Songbirds Suffer Mystery Illness From The East Coast To The Midwest The reports started in late May: Songbirds in Washington, D.C. and neighboring regions were being found dead, often with swollen and crusty eyes. In the days that followed, similar sightings came from many states, including Kentucky, Virginia, Pennsylvania, and New Jersey. Now, the symptoms have been seen as far west as Indiana—but wildlife experts still aren’t sure what’s causing the deaths.  The illness has affected many species, including American robins, blue jays, common grackles, and European starlings. So far, investigators have found no signs of   salmonella and chlamydia; avian influenza virus; West Nile virus and other flaviviruses; Newcastle disease virus and other paramyxoviruses; herpesviruses and poxviruses; or Trichomonas parasites. But unfortunately, their tests have been inconclusive as to the actual cause. Experts are asking people in the affected areas to be on the lookout for birds with crusty eyes or behaving strangely—and in an effort at avian social distancing, they’re suggesting removing bird feeders until the cause of the ‘mortality event’ is known.  Ira talks with Allisyn Gillet, state ornithologist for Indiana, and Lisa Murphy, a toxicologist and co-director of the Wildlife Futures Program at the University of Pennsylvania School of Veterinary Medicine, about what’s known so far about the illness, and about what steps investigators are taking to try to solve the medical mystery.  If you find a bird exhibiting these symptoms, researchers encourage you to report it to the Wildlife Futures Program at the University of Pennsylvania.     Sweating Is Our Biological Superpower Sweat may feel like a constant summer companion, whether or not you exercise frequently. Being damp can feel uncomfortable, but the smells that follow—thanks to the lives and deaths of sweat-munching bacteria—are often socially stigmatized as well. (Deodorant itself is actually a very recent invention!) But sweat isn’t just a cosmetic embarrassment: It’s crucial to keeping us cool, as the evaporating liquid pulls heat energy from our bodies. If you look at animals that don’t sweat, many have evolved alternate adaptations like peeing or even pooping on body parts to achieve that vital evaporative effect. People who are born unable to sweat run a constant risk of heatstroke. Ira talks to Sarah Everts, author of the new book, The Joy Of Sweat, about what makes sweat useful, the cool chemistry of this bodily fluid, and why it’s our evolutionary superpower.      Betelgeuse’s False Supernova Alarm The famous red giant star, Betelgeuse, sits on the left shoulder of the constellation Orion. It’s one of the brightest stars in the night sky, distinguishable by its faint red hue.  In December 2019, the star suddenly dimmed to about a third of its usual brightness. Scientists called this the ‘Great Dimming.’ And there was some speculation in the news that the dimming meant Betelgeuse was about to explode in a giant supernova. But within months, Betelgeuse quietly returned to its original brightness, leaving astronomers perplexed. Now, nearly two years after the initial dimming, a study recently published in Nature proposed a theory for Betelgeuse’s Great Dimming. Supernova expert Sarafina Nance joins Ira to talk about Betelgeuse, give an outside perspective on the new Nature study, and discuss her science communication work.