Friday Harbor Marine Laboratories, University of Washington
San Juan Island, Washington
Archival Pigment Print
The clown nudibranch owes its bright spots of color to carotenoids—the pigments that also make carrots orange (carotene) and tomatoes red (lycopene). Carotenoids are widely touted for their human health benefits, and nutritionists advise eating carotenoid-rich foods because as animals, we can’t synthesize the compounds ourselves; They’re made only by plants, seaweeds, and other photosynthetic organisms. Similarly, the clown nudibranch must obtain the pigments from its food: the moss animals on which it feeds exclusively. The moss animals, in turn, get the compounds from the microscopic, photosynthetic organisms they eat. Another, more familiar animal that owes its spectacular color to carotenoids in its diet is the pink flamingo.