ISLAMABAD-Researchers from Yale-NUS College in Singapore and University College Cork (UCC) in Ireland have analyzed preserved scales from wing cases of two fossil weevils from the Late Pleistocene era (approx. 13,000 years ago) to better understand the origin of light-scattering nanostructures present in present-day insects. The researchers, led by Yale-NUS Assistant Professor of Science (Life Sciences) Vinod Kumar Saranathan and UCC paleobiologists Drs Luke McDonald and Maria McNamara, found that the wing cases of the fossil weevils contained preserved photonic ‘diamonds’, one of the many types of crystal like nanoscopic structure that interacts with light to produce some of the brightest and purest colors in nature.

The outer coverings of many insects comprise repeating units arranged in a crystalline formation that interact with visible light to produce structural colors, which typically have a metallic, iridescent appearance. For many of these insects, the iridescent colors perform a variety of functions including camouflage, signaling potential mates, and warning off predators. To date, the evolutionary history of these complex tissue structures has not been clearly defined. This study highlights the great potential of the fossil record as a means to unearth the evolutionary history of structural colors, not only in weevils but also in other insects, and paves the way for further research on the development of these light-scattering nanostructures and the vibrant colors they give rise to