Most of us land-lubbers assume that light-making among ocean creatures is an exotic and rare phenomenon. But that’s wrong. The majority of animals in the ocean, which means the majority of animals on the planet, are capable of making light. From top to bottom, the ocean is teeming with unforgettably beautiful and extraordinarily diverse light shows made by animals that we’re only beginning to understand, from deep-sea shrimp that distract predators by spewing glowing mucus to squids that backlight their body tissue in flickering patterns that seem to coordinate group hunting. In this episode, we speak with Dr. Edie Widder, a renowned deep sea explorer and world authority on marine bioluminescence, about ocean animals’ language of light, her startling beautiful experiences in the deep, how dim our understanding of much of the ocean still is, and why investing in ocean exploration is key to ocean protection.