Two topics were developed during this doctoral thesis : the hygrochromic phenomenon and the production of peculiar visual effects due to multiscale structures. Both subjects found their origin in the study of natural photonic structures, improved through Evolution. We first studied four coleoptera, which elytra changed color due to the humidity level of their environment. This hygrochromic phenomenon originated from structures which were unique to each insect. We then analyzed the peculiar coloration mechanism of four other insects. Their colors emerged from the interaction of the light with structures at different length scales. A computational code was implemented to modelize such interactions, based on the Monte-Carlo approach and on the ray-tracing method. It appeared clearly through these studies that there was a large diversity of structures in Nature which produced quite uncommon visual effects. This creativity compensated for the lack of available material to create the necessary contrast of refractive index. The state-of-the-art fabrication techniques allowed us to benefit from this creativity, with the advantage of having a much larger variety of materials available.