Fig. 3

a–c Blue feather of blue macaw and grey pigeon feather treated at 532 nm at a fluence of 0.5 J/cm² and 0.2 J/cm.². The white circle outlines the shape of the laser irradiated area; b–d SEM image of the feather barbules in the laser irradiated area. (The rows of white marks shown in a) delimit the area under investigation). © The Trustees of the British Museum. Shared under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) licence.