How many times has this happened to you? You’re standing in front of an open freezer, wondering what type of mystery meat has been left in there, when you purchased it, and if it’s still safe to eat? If you’re puzzled by sell-by dates, freezer burn, and just how long food can remain edible, you’re not alone. Studies show that more than 80 percent of Americans misinterpret date labels and throw food away prematurely to protect their families’ health. That adds up to $218 billion worth of food each year. Janell Goodwin, with the USDA’s Food Safety and Inspection Service, and Francisco Diez-Gonzales, professor and director of the Center for Food Safety at the University of Georgia, join Ira for a master class in food microbiology and safety. Then, Roni Neff of Johns Hopkins University Bloomberg School of Public Health explains how confusion over date labeling is worsening food waste and climate change.

Plus: A population of mole salamanders in the Midwest is throwing a curveball at our understanding of sex and reproduction. Some populations of this salamander are unisexual—they’re females that can reproduce without males. Katie Greenwald, an associate professor of biology at Eastern Michigan University, joins Ira to explain what advantages living a single-sex life may have for the mole salamander.

The herbicide glyphosate, found in products such as Roundup, has become a crucial tool on midwestern farms—but weeds are becoming resistant. What's next? Chris Walljasper, a reporter from the Midwest Center for Investigative Reporting, tells Ira more on the State Of Science.

And The Atlantic's Sarah Zhang tells us what's whipping up 2019's active tornado season in this week's News Roundup.

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Spoiler Alert, Glyphosate, Unisexual Salamanders. May 31, 2019, Part 1