Humans accumulate porphyrins in the body mostly during the course of porphyrias, diseases caused by defects in the enzymes of the heme biosynthesis pathway and that produce acute attacks, skin lesions and liver cancer. In contrast, some wild mammals and birds are adapted to accumulate porphyrins without injurious consequences. This study proposes to view such physiological adaptations as potential solutions to human porphyrias, and suggest certain wild animals as models.

Porphyrins are pigments produced in most animal cells during the synthesis of heme, but their importance for external coloration is unclear. Owls are among the few animals that accumulate porphyrins in the integument, where it could serve as a means of signaling. Here authors hypothesized that the porphyrin content of feathers may depend on body condition and breeding site quality in Eurasian eagle owl fledglings.