Elucidation of the chemical composition of avian melanin

Our understanding of the chemical composition of melanin remains limited, due to a paucity of direct measurements. Avian feathers have an unparalleled diversity of melanin-based color mirroring their complex chemistry. Synchrotron-based photoionization mass spectrometry is used to determine the chemical composition of melanin from samples of black, brown, grey and iridescent feathers.