

Science Friday
Science Friday and WNYC Studios
Covering the outer reaches of space to the tiniest microbes in our bodies, Science Friday is the source for entertaining and educational stories about science, technology, and other cool stuff.
Episodes
Mentioned books

May 28, 2021 • 47min
Sand Sustainability, Jane Goodall, Morphing Pasta, Cicada Snacks. May 28, 2021, Part 2
Shifting The Sand Business To Greener Practices
Sand is one of the most in-demand natural materials on the planet—some 50 billion tons of sand and gravel are mined every year. It’s because the humble sand is a key ingredient in many materials, from concrete and asphalt to microchips and glass. But sand is also heavy, needed in large quantities, and costly to ship—meaning that in some regions, local demand for sand outstrips supply. A ‘sand mafia’ exists in parts of the globe, and in others, international conflicts have arisen over accusations of illicit cross-border beach theft.Dr. Aurora Torres, a postdoctoral researcher in Michigan State University’s Center for Systems Integration and Sustainability and at the Catholic University of Louvain, joins host John Dankosky to talk about ways to make the business of sand extraction more ecologically-friendly—from manufacturing sand via high-tech rock crushing machines to reducing demand by recycling construction materials.
A Trip Back In Time With Jane Goodall
On September 27, 2002, Ira sat down for his first interview with the pioneering conservationist and primatologist Jane Goodall, to hear about her life, work, and vision for our relationship with our environment. Goodall is the 2021 recipient of the prestigious Templeton Prize for her work with animals and her contributions to humanity.
When this interview originally aired, Goodall was already 40 years distant from her initial breakthrough discovery of tool use in chimpanzees, was the subject of a newly released IMAX movie, and had just been named a UN Ambassador for Peace.
Learn more about her in the latest Science Friday Rewind, a series exploring historic interviews and scientific discoveries captured in our audio archives.
A Bowl Full Of Pasta Engineering
When you walk down the pasta aisle at the supermarket, there are so many tasty choices: There’s the humble spaghetti, the tubes of ziti, the tiny shells, and the butterfly-like farfalle. But every pound of pasta is not created equal—some of the boxes pack mostly air.In recent work published in the journal Science Advances, Dr. Lining Yao of Carnegie Mellon’s Morphing Matter Lab and her colleagues discuss an innovative way to solve the problem of puffed-up pasta boxes: What if different pasta shapes could be flat-packed into containers like DIY IKEA furniture? The researchers developed a way to map out tiny grooves and ridges on the surface of a flat noodle sheet. When the pasta is cooked in hot water, it swells at different rates around the ridges and grooves, causing it to fold on its own into shapes such as boxes, rose-like flowers, and helix curls. Yao joins SciFri’s Charles Bergquist to talk about the research, and the challenges of making your dinnertime pasta plate into an origami craft project.
How To Take A Bite Of The Brood X Cicada Swarm
After 17 years underground, billions, maybe even trillions, of cicadas are finally emerging in a group that scientists are calling Brood X. The cicadas will mate and die all within about six weeks—filling the air with a collective hum, and leaving behind their exoskeletons.
For some this might sound like a horror movie, but for Bun Lai, chef at Miya’s Sushi in Connecticut, he sees this as an opportunity for a sustainable snack. He talks about how to hunt and cook a cicada, and how they fit in as a sustainable food source.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

May 28, 2021 • 47min
Vaccine Hesitancy, Colorado River Drought, Alternative Syrups. May 28, 2021, Part 1
How Do We Overcome Vaccine Hesitancy?
This Memorial Day weekend, many people will be traveling to the beach, hitting the road or socializing with friends—maskless—for the first time in over a year. As of this week, 50% of people over 18 are now fully vaccinated. Another 15 to 20% of people are taking a “wait and see” approach. Of those still on the fence, some are concerned about the vaccine’s side effects; others have a long standing mistrust of the institutions responsible for the vaccine rollout.
In order to fully end the pandemic, public health officials will have to find a way to get the vaccine-hesitant on board. Dr. Gary Bennett, professor of psychology and global health at Duke University sheds light on the hurdles that must be overcome.
