From red to white to orange to blue, fish flesh can land almost anywhere on the color spectrum.
What's behind this huge variation? A lot of things — from genetics to bile pigments. And parsing the rainbow can tell us something about where a fish came from, its swimming routine and what it ate.
Red yellowfin tuna: A classic of the sashimi counter, the yellowfin tuna is also the Michael Phelps of the fish world. And its athletic prowess has a lot to do with its ruby red flesh.