Sönke Johnsen, a biologist at Duke University, specializes in ultra-black animals. He takes listeners on a journey into the science behind the darkest creatures on Earth, revealing how certain fish and butterflies achieve their deep black hues through unique structural adaptations. Johnsen discusses the fascinating interplay between darkness and bioluminescence, exploring survival strategies of deep-sea life. The conversation also touches on the implications of this research for engineering, merging biology with advancements in material science.