Science Friday Folgen

What Went Wrong With Jackson, Mississippi’s Water? Residents of Jackson, Mississippi have been dealing with a water crisis since a storm rolled through town on February 15th. The city’s water system was damaged, leaving thousands of residents without running water at home. People have relied on water distribution sites to get by, and even those who can still use their taps are on boil water notice. Impacted residents are largely low-income, and the limited access to water has raised worries about staying safe during the COVID-19 pandemic. Even before this fiasco, Jackson’s water system was in need of a change. Boil water advisories were common, and many of the city’s pipes date back to the 1950s. Water service is expected to be restored this week, but getting the taps running again will just be a Band-Aid: A true overhaul would require millions, if not billions of dollars. Mississippi Public Broadcasting reporter Kobee Vance joins guest host John Dankosky to discuss what’s happening in Jackson, and why its infrastructure was particularly vulnerable to this crisis.   Spinning Glass To See The Stars Last weekend, a giant furnace built under the east stands of the University of Arizona football stadium began to spin. That furnace contained some 20 tons of high-purity borosilicate glass, heated to 1,165 degrees C. As the glass melted, it flowed into gaps in a mold. The centrifugal force of the spinning furnace spread the material up the edges of the mold, forming the curved surface of a huge mirror, with a diameter of 8.4 meters. The piece is just one of seven sections that will eventually form the 25-meter primary mirror of the Giant Magellan Telescope in Chile. It’s not a fast process—it will take several months to cool, and then another two years to measure, grind, and polish. When that’s complete, the surface of the mirror segment will be accurate to within twenty-five nanometers. Steward Observatory mirror polishing program project scientist Buddy Martin says that when it’s complete, the Giant Magellan Telescope should be ten times sharper than the Hubble Space Telescope—if it was positioned in Washington, DC, it would be able to make out a softball in the hand of a pitcher in San Francisco. Martin talks with SciFri’s Charles Bergquist about the mirror production process, and the challenges of working with glass on massive scales. Watch a video and see photos of the process at scienefriday.com.   It’s Time To Rethink Shark Sex—With Females In Mind Sharks, rays, and skates—all fish in the subclass Elasmobranchii—are a beautifully diverse collection of animals. One big way they differ is in how they reproduce. They lay eggs, like traditional fish, and let them mature in a select corner of the ocean. Or, they might let the eggs hatch inside their bodies. But they can also give live birth to pups gestated like mammals: with an umbilical cord and a placenta in a uterus. It doesn’t end there. These fish, like many other members of the animal kingdom, have two uteruses. Females are capable of reproducing asexually, without help from a male. As genetic sequencing has advanced, researchers have been finding another curious pattern: Many litters of pups will have more than one father, a phenomenon known as multiple paternity. Evolutionary ecologists seeking to explain why sharks would use this strategy of multiple paternity have hypothesized it’s one of convenience for females. In species with aggressive and competitive mating practices, like many sharks and rays, it’s possible females find it saves them precious resources to acquiesce to multiple males. But what if there’s something in it for the female, and her likelihood of having successful, biologically fit offspring? That’s the question a team of researchers sought to answer in new research published in Molecular Ecology this month, where they asked what kinds of physiological mechanisms a female shark or ray might use to wield agency in her own reproduction. The researchers also write that a male-dominated field may be more likely to miss a female-driven reproductive strategy, and push for more study of female reproductive biology. John Dankosky talks to the lead author on the research, Georgia Aquarium shark biologist Kady Lyons, about the vast wonderland of reproductive strategies in this fish subclass—and what a history of male-centered research may have missed.   What Next For The Fully Vaccinated? In the U.S., vaccines have been rolling out since December. According to the Centers for Disease Control and Prevention, more than 95 million doses have been administered which equates to over 18% of the population. This week, the agency also put out guidelines for those who have been fully vaccinated. Sophie Bushwick of Scientific American fills us in on those guidelines and also talks about research on the effectiveness of mask mandates and a headless sea slug.     Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

