The earth is facing a biodiversity crisis, and there’s a lot of attention on species that are threatened, or at risk of dying out completely. But, there’s another critter category that’s a little more mysterious: species that are “lost to science.” This means scientists aren’t quite sure how many of them there are out there—or if there are any left at all.

Producer Kathleen Davis talks to biologist Matt Forister, who is so dedicated to finding more information about these lost species that he created a whole scientific journal about them.

Plus, 28 of the 178 firefly species in the United States and Canada are currently lost to science, according to the community science project Firefly Atlas. We’re joined by firefly researcher Candace Fallon, who is working to confirm which firefly butts are still blinking and which have burnt out.

Want to help find fireflies near you? Find out how to participate in the Firefly Atlas.

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