And a new segment of the population can now receive the Pfizer vaccine: children 12 years and older, after the Centers for Disease Control and Prevention gave approval in mid-May.
But many American parents don’t want their children vaccinated at all—including for measles or the flu. One recent report from this past April showed that over 30% of parents would wait to get their child vaccinated—nearly double the percentage of adults who were hesitant. Matthew Simonson, a doctoral candidate at Northwestern University and lead author on the report, joins us to break down the numbers.
What Happens When The Colorado River Runs Dry?
Dry conditions are the worst they’ve been in almost 20 years across the Colorado River watershed, which acts as the drinking and irrigation water supply for 40 million people in the American Southwest.
As the latest round of federal forecasts for the river’s flow shows, it’s plausible, maybe even likely, that the situation could get much worse this year.
Understanding and explaining the depth of the dryness is up to climate scientists throughout the basin.
Read the full article at sciencefriday.com.
Making Syrup From More Than Maple Trees
Researchers at the University of New Hampshire are studying new ways to make syrup out of the northern forest—not from maple trees, but from beeches, birches, sycamores and more. They want to create new markets for an industry that, right now, depends on just one kind of tree—making it vulnerable to disease and climate change.
At the tail end of maple sugaring season, other kinds of sap were still flowing freely in the woods of Lee. UNH researcher David Moore had sensors plugged into a stand of beech trees to measure that sap and the conditions helping produce it.
“You can see I have three trees with sensors here that are all tied back to one data logger,” Moore said, pointing to the tubes and wires running from the beech trunks. Nearby, a bucket collected the resulting sap, while other equipment gathered weather data.
Researchers say monocultures, like the all-maple syrup industry, are more at risk from climate change, pests and other unpredictable threats. So Moore sees untapped potential in other common species, like the American beech. It’s found throughout New Hampshire’s forests, farms and sugar bushes—almost like a tree weed. “If you can think of some economical use—if you can make syrup from them, that would be a nice way to actually generate a little profit from them,” Moore said.
Read the full article at sciencefriday.com.
Big Oil Reckons With Climate Change
Depending on your perspective, Wednesday was a bad day to be an oil company, or a good day to be a climate activist. Three major oil companies had climate change pushed higher on their agendas: Shell was ordered by a Dutch court to cut its greenhouse gas emissions 45% by 2030; Chevron was told by its shareholders to reduce not just its emissions from oil production, but also those of its customers; and at Exxon’s annual shareholder meeting, a small advocacy firm managed to score two, and possibly three, spots on its board of directors.
So where did these climate coups come from, and what could come next? Vox staff writer Umair Irfan talks to John Dankosky about this week’s wins for the planet, as well as the limits of such reforms.
Plus other stories from the week, including Moderna’s promising COVID-19 vaccine results in adolescents aged 12-17, and President Biden’s call for more investigation into COVID-19’s origins.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

May 21, 2021 • 48min
Cybersecurity, Baseball Physics, Opioid Trial. May 21, 2021, Part 2
Americans’ Online Security Needs An Update
Last week, all eyes were on the shutdown of a gas pipeline that delivered fuel to large portions of the Southeastern US. The shutdown was not due to a leak or planned pipeline maintenance, but to a ransomware attack that took billing computers at the pipeline operator offline. The attack had encrypted data on those computers, rendering the data unusable to the pipeline operator until they paid a ransom.In recent years, similar ransomware attacks have affected other significant industries, from computers in a hospital cancer clinic to the Irish health system. Cybersecurity specialist Katie Moussouris, founder and CEO of Luta Security, joins Ira to talk about what’s behind the rise of ransomware attacks, and what businesses need to do to lessen their risks. Among the causes, she says, are increasing availability of anonymous money transfers via cryptocurrency, nation-states that sometimes turn a blind eye to hacking activities, and businesses who grow quickly without expanding their security to match.