When Is It Time To Say Goodbye? Imagine you’re having a conversation with someone. You may get the sense that they have somewhere else to be. Or you might start feeling restless, and use an excuse to cut the conversation short. Sometimes, you feel like you could talk for HOURS. Chances are you’re wrong every time.  In a study published this week in the Proceedings of the National Academy of Sciences, Adam Mastroianni and colleagues tried to figure out how good humans are at judging the ideal length of a conversation. They found that both participants agreed a conversation ended at the right time in only 2% of their trials. And the difference between one partner’s desired conversation length and the actual length of a conversation could be as much as 50%—so in a 10 minute conversation, your partner might have wanted to talk to you for as little as 5 minutes, or as much as 15 minutes. SciFri’s Charles Bergquist talks with Mastroianni about these results, and why the “exit ramps” to a conversation are rarely where you want them to be. Talking Through The History Of Our Teeth Most of us have never thought much about why we have teeth. But if you’re the parent of a teething infant, the question becomes a whole lot more relevant: While you impatiently wait for baby’s teeth to poke through, or soothe your teething toddler in the middle of the night, you might find yourself wondering why humans go through all this trouble for a set of teeth that are only temporary. In a decade, your child will have shed their baby teeth to make room for their adult counterparts, and all this fuss will be but a distant—albeit painful—memory for both you and your former infant. But one such question can lead to another. Are baby and adult teeth made of the same stuff? Why can’t we just grow a new tooth if we lose one? And how did ancient people take care of their teeth? Biological anthropologist and ancient tooth expert Shara Bailey joins Ira to discuss why our teeth are the way they are.  A Look Back At The Time Of The Tasmanian Tiger Last week, conservation biologists on Twitter were all aflutter as rumors circulated that a creature called a “thylacine,” better known as a “Tasmanian tiger,” had been caught on camera in the Tasmanian bush. Thylacines have been considered extinct since the mid 80’s, but there are still those who believe—or hope—they still exist.  In a video posted to YouTube, Neil Waters, President of the Thylacine Awareness Group of Australia, shared the news of what he thought looked like images of two adult thylacines and a baby. Unfortunately, this time the animal caught on camera was identified as a pademelon. But at Science Friday, we’ll never pass up an opportunity to celebrate a charismatic creature. Last January, SciFri’s Elah Feder spoke with Neil Waters and Gregory Berns, a psychology professor at Emory University, about the fascinating history of the Tasmanian tiger.  Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Oregon Just Decriminalized Small Amounts of All Drugs. Now What? On February 1, a big experiment began in Oregon: The state has decriminalized small amounts of all drugs, including heroin, cocaine, and methamphetamine. In the November election, voters passed ballot Measure 110 by a 16-point margin. Now, if you’re caught with one or two grams of what some refer to as “hard drugs”, you won’t be charged. Instead, you’ll either pay a maximum $100 dollar fine, or complete a health assessment within 45 days at an addiction recovery center. This new system for services will be funded through the state’s marijuana tax. But the measure is still controversial, and members of Oregon’s addiction and recovery community are split on if it’s a good idea. So how did we get here? Read and listen to the full story here.     Wisconsin Oversteps in Wolf Hunt One of the final acts of the Trump Administration in late 2020 was to remove the gray wolf from the federal endangered species list. The U.S. Fish and Wildlife Service officially removed the species, which was once nearly extinct in the lower 48 states, in January. The wolves now number more than 6,000 in the northern Rockies and the western Great Lakes states. In Wisconsin, a 2012 state law requires an annual wolf hunt when the animals are not under federal protection. State wildlife officials had begun planning for a hunt next November, but were forced by a lawsuit from an out-of-state hunting group to hold one before the end of February. That hunt lasted only three days before state officials shut it down: Licensed hunters killed 216 wolves in that time, more than 80 percent over the allowed quota of 119, and nearly 20 percent of the state’s estimated 1,000-plus wolves. SciFri producer Christie Taylor talks to Wisconsin Public Radio reporter Danielle Kaeding and environmental science professor Adrian Treves about how hunters were able to kill so many wolves so fast—and what effect this year’s hunt might have on the health of wolf populations in the state.   What Does Johnson & Johnson’s Shot Mean for Our Vaccine Timeline? The U.S. now has a third COVID-19 vaccine in our arsenal, as Johnson & Johnson’s shot got emergency approval last weekend. This one is different from the Pfizer and Moderna vaccines already in use: It’s only one dose, it’s inexpensive, and it doesn’t require very cold temperatures for storage. This means rural communities might get vaccinated faster, and our timeline to possible COVID-19 herd immunity could improve. Scaling up vaccinations will be critical as the homegrown U.S. COVID-19 variants are taking hold. Variants from California and New York are becoming more widespread, though it doesn’t seem like we’ll need to change our strategy for fighting COVID-19 yet. Ira is joined by Umair Irfan, staff writer at Vox, to talk about these stories and other big science news of the week.     Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.