The eyes and wings of some species of moth are covered in arrays of densely-packed pillars with heights and spacings of approximately 200 nm. These structures introduce a grading in the effective refractive index at the surface and so have an antireflective effect, allowing the moth to avoid detection by predators. This mechanism results in low reflectance for a broad range of wavelengths and angles of incidence, properties which would be highly beneficial to solar cells, where the aim is to transmit as much of the incident solar spectrum through the surface and into the cell as possible. We are investigating ways to mimic moth-eye structures in silicon solar cell designs to form antireflective surfaces that are superior to traditional thin film coatings.