asked a few experts to tell us about their favorites from 2023.

Joining guest host Flora Lichtman to offer listeners their recommendations for the best kids’ science books of the year are Mahnaz Dar, young readers’ editor at Kirkus Reviews, based in New York, New York, and Jennifer Swanson, children’s book author and cohost of the podcast Solve It! for Kids, based in Jacksonville, Florida.

You can download a printable list of our guests’ recommendations to take with you on your shopping trip.

To stay updated on all things science, sign up for Science Friday's newsletters. Transcripts for each segment will be available the week after the show airs on sciencefriday.com.