The jalapeño is the workhorse of hot peppers. They’re sold fresh, canned, pickled, in hot sauces, salsas, smoked into chipotles, and they outsell all other hot peppers in the United States. These everyday chilies are a scientific and sociological marvel, and tell a complicated story about Mexican food and American palates. In today’s episode, we meet Dallas-based food critic Brian Reinhart, who fell in love with spicy Mexican cuisine as a teenager. Recently, Brian started to notice that the jalapeños he’d buy in the grocery store were less and less hot. So he called up an expert: Dr. Stephanie Walker, who studies chili pepper genetics at New Mexico State University. She explains that the food industry has been breeding milder jalapeños for decades – a project led by “Dr. Pepper” himself, Benigno Villalon.  Finally, Los Angeles Times columnist Gustavo Arellano puts the jalapeño in context, as part of an age-old cycle in Americans’ obsession with Mexican food: one more ingredient that’s been “discovered,” celebrated, then domesticated. Brian Reinhart’s article about the jalapeño ran in D Magazine. Gustavo Arellano’s book is called Taco USA: How Mexican Food Conquered America.  This episode was produced by Evan Chung, who produces the show with Katie Shepherd and Max Freedman. Derek John is Executive Producer. Merritt Jacob is Senior Technical Director. If you haven’t yet, please subscribe and rate our feed in Apple Podcasts or wherever you get your podcasts. And even better, tell your friends. If you’re a fan of the show, please sign up for Slate Plus. Members get to listen to Decoder Ring and all other Slate podcasts without any ads and have total access to Slate’s website. Your support is also crucial to our work. Go to Slate.com/decoderplus to join Slate Plus today.  Learn more about your ad choices. Visit megaphone.fm/adchoices