Pittsburgh’s Bridge Collapse Spotlights America’s Infrastructure Woes Our modern world is made up of infrastructure: Roads, buildings, and bridges all play a big role for many people’s daily lives. If these structures do their jobs well, we don’t think much about them. That is, until infrastructure fails. Bridge collapses are especially scary, like the structural failure in Pittsburgh, Pennsylvania last month. These events are shocking, and cause people to wonder how this could be allowed to happen. But looking at the numbers, it’s actually surprising there aren’t more failures. According to the American Road and Transportation Builders Association, a third of bridges in America are in need of repairs or replacement. Moreover, seven percent of the nation’s bridges are considered “structurally deficient.” And the problem could accelerate: Larger vehicles, more traffic, and climate change put a greater strain on bridges that already need regular maintenance. Joining guest host John Dankosky to talk about the engineering jargon around bridge infrastructure and new ways of building more resilient structures is Abbie Liel, professor of civil, environmental and architectural engineering at the University of Colorado in Boulder.   Why Did Ancient Ferocious Cat-Like Creatures Go Extinct? Can you imagine a world without cats? No furry loafs adorning our sofa arms. And no bobcats, mountain lions or jaguars either. Before there were cats in North America, there were nimravids, also known as “false” saber-toothed cats (while they had elongated canines, they weren’t actually cats). About 35 million years ago, nimravids roamed all over North America. But after 12 million years of dominating the continent, nimravids disappeared. For roughly the next 6.5 million years, there were no feline-like creatures anywhere in North America. This time period is called the Cat Gap. But why did nimravids go extinct? Guest host John Dankosky is joined by Chelsea Whyte, assistant news editor at New Scientist, who’s based in Portland Oregon, to discuss her reporting on this feline-less era.   Why Are Mice The Most Frequently Used Lab Animal? Mice and rats make up nearly 99% of animals used in research. But how did medical research come to be so dependent on these tiny rodents? How exactly do scientists genetically engineer mice to be suitable to study pretty much any human ailment? And why do the majority of medicines that are effective in mice fail in humans? Dr. Nadia Rosenthal, scientific director and professor at the Jackson Laboratory for Mammalian Genetics, based in Bar Harbor, Maine, talks with guest host John Dankosky to answer these questions, and more.   The Science Behind ‘Power Of The Dog’ When you think about science in films, you might think about space missions, disaster flicks, or techie thrillers, but probably not westerns. But Jane Campion’s film The Power of the Dog, a period drama about ranchers in Montana, turns on an interesting science twist. It is also widely considered a frontrunner to win an Oscar or three—it’s been nominated in several categories, including Best Picture. Benedict Cumberbatch plays Phil, an unlikeable rancher, whose world is disrupted when his brother marries a recent widow (played by Kirsten Dunst) and brings her son Peter (played by Kodi Smit-McPhee) into the home. The film doesn’t have a lot of dialogue. It’s a slow-boiling story about depression, psychological distress, alcoholism, masculinity, and sexuality. But (SPOILER ALERT!) it is also a story about anthrax, and the way in which Peter leads Phil to infect himself with the deadly agricultural disease by providing him with a hide from a downed cow. Sonia Epstein, executive editor and associate curator of science and film at the Museum of the Moving Image, based in New York City, joins John Dankosky to discuss the film and the medical mystery embedded in a landscape of mountains, cattle, and simmering emotions.   Blast Off To The Red Planet With The Spring Book Club The spring Book Club is setting sail for Mars! Join us as we read “The Sirens of Mars,” by planetary scientist Sarah Stewart Johnson, and discuss the search for life on our red planet neighbor. Radio producer and Book Club crew member Christie Taylor talks to guest host John Dankosky about the exciting scientific journey ahead for readers, with help from LibraryLinkNJ’s Stephanie Sendaula.   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.