In West Virginia, Opioid Distributors Are Finally On Trial
A trial is underway in West Virginia against the nation’s three largest opioid distributors: Cardinal Health, AmerisourceBergen, and McKesson. The companies are accused of funneling massive amounts of painkillers to West Virginia communities, fueling the opioid crisis that has devastated parts of the region.
By some measures, Cabell County has the worst drug overdose rate in the country, and its rate of overdose deaths is six times the national average. While the companies say the doctors who prescribed the pills are to blame, this trial is a community’s attempt to hold the massive companies accountable. The city of Huntington, West Virginia and the Cabell County Commission brought the case against the companies.
Joining Ira to talk about this trial and what led up to it is Eric Eyre, investigative reporter at Mountain State Spotlight in Charleston, West Virginia. Eric won a 2017 Pulitzer Prize for his reporting on the opioid epidemic in West Virginia, and is the author of the book Death in Mud Lick: A Coal Country Fight Against the Drug Companies That Delivered the Opioid Epidemic.
Video Game Skills May Make Better Surgeons
The classic board game Operation—in which players try to use conductive tweezers to remove a patient’s funny bone and other ailing imaginary organs—may not be the best tool for training real life surgeons for the operating room. But according to a recent paper published in the journal Surgery, playing video games may have a benefit for training surgeons in specific medical fields.
Arnav Gupta, a third-year medical student at the University of Ottawa and co-author of the study, told Ira that the largest benefits of gaming seemed to come in two specific areas. Gains seen in robotic surgery skills might be due to the similarity of the robotic controls to a game controller joystick. Improvements in laparoscopic surgery, where surgeons operate using instruments inserted through tubes in a thin slit in a patient, may increase doctors’ ability to translate images on a screen to three-dimensional movements. (The researchers didn’t see major improvements in other types of surgery.) Gupta discusses the research with Ira, as well as possible next steps for ways gaming could improve medical training.
What A Rare Baseball Collision Tells Us About The Physics Of The Game
Recently during a pre-game warmup, Phillies right fielder Bryce Harper was doing some batting practice when he hit a line drive to right field, and it collided with another ball in midair.
It was an extremely rare event we’ll probably never see again. But if someone were to try and duplicate the collision, would physics work in their favor?
Ira is joined by Rhatt Allain, assistant professor of physics at Southeastern Louisiana University and writer for Wired’s Dot Physics blog, for a quick back of the envelope discussion. Plus, baseball players and fans are learning more about the physics of the game—exit velocity and launch angle are now statistics that people can calculate and tally. Dr. Alan Nathan, professor emeritus of physics at University of Illinois and professional baseball consultant, talks about how physics is changing how America’s pastime is played.
The Resonating Room Tones Of Composer Alvin Lucier
Alvin Lucier is one of the giant figures in experimental, electronic and electro-acoustic music, known for “making the inaudible…audible.”
Last week, he turned 90, and the celebration included a 27 hour marathon of his most famous piece, “I Am Sitting In A Room.” The piece, first recorded in 1969, is very simple in concept but deceptively complex. It consists of a short passage of text, read aloud in a room. That sound is recorded and then played back into that same room, picked up by the same microphone, over and over, until the room resonance renders the speech otherworldly and unintelligible.
"I Am Sitting In A Room" has been performed around the world, and has even prompted a series of adaptations by YouTubers, including one who uploaded his video 1,000 times, resulting in bizarre video degradation over time. Lucier’s work has been academically studied for years, and presented and championed at MIT’s Media Lab in seminars devoted to the “quality of sound as experience.”
Listen to his work and a SciFri Soundscape of the music.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

May 21, 2021 • 47min
Global Vaccination, Malaria Vaccine, Zombie Wildfires. May 21, 2021, Part 1
How Do You Solve a Problem Like World Vaccination?
Here in the U.S., it feels as if we’ve turned a corner in the COVID-19 pandemic. Most of the population can be vaccinated, and restrictions for masks and distancing are loosening. But we won’t be able to get a handle on the pandemic until the rest of the world has access to a vaccine. If you thought distributing shots to rural areas here in the U.S. was hard, imagine distributing them to every corner of the globe.
