Eye development patterns of the RPE. The terminals in the tree include only those species for which embryological data is available. The two alternative patterns of development of RPE were mapped onto a metatree of Squamata based on molecular hypotheses from four independent studies: Lacertidae ; Gekkota ; Squamata [90, 91]. Gray branches indicate species with the spherical RPE pattern, black branches ovoid → spherical RPE pattern. Asterisk indicates taxa not observed; orange branches indicate uncertain character state. Diagrams of the RPE at oviposition (O) and eclosion (E) were redrawn from published figures for those species (see text for references). Numbers on the cladogram correspond to the following taxonomic groups: 1-Squamata, 2-Scincidae, 3-Teiidae, 4-Gymnophthalmidae, 5-Lacertidae, 6-Amphisbaenidae, 7-Serpentes, 8-Anguidae, 9-Iguania, 10-Chamaeleonidae, 11-Iguanoidea, 12-Iguanidae, 13-Tropiduridae, 14-Polychrotidae, 15-Dactyloidae, 16-Gekkota, 17-Gekkonoidea, 18-Eublepharidae, 19-Phyllodactylidae, 20-Gekkonidae, 21-Sphaerodactylidae, 22-Sphaerodactylinae (sphaerodactyls). Inset, Sphaerodactylus macrolepis mimetes egg open to expose embryo (Stage 35).