Ecology and Evolution of Animal Structural Color-Producing Materials

SémIdeev
 07/02/2025
 12:00:00
 Vinodkumar Saranathan, Chaire de Professeur Junior, Institut de Recherche sur la Biologie de l’Insecte (IRBI), UMR 7261 Centre National de la Recherche Scientifique / Université de Tours
 IDEEV - Salle Rosalind Franklin

Colors in animals can be produced either chemically by (usually diet-acquired, costly) pigments or physically by the constructive interference of light scattered by endogenous, cost-free, photonic nanostructures and sometimes as a combination of both. Fade-proof, saturated structural colors have evolved convergently in diverse animal taxa, including birds, insects and arachnids. However, given that the underlying nanostructures are overwhelmingly diverse in form and function, their characterization has suffered for over a century. I have pioneered the use of synchrotron Small Angle X-ray Scattering (SAXS) as a high throughput technique to structurally and optically characterize integumentary photonic nanostructures from hundreds of species across diverse animal orders in a comparative fashion. This led to the discovery of the first single gyroid crystals in biology within the iridescent green wing scales of certain papilionid and lycaenid butterflies, and recently in the feather barbs of the Blue-winged Leafbirds (likely driven by female preference for saturated hues). But broadly, this wealth of structural knowledge has led to the realization that these diverse photonic nanostructures share a unifying theme – they all appear to be self-assembled within cells by the co-option of fundamental intra-cellular processes: membrane invagination in insect scales and liquid-liquid phase separation in bird feather barb cells. In this talk, I will broadly summarize our current state of knowledge about the structure, function, development and evolution of self-assembled animal structural colors using examples from birds, butterflies, beetles, bees and tarantulas, including in the fossil record.

Illustration : Image au microscope à fluorescence super résolution d’une écaille d’aile de papillon en développement

Biography:

Dr. Vinodkumar Saranathan is a CNRS Junior Chair Professor at the Research Institute for the Biology of Insects (IRBI), where he studies the biomimicry of self-assembled photonic nanostructures in iridescent insect scales. His interdisciplinary research has been published in leading journals including PNAS, Advanced Materials, Nano Letters, Small, Cell Reports, Proceedings of the Royal Society B and his research has been featured in prominent international print (Quanta Magazine, New York Times, LA Times, Atlantic Monthly, Hindu Business Line, Times of India, etc.) and broadcast news media (BBC, CBC, NPR, Channel News Asia, etc.). Vinod received a bachelor’s degree in Physics with a minor in Philosophy cum laude from Ohio Wesleyan University. Funded by a Dillon and Mary Ripley Graduate Fellowship, he earned a Master’s in 2007 and a PhD in 2011 from the Department of Ecology and Evolutionary Biology at Yale University. Subsequently, Vinod was a Royal Society Newton Fellow at the Edward Grey Institute of Field Ornithology, Department of Zoology, University of Oxford. While at Oxford, he was also elected to an Edward P. Abraham Cephalosporin Junior Research Fellowship at Linacre College. Vinod was faculty at Yale-NUS College, and the Department of Biological Sciences at National University of Singapore (NUS), and an adjunct PI at the NUS Nanoscience and Nanotechnology Initiative (NUSNNI). Prior to joining IRBI, he was an Associate Professor of Biological Sciences at the Division of Science, within the School of Interwoven Arts and Sciences (SIAS) at Krea University, an elite 4-year liberal arts university in Southern India.