President Joe Biden this week pledged to send an additional 20 million vaccine doses abroad, bringing the total promised to 80 million. But the U.S. is hardly the only country that plans to share doses. So where does the world vaccination effort stand?
One international effort, led by organizations including the World Health Organization and UNICEF, is called COVAX, or COVID-19 Vaccines Global Access. Joining Ira to discuss this effort is implementation team member Dr. Bruce Aylward, senior advisor to the Director-General at the World Health Organization. Ira also speaks to medical supply chain expert Prashant Yadav, senior fellow at the Center for Global Development and professor at the INSEAD Business School, based in Washington, D.C.
Can A New Vaccine Put An End To Malaria?
The World Health Organization estimates that every two minutes, a child somewhere in the world dies of malaria. As of 2018, the parasite-induced disease kills a total of more than 400,000 people every year—most of them children under the age of five in sub-Saharan Africa.
While the quest for a malaria vaccine is more than 50 years old, there is still no licensed, fully approved option. The closest to approval, called RTS,S, is being piloted in several countries, with efficacy estimates hovering around 56 percent.
But after a new vaccine, called R21, demonstrated more than 75% efficacy in a small trial in Burkina Faso, is there hope for a more efficient push to reduce the global burden of malaria?
Ira talks to malaria vaccine researcher Prakash Srinivasan and Biden administration malaria coordinator Raj Panjabi about the implications of a vaccine milestone—and the work remaining ahead. Plus, how the COVID-19 pandemic might inform future progress in global health.
Zombie Wildfires Can Rage On For Months
Wildfires are becoming more intense. California saw a record breaking wildfire season—burning 4 million acres across the state last year. Scientists say there is an increase in another type of wildfires called “zombie wildfires.” Forest fires that ignite in the summer and pop back up during the spring.
Roxanne Khamsi talks about a new study that tracks the occurrence and causes of these wildfires. Plus, a look at a “black fungus” infection COVID-19 patients in India.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

May 14, 2021 • 48min
NFTs and Art, Neuralink, Preserving Endangered Foods. May 14, 2021, Part 2
What’s Behind The Blockchain-Based Art Boom?
From multi-million dollar art sales to short NBA video clips, non-fungible tokens have taken off as a way to license media in the digital realm. The blockchain-based tokens, which function as a certificate of ownership for purchasers, produce a dramatic amount of carbon emissions and aren’t actually new—but in the first quarter of 2021, buyers spent $2 billion dollars purchasing NFTs on online marketplaces. Writers, musicians, and artists are all now experimenting with them, and big brands are also jumping on the bandwagon.
Ira talks to Decrypt Media editor-in-chief Dan Roberts, and LA-based artist Vakseen about the appeal, and how NFTs are bringing new audiences both to the blockchain economy, and artists themselves.
How Novel Is Neuralink?
Last month, the company Neuralink, co-founded by Elon Musk, released a video update of their technology. The company makes brain-computer interfaces, or BCIs—implants in the brain that detect signals and send them to a computer. In the video, a macaque named Pager sits in front of a screen, while a narrator explains Pager had two Neuralinks implanted in both sides of his brain six weeks before.
Pager is playing Pong. Not with a joystick or controller, but with his brain, according to the narrator. As with any Elon Musk venture, this Neuralink video got a lot of buzz. But brain-computer interfaces themselves are not a new concept. Where does this fit into the realm of neurotechnology research?
Joining Ira to talk about this Neuralink update is Dr. Paul Nuyujukian, director of Stanford University’s Brain Interfacing Laboratory in Palo Alto, California. Ira also turns to Nathan Copeland, a neurotechnology consultant and brain-computer interface participant in Pittsburgh, Pennsylvania. Six years ago, Copeland had four BCI devices implanted, and is one of just a handful of people to have BCI implants in his brain.
