DOI: 10.5061/dryad.rbnzs7hjc
title: A Morrison stem gekkotan reveals gecko evolution and Jurassic biogeography

description: Geckos are a speciose and globally distributed clade of Squamata (lizards,
 including snakes and amphisbaenians) that are characterized by a host of
 modifications for nocturnal, scansorial, and insectivorous ecologies. They
 are among the oldest divergences in the lizard crown, so understanding the
 origin of geckoes (Gekkota) is essential to understanding the origin of
 Squamata, the most species-rich extant tetrapod clade. However, the poor
 fossil record of gekkotans has obscured the sequence and timing of the
 assembly of their distinctive morphology. Here, we describe the first
 North American stem-gekkotan based on a three-dimensionally preserved
 skull from the Morrison Formation of western North America. Despite its
 Late Jurassic age, the new species already possesses several key
 characteristics of the gekkotan skull along with retained ancestral
 features. We show that this new stem gekkotan, and several previously
 named species of uncertain phylogenetic relationships, comprise a
 widespread clade of early crown lizards, substantiating faunal homogeneity
 in Laurasia during the Late Jurassic that extended across disparate
 ecological, body-size, and physiological classes.
description: # A Morrison stem gekkotan reveals gecko evolution and Jurassic
 biogeography This dataset
 contains 5 supplementary datasets to our article A Morrison stem gekkotan
 reveals gecko evolution and Jurassic biogeography. They are as follows.
 Set 1 contains our phylogenetic dataset, which is a modified version of
 the dataset of Gauthier et al., 2012. This dataset was assembled in
 Mesquite v 3.70. This file is labeled: "Supplmental File
 1-Helioscopos_Matrix.nex" Set 2 contains .tre files of the strict
 consensus trees of our maximum parsimony analyses of our dataset (both
 equal and implied weights and with and without a molecular constraint).
 These analyses were performed via new technology searches in TNT v 1.5.
 These files are named with the description of the paramaters used for each
 analysis, for example "Constrained K12.tre" is the tree file
 resulting from our implied weights analysis with weighting strength K=12
 and a molecular constraint. Set 3 contains 3D STL files of the segmented
 anatomy of *Helioscopos dickersonae*. The STLs presented herein were
 produced from microCT data collected at the University of Texas
 High-Resolution X-ray CT Facility (180 kV, 0.13μA, no filter, 1400
 projections, 2 frames per projection), and segmented in 3Dslicer and
 VGStudio Max 3.5. These files are named for the element they represent,
 for example "Dentary (R).stl" is the right dentary. Set 4
 contains tiffs of all of the supplemental figures in the manuscript. This
 is on Zenodo. Set 5 contains the modified phylogenetic dataset used for
 our time calibrated bayesian analysis, as well as the maximium clade
 crediblity tree file and the final xml file of the analysis conduced in
 BEAST 2.6.6. The matrix is "modifed_bayesoan_Helioscopos.nex,"
 while the tree file is "Helioscopos_12SUM.tree," and the xml
 file is "Helioscopos_final_run.xml." ## Description of the data
 and file structure We recommend viewing our nexus files (.nex) in Mesquite
 (at whatever the current version is at the time of a user accsessing this
 data). A download link for Mesquite can be found here:
 . Our tree files (.tre) are best
 viewed in FigTree, available here:
 . However there are also
 R packages capable of openeing these files for the purpose of tree
 visualization. Our STL files can be viewed in the native Windows software
 Paint3D, as well as in a number of other programs (both freeware and
 otherwise) designed to work with 3D data. These include Meshlab
 () and Blender
 ().