Thin section images of gekkotan eggshells.

Abstract

<p>A1–G1 were taken under plane-polarized light and A2–G2 cross-polarized light. White bars on the left side of the figures represent the boundary between the layers mentioned in the text and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0199496#pone.0199496.s001" target="_blank">S1 Text</a>. Outside of eggshell is up, consistent with <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0199496#pone.0199496.g003" target="_blank">Fig 3</a>. (A) <i>Gekko gecko</i>. White arrows point to the inner thick faint and outer thin dark bands, respectively. Black arrows mark the pore-like structures. (B) <i>Paroedura pictus</i>. White arrows point to the polygonal extinction patterns. Black arrows mark the location of ridge-like ornamentations. (C) <i>Paroedura stumpfii</i>. A white arrow in C1 marks a calcite concretion extending toward the interior of the eggshell. White arrows in C2 mark the triangular extinction pattern. (D) <i>Phelsuma grandis</i>. White arrows in D1 and D2 point a dark band and calcite granules, respectively. (E) <i>Correlophus ciliatus</i>. Extinction patterns are polygonal to triangular in shape (white arrows in E2). (F) <i>Rhacodactylus leachianus</i>. Extinction patterns are longitudinally thick, compared to those of <i>Correlophus ciliatus</i> eggshell (white arrows). The pore-like structure is marked by a black arrow. (G) <i>Eublepharis macularius</i>. Extinction pattern is not prominent, compared to other soft gekkotan eggshells but similar in shape (white arrows).</p