Decolonizing And Diversifying The Future Of Food
The Science Friday Book Club has been talking about food all spring while reading Lost Feast: Culinary Extinction and the Future of Food. We discussed the impacts of meat consumption, the extinction of beloved birds and plants, and the declining variety of fruit and vegetable varieties available in stores—and even about the flow of pollinator-produced crops in global food systems.
Producer Christie Taylor shares highlights from our off-radio Zoom event series, which asked, “What is the future of food, and who can help influence it for the better?”
At this April 20th panel, Lost Feast author and food geographer Lenore Newman joined farmer and former chef Mimi Edelman to talk about the future of food and flavor—from preserving heirloom seeds to the stories behind beloved flavors, and how policy changes and individual actions might contribute to a sustainable future.
At this May 4th panel, food researchers Katie Kamelamela, Noa Kekuewa Lincoln, and Melissa K. Nelson talked about their work researching and restoring Indigenous foods to Hawaii and the mainland United States. They explained how these foods were disrupted by colonization, and how food relationships fit into a future vision of sustainable food worldwide.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

May 14, 2021 • 47min
New Mask Rules, Pain Algorithm, Assorted Nuts, Muldrow Glacier. May 14, 2021, Part 1
Fully Vaccinated Can Unmask Often, CDC Says
As the number of vaccinated Americans continues to rise and evidence mounts that the vaccines may reduce viral transmission in addition to lessening disease severity, the CDC announced Thursday that fully-vaccinated people may be able to go mask-free except in specific crowded indoor situations. The announcement caused celebration in some circles and anxiety in others, with people wondering how the new guidelines fit into their personal risk assessments.
Sarah Zhang, staff writer at The Atlantic, joins Ira to talk about the latest news in the pandemic and beyond, including a WHO committee report discussing the early days of the outbreak, the latest on the Colonial gas pipeline shutdown, research into cats’ love of sitting in boxes, and more.
Can An Algorithm Explain Your Knee Pain?
In an ideal world, every visit to the doctor would go something like this: You’d explain what brought you in that day, like some unexplained knee pain. Your physician would listen carefully, run some tests, and voila—the cause of the issue would be revealed, and appropriate treatment prescribed.
Unfortunately, that’s not always the result. Maybe a doctor doesn’t listen closely to your concerns, or you don’t quite know how to describe your pain. Or, despite feeling certain that something is wrong with your knee, tests turn up nothing.
A new algorithm shows promise in reducing these types of frustrating interactions. In a new paper published in Nature, researchers trained an algorithm to identify factors often missed by x-ray technicians and doctors. They suggest it could lead to more satisfying diagnoses for patients of color.
Dr. Ziad Obermeyer, associate professor of Health Policy and Management at the University of California, Berkley joins Ira to describe how the algorithm works, and to explain the research being done at the intersection of machine learning and healthcare.
Ever Wonder Why Big Cereal Chunks Are Always On Top?
You may not have heard of it, but you’ve probably seen the “brazil nut effect” in action—it’s the name for the phenomenon that brings larger nuts or cereal chunks to the top of a container, leaving tinier portions at the bottom of the mix. But the process by which granular materials mix is weirdly hard to study, because it’s difficult to see what’s going on away from the visible surfaces of a container.
In recent work published in the journal Scientific Reports, researchers turn the power of three-dimensional time-lapse x-ray computer tomography onto the problem. By using a series of CT scans on a mixed box of nuts as it sorted itself by size, the researchers were able to capture a movie of the process—finally showing how the large Brazil nuts turn as they are forced up to the top of the mix by smaller peanuts percolating downwards.
Parmesh Gajjar, a research associate in the Henry Moseley X-ray Imaging Facility at the University of Manchester, talks with SciFri’s Charles Bergquist about the imaging study, and the importance of size segregation in mixing of materials—with applications from the formation of avalanches to designing drug delivery systems.
This Alaskan Glacier Is Moving 100 Times Faster Than Usual
One of the glaciers on Alaska’s Denali mountain has started to “surge.” The Muldrow Glacier is moving 10-100 times faster than usual, which is about three feet per hour. About 1% of glaciers “surge,” which are short periods where glaciers advance quickly.
