Extended Data Fig. 3: EBSD analysis of calcified crane-fly ommatidial lenses.
From: Fossil insect eyes shed light on trilobite optics and the arthropod pigment screen
a, Compound eye of specimen FUM-N-13923, indicating analysed section (horizontal white line). b, Semi-transparent ommatidial lenses and darkly pigmented corneal facet walls shown in oblique section. c, FEG-SEM micrograph of the fossilized cornea. d, e, Enlargements of the boxed areas in c. Dashed coloured lines delineate individual ommatidial lenses analysed with EBSD (d, e, n = 15 separate lenses). Pole figures (stereographic projection, upper hemisphere) illustrate the {0001} (c-axis) orientation of six representative calcite crystals. Note that the c-axis is aligned with the optical axis in all lenses (yellow asterisk denotes the fossil lens depicted in Fig. 2c). Scale bars, 200 μm (b, c), 300 μm (a).
