Why Do Cats Purr? An Investigation Into A Purr-fect Mystery Science Friday recently received a voicemail from a listener named Violet from Maui, Hawai’i, who wanted to know: Why do cats purr? We wanted to see what other cat lovers knew about cat purring. So we sent our talented SciFri colleagues Diana Montano and Kyle Marian Viterbo to the Meow Parlor, a cat cafe in New York City to find out. Guest host Katherine Wu, who recently wrote about why cats purr for The Atlantic, also talks with Robert Eklund, professor of language, culture, and phonetics at Linköping University in Linköping, Sweden. He explains what we do and don’t know about how and why cats purr.   How To Digitally Recreate Darth Vader’s Voice From A War Zone James Earl Jones played Darth Vader for 45 years. But this September, he officially stepped down from the role. Fear not, Star Wars fans—the villain isn’t gone for good. Instead, the filmmakers have teamed up with the Ukrainian AI company Respeecher to recreate his voice. Respeecher can convert one person’s speech into the voice of another. The company’s work has appeared in the Star Wars canon already, as Young Luke Skywalker in “The Mandalorian” and “The Book of Boba Fett.” And just last month, they debuted their Darth Vader mimic in the T.V. show “Obi-Wan Kenobi.” They always knew that it would be challenging to recreate Vader’s iconic voice. But their job got a whole lot harder when Russian troops invaded their nation. Respeecher chief technology officer Dmytro Bielievtsov and sound engineer Bogdan Belyaev join guest host Kathleen Davis to talk about their work.   Toxic Death Cap Mushrooms Take Root In The Mountain West Toxic mushrooms are not unusual in the Mountain West. “This is probably a lepiota,” said Susan Stacy, looking at a mushroom on a recent afternoon in a Boise, Idaho, neighborhood not far from downtown. “See that little dark nub in the middle and little flecks around here?” Stacy turned to her mushroom identification book. “Edibility: to be avoided. Perhaps poisonous,” she said. While this little mushroom could be problematic for a curious dog or child, it doesn’t compare to one of the world’s deadliest mushrooms – which Stacy discovered in Boise last September. She remembers that it was a hot day, and she decided to take a detour from her normal route to check out a busier area where many lawns were “generously” watered. “And here I come upon this mushroom, and I knew it was an Amanita because I had seen them before. And an Amanita, to my mind, is a gorgeous, statuesque, elegant creation. They’re just stately,” she said. The genus Amanita includes, incidentally, the species on which the red and white mushroom emoji is likely based, which also happens to be poisonous. Read the rest of this story on sciencefriday.com   Will A Hotter World Make Jellyfish Haute Cuisine? The ocean is filled with delicious ingredients, but our favorite seafood items might not stick around on menus forever … thanks to climate change taking its toll on fisheries. As a result, scientists are thinking more and more about what the future of food is going to look like—what ingredients we should eat more, and what we should eat less. That could mean we’ll eat more items like kelp, oysters, and mussels, which are a great source of nutrients, since they can be sustainably harvested. But there’s another seafood that’s being encouraged as a food of the future. But it’s a little more unfamiliar—and maybe surprising—to most of the world. It’s jellyfish. Although it’s a fairly common ingredient in several countries, like China and Vietnam, it hasn’t quite broken into the international market yet. Guest host Katherine Wu talks with Agostino Petroni, a journalist based in Rome who reported on the topic for Hakai Magazine, and Dr. Antonella Leone, a researcher at the Italian National Research Council’s Institute of Sciences of Food Production, based in Lecce, Italy. They talk about the benefits of jellyfishing, what it’s going to take to catapult jellyfish into the international seafood market, and their favorite jellyfish recipes.   Transcripts for each segment will be available the week after the show airs on sciencefriday.com.   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.