Geologist Chad Hults has been on the glacier to study it during this surge period. He talks about how the glacier’s geometry and hydrology contribute to this surge period.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

May 7, 2021 • 48min
Beetles, Wildfires, Woodchip Bioreactor. May 7, 2021, Part 2
A Beetle’s Chemical (And Plastic) Romance
For many species of beetle, the key to finding a mate is scent: Both females and males give off pheromones that signal their species, their sex, and even their maturity level. How do researchers know? In experiments with dead beetles that have been sprayed with female pheromones, live males reliably attempt to mate with the dead insects.
But when one team of researchers based at the Chinese Academy of Sciences in Beijing and Syracuse University in New York tried to investigate whether this was true for the flea beetle Altica flagariae, they got a strange result. Males seemed confused when presented with scented dead beetles, leaving the team wondering if the dead beetles were still exuding their original chemicals. What is a research team to do? They attempted the same experiment, but with 3D-printed replicas. This time, the male beetles seemed clearly attracted to the female scent, the researchers wrote in the journal Chemoecology last month.
Producer Christie Taylor talks to Syracuse University biologist Kari Segraves about the intricacies of studying beetle intimacy, and the implications for evolutionary biology.
Nature’s Early Warning Signs For A Bad Wildfire Season
Last year, California saw a record breaking wildfire season. Nearly 10,000 fires burned over four million acres in the state.
Now, wildfire researcher Craig Clements is investigating natural indicators, like the chamise plant, for clues to predict what this wildfire season might look like. Normally, the wildfire season peaks during the late summer. This year, he’s observed a lower moisture content in these plants, possibly indicating the fire season may begin earlier.
Clements joins SciFri to explain how landscape, temperatures, drought, and atmospheric conditions all play a role in wildfire risk.
Arctic Wildfires Are Burning An Important Carbon Sink
California wildfires have made national headlines for the last several years, but important—and large—wildfires have also been burning in the forests above the U.S. Canadian border and near the Arctic circle.
A group of researchers wanted to know how these fires affected the northern forests and how this impacted their ability to store carbon. Their results were recently published in the journal Nature Climate Change. Jonathan Wang, an author on that study, discusses what this might mean for future climate change predictions.
Can Woodchips Help The Gulf Of Mexico’s Dead Zone?
In the Gulf of Mexico is an ecological dead zone, caused by algal blooms at the mouth of the Mississippi River. Warmer ocean temperatures provide the perfect conditions for algae to grow out of control, suffocating seagrass beds and killing fish, dolphins, and manatees. Fueling this toxic algae’s growth is nitrogen. The Mississippi river empties into the gulf, and drainage water from farms along it carries fertilizer ingredients—straight into the marine ecosystem.
While farmers have tried using practices to reduce fertilizer runoff, like cover crops, no-till farming and conservation buffers, for decades, the problem has only gotten worse. According to a new paper published in the journal Transactions of the American Society of Agricultural and Biological Engineers, a creative new approach involves denitrifying bioreactors—a system that allows bacteria to help convert nitrate in the water to harmless dinitrogen gas.
“It’s a complicated name, but it’s really a very simple idea,” says Laura Christianson, assistant professor of crop sciences at the University of Illinois at Urbana Champaign, and lead author on the study. She talks with SciFri producer Katie Feather about how a simple system involving woodchips in a trench can help keep nitrogen out of drainage water from farms across the midwest. Katie also speaks to Shirley Johnson, a farm-owner from Peoria, Illinois, about why she adopted the bioreactor technology, and what farmers can do to help their downstream neighbors.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

May 7, 2021 • 47min
Herd Immunity, Crossword Program. May 7, 2021, Part 1
Weighing COVID-19 Vaccinations For Teens
Federal officials are reporting that the Food and Drug Administration is poised to authorize Pfizer’s COVID-19 vaccine for children ages 12 to 15 by early next week—just as Canada became the first country to do so on Wednesday of this week. Pfizer has said they will seek out emergency authorization for even younger kids by the fall. But as most countries still lag far behind the United States in vaccine access for adults, public health officials are questioning the ethics of prioritizing American teens over adults from other countries.
