The brightest hues in nature are produced by tiny patterns in, say, feathers or scales rather than pigments. These so-called “structural colours” are widespread, giving people their blue eyes, and peacocks their brilliant feathers.
For communication
Many animals use this type of colour for communication, notably butterflies and moths ( Lepidoptera ), which display the biggest range of structural colours and put them to uses from advertising their toxicity to choosing the best mates.
But despite the importance of structural colours in their lives, little is known about how lepidopterans developed these key social signals.
According to a paper in PLoS Biology , palaeobiologist Maria McNamara of Yale University and colleagues bring us closer to the origins of structural colours by reconstructing them in fossil moths that are 47 million years old.
This is the first evidence of structurally coloured scales in fossil lepidopterans . The fossil moths came from the Messel oil shale in Germany, a site famous for exquisite fossil preservation.