Science Friday Folgen

If you stood in southeastern Utah over 200 million years ago, you’d be overlooking the ocean. The landlocked state wasn’t quite the same landscape of scarlet plateaus and canyons you might see today, but a coastal desert where sand dunes butted up right against the sea. And it was home to some of the earliest dinosaurs. In this region of Utah, today known as Indian Creek in Bears Ears National Monument, the remains of dinosaur relatives, known as protodinosaurs or “dinosaur aunts and uncles,” are buried in the Earth. Their bones tell the stories about the dawn of dinosaurs, prehistoric Utah, and a much warmer Earth. In the northern reaches of Utah’s Great Salt Lake sits Gunnison Island, a narrow strip of land just a mile long and half a mile wide. Despite its small size, the island hosts the world’s second largest white pelican rookery, with an average of 20,000 birds and 6,000 nests. Biologist Jaimi Butler of Westminster College’s Great Salt Lake Institute calls the birds the “polar bears” of Great Salt Lake—because as lake waters drop, the birds’ island refuge is now threatened by humans, coyotes, and other predators. Butler and her team have installed cameras on the island, and citizen scientists can now use these “PELIcam” images to help Butler and her colleagues catalog the white pelican population on the island—and the appearance of predators, too. Forest ecologist Nalini Nadkarni pioneered the exploration of tree canopies—the “new frontiers” of the forest, using hot air balloons, rock climbing gear, and cranes. There, high in the trees, she found soil coating the branches, much like the soil on the forest floor—and unique adaptations, like the water-gathering abilities of spiky bromeliads. In this segment, recorded live at the Eccles Theater in Salt Lake City, Nadkarni takes Ira on a tour of the forest canopy, talks about how fashion can be a tool for science communication, and describes her work communicating science to underserved populations, like inmates in prisons around the nation—from minimum security to Supermax. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Since the 1980s, Gerta Keller, professor of paleontology and geology at Princeton, has been speaking out against an idea most of us take as scientific gospel: That a giant rock from space killed the dinosaurs. Nice story, she says—but it’s just not true. Gerta's been shouted down and ostracized at conferences, but in three decades, she hasn’t backed down. And now, things might finally be coming around for Gerta’s theory. But is she right? Did something else kill the dinosaurs? Or is she just too proud to admit she’s been wrong for 30 years? Subscribe to Undiscovered HERE, or wherever you get your podcasts. GUESTS Gerta Keller, professor of paleontology and geology at Princeton James Powell, geologist and author of Night Comes to the Cretaceous: Dinosaur Extinction and the Transformation of Modern Geology (St. Martin's Press) FOOTNOTES Michael Benton reviews the many, sometimes hilarious explanations for the (non-avian) dinosaurs’ extinction. Note: Ideas marked with asterisks were jokes! More in Benton’s book. Walter Alvarez tells his own story of the impact hypothesis in T. Rex and the Crater of Doom. The New York Times interviews Luis Alvarez before he dies, and he takes some parting shots at his scientific opponents. The impact and the Cretaceous-Tertiary boundary were simultaneous according to this paper. Learn more about how volcanoes are major suspects in mass extinctions. Read more about Gerta Keller, the holdout. CREDITS This episode of Undiscovered was reported and produced by Elah Feder and Annie Minoff. Our senior editor is Christopher Intagliata. Original music by Daniel Peterschmidt. Fact-checking help from Robin Palmer. Lucy Huang polled visitors to AMNH about what killed the dinosaurs. Our theme music is by I Am Robot And Proud. Excerpts from All Things Considered used with permission from NPR. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Climate change is increasing temperatures and causing heavier rainfalls across the country. Scientists are studying how these changes will affect different natural resources, including the soil ecosystem. For example, in Wisconsin, soil erosion is predicted to double by 2050 due to heavier rainfalls, according to a report by the Wisconsin Initiative on Climate Change Impacts. Agricultural scientist Andrea Basche talks about how soil formation and health is tied to climate. She joins microbiologist Kristen DeAngelis, who is conducting a long-term study to determine how increased temperatures affect soil microbiome, how to protect this resource, and what our soil reserves might look like in the next fifty years. Plants have a unique challenge in staying alive long enough to produce offspring. Unable to move and at the mercy of their surroundings, they present a tempting source of nutrition for bacteria and animals alike. But they’re not helpless. Botanists have long known plants are capable of sensing their environments and responding to them. They can grow differently in response to shade or drought, or release noxious chemicals to fend off predators, even as a caterpillar is mid-way through chewing on a leaf. But how does that information travel? New research published in the journal Science shows a first glimpse, in real time, of distress signals traveling from one leaf, snipped, crushed, or chewed, to other healthy leaves in the same plant. The signal, a wave of calcium ions, seems linked to the amino acid glutamate, which in animals acts as a neurotransmitter. University of Wisconsin-Madison botany professor Simon Gilroy, a co-author on the new research, explains this chemical signaling pathway and other advances in how we understand plant communication.  At some science fairs, baking soda volcanos can grab the blue ribbon prize. But at the International Science and Engineering Fair (ISEF), a winning project is a design to kill cancer cells. ISEF is the grand championship of science fairs, where students from around the world submit their best research projects and compete in a high-stakes, hormone-filled challenge, which is showcased in full display in the new film, Science Fair. Like any high school experience, it can be a pressure cooker of anxiety, but also a time when many students find their calling—a crucible from which our future scientists are born. Ira talks with one of the film’s directors, Cristina Costantini, and catches up with a former ISEF participant Robbie Barrat, to discuss life after Science Fair. View a trailer of the film below and find screening times and locations here. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.