Science writer Maggie Koerth joins Ira with more on the accessibility of COVID-19 vaccines for children, new projections of rapid sea level rise under climate change, and other stories from the week.
Is COVID-19 Herd Immunity Even Possible Anymore?
Since the start of the pandemic, we’ve equated getting out of this mess with the concept of herd immunity—when a certain percentage of the population is immune to a disease, mostly through vaccination.
With COVID-19, experts have said we need somewhere around 70 to 90% of the population to be immunized to meet this goal. Now that all adults in the U.S. are eligible for the vaccine, how far are we from that goal? And what is our trajectory?
Some experts now say with variants and vaccine hesitancy, herd immunity may not be possible here in the U.S. Joining Ira to break down this and other coronavirus quandaries is Angela Rasmussen, research scientist at VIDO-InterVac, the University of Saskatchewan’s vaccine research institute in Saskatoon, Saskatchewan.
This Computer Won The 2021 American Crossword Puzzle Tournament
In 2012, a computer program named Dr. Fill placed 141st out of some 660 entries in that year’s American Crossword Puzzle Tournament, a competition for elite crossword puzzle solvers. This year, the algorithm beat the human competition, completing the final playoff puzzle in just 49 seconds.
The A.I. relies on a collection of different techniques to make sense of a puzzle. Sometimes, a simple fact is needed—who was the First Lady before Eleanor Roosevelt? (Lou Henry Hoover.) More often, however, crossword puzzle solutions rely not just on factual knowledge, but an ability to recognize themes that puzzle constructors have embedded in the crosswords, along with an understanding of puns, homonyms, and word play. (Think: Five letters, “dining table leaves”—SALAD!) The program makes a series of statistical calculations about likely answers, then tries to fit those possibilities into the puzzle squares.
This year, researchers from the Berkeley Natural Language Processing group added their expertise to Dr. Fill’s algorithms—a contribution that may have helped push Dr. Fill to its crowning victory.
But the program isn’t infallible. This year, it made three mistakes solving puzzles during the tournament, while some human solvers completed the puzzles perfectly. It can make these errors with any unique puzzle form it’s never seen before.
Matt Ginsberg, the computer programmer behind Dr. Fill, joins Ira to talk about the competition and the advances his program has made over the years.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Apr 30, 2021 • 47min
Viking Metal, Possible Futures, Global Pollination. April 30, 2021, Part 2
Uncovering Metal Crafts Of The Viking Age
Vikings are often associated with scenes of boats and fiercely-pitched battles. But new research, published in the journal Archaeological and Anthropological Sciences, shows they also had other, calmer skills. The paper details advances in the cast metalwork of objects, such as keys and ornamental brooches, that occurred in the trading city of Ribe, Denmark in the 8th and 9th century.
Researchers analyzed samples of metal taken from a variety of metal objects found in Ribe, along with metalworking tools, crucibles, molds, and samples of metal slag. They found that while the Vikings began working in brass with a very experimental approach, they quickly standardized their production to use specific blends and alloys of metals. They also adopted more heat-resistant clays for crucibles, and made extensive use of recycling throughout their work processes.
Vana Orfanou, an European Research Commission (ERC) postdoctoral research scientist In the School of Archaeology at University College, Dublin, and lead author on the paper, joins SciFri’s Charles Bergquist to discuss the state of the art in early Scandinavian brass making.
An Illustrated Exploration Of Hypothetical Futures
Futurist and Flash Forward host Rose Eveleth spends her time asking a lot of ‘what if’ questions, and then exploring the answers with experts. For example, what if human light sources forever drowned out our dark night sky? What if we relocated endangered species to save them from climate change? What if, as she asked in 2018, we saw a deadly pandemic consume the globe?
With a new book that illustrates even more hypothetical futures, she poses even more far-reaching questions: What if we could change our gender like our hair color? What if we could live on as robots after our death? What if we had to pirate the basic pharmaceuticals, like insulin, that keep so many alive?
