Imagine, you're a toxic toad hanging around South America. No other animals are gonna mess with you, right? After all, if anyone tries to eat you, they'll be exposed to something called a cardiotonic steroid — and may die of a heart attack.
Well, unfortunately for at least cane toads, some other animals have developed adaptations to their toxic steroids.
Evolutionary biologist Shabnam Mohammadi has spent her career studying how these adaptations work — and says humans have used these toxins to their advantage since ancient Egypt.
"To this day, we still do that actually," Mohammadi says. "Some versions of cardiotonic steroids are prescribed for treating congestive heart failure."
Today on the show, we explore the uses for these toxins and talk to Mohammadi about the adaptations that allow some predators to consume cardiotonic steroids without getting sick.
Curious about biology? Email us at shortwave@npr.org.
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This episode was produced by Rachel Carlson, edited by Rebecca Ramirez and fact-checked by Tyler Jones. Kwesi Lee was the audio engineer.
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