Eveleth sits down with SciFri’s John Dankosky to explore the nuances of imagining possible futures, whose choices influence what may actually happen, and why this work matters, even when she gets it wrong. Plus, what was predictable—and what was not—about the COVID-19 pandemic.
The Global Pollinating Forces Behind Your Food
Importing food from one country to another also means importing the resources that went into growing that food: Nutrients. Water. Sunlight. Human labor. And the labor of the bees, butterflies, or other insects and animals that provide pollination in that country’s ecosystems. Take Brazil, for example—Europe and the United States consume a large proportion of the country’s pollinator-dependent crops, from soybeans to mangoes, avocados, and other fruits.
Writing in the scientific journal Science Advances in March, an interdisciplinary team of Brazilian researchers describe a way to quantify and visualize this flow of pollinator effort, from one country to another. They created an interactive web tool that lets anyone see this pollinator flow, for a specific country or a group of countries.
Importantly, the researchers say, the model makes it clear that this flow occurs mostly from poor countries to rich ones—with economic and ecological consequences for the poorer countries. Farmers, for example, may clear more land to grow crops for export, removing valuable pollinator habitat in the process. Those same farmers might then see their yields drop as pollinators die off, thanks to loss of habitat.
Producer Christie Taylor talks to two members of the research team, economist Felipe Deodato da Silva e Silva, and ecologist Luisa Carvalheiro, about the importance of considering pollinators in global food trade, and how better informed policy and consumer choices might help preserve threatened biodiversity.
This segment is part of our spring SciFri Book Club. For another culinary exploration, join us in reading Lenore Newman’s Lost Feast: Culinary Extinction and the Future of Food.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Apr 30, 2021 • 47min
The Past And Future Of Plastics Tech. April 30, 2021, Part 1
The Future Of Plastics
Plastics do a lot of good. They’re sturdy, they’re clean, and the COVID-19 pandemic has really highlighted their benefits, with personal protective equipment like disposable gloves and masks.
But its durability is also its biggest problem. We’ve all seen photos of piles of plastic trash washed up on beaches, and animals surrounded by plastic bags and straws. Those materials will take decades, if not centuries, to break down. Even as it breaks apart, it can become millions of microplastic particles that cause their own problems.
So how do we tackle one of the biggest environmental crises of our time? Scientists are working on both ends of the plastic life cycle to come up with solutions. Breaking down the plastic that’s already out there, and coming up with alternative materials that could be better for the planet.
Guest host John Dankosky interviews two scientists doing great work on this topic: Dr. Francesca Kerton, professor of chemistry at Memorial University of Newfoundland in St. John’s, Canada, works on alternative polymers that could replace some plastics. Her latest research is focused on a polymer made from fishery waste. She’s joined by Dr. Gregg Beckham, senior research fellow at the National Renewable Energy Laboratory in Golden, Colorado, who works on enzymes that can break down plastics to its smaller building blocks for easier recycling.
Ask An Expert: What The Heck Are Microplastics?
Despite their small-sounding name, microplastics are a big deal. That’s because these tiny pieces of plastic debris can wind up just about anywhere. In fact, we know microplastics are in our oceans and our soil, and they can also get into what we eat and what we drink.
Since this is a relatively new problem, we don’t have a lot of long-term research on their effects. But investigations studying microplastics have already influenced legislation, and prompted innovations for combating plastic pollution.
Dr. Imogen Napper, a postdoctoral research fellow at the University of Plymouth in the United Kingdom, studied microbeads in facial scrubs. Her work led to a microbead ban in the United States and other countries. She says we need to rethink how we use plastic in our everyday lives for the health of the planet.
“It’s a fantastic material that’s so durable,” Napper tells Science Friday. “But we don’t need to make so many single-use applications that could last a lifetime,” especially when these products are only used briefly.
Napper and host John Dankosky talk about all the strange places microplastics have been found, and what role individual consumers play in combating an issue that can seem insurmountable. This conversation was held in front of a live Zoom audience.
Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.


