DOI: 10.5061/dryad.bt4vj
title: Data from: The role of inhibitory dynamics in the loss and re-emergence of macropodoid tooth traits

description: The reversibility of phenotypic evolution is likely to be strongly
 influenced by the ability of underlying developmental systems to generate
 ancestral traits. However, few studies have quantitatively linked these
 developmental dynamics to traits which re-evolve. In this study we assess
 how changes in the inhibitory cascade, a developmental system that
 regulates relative tooth size in mammals, influenced the loss and
 reversals of the posthypocristid, a molar tooth crest, in the kangaroo
 superfamily Macropodoidea. We find that posthypocristid loss is linked
 with reduced levels of posterior molar inhibition, potentially driven by
 selection for lophodont, higher-crowned molar teeth. There is strong
 support for two posthypocristid reversals, each occurring after more than
 15 million years of absence, in large-bodied species of Macropus, and two
 giant extinct species of short-faced sthenurine kangaroo (Procoptodon). We
 find that whereas primitive posthypocristid expression is linked to higher
 levels of posterior molar inhibition, re-emergence is tied to a relative
 increase in third molar size associated with increasing body mass,
 producing molar phenotypes similar to those in mouse where the
 ectodysplasin pathway is up-regulated. We argue that although shifts in
 the inhibitory cascade may enable re-emergence, dietary ecology may limit
 the frequency of phylogenetic reversal.
description: READ_MEcrownH_dataExtant macropodoid crown height data based on measurements of museum specimens. "ID" specimen collection number,"Side" = describes if the specimen is a left (L) or right (R) dentary."Source" = collection holding specimen (AM= Australian Museum Sydney, SAM= South Australian Museum Adelaide, WAM= Western Australian Museum Perth, FU= Flinders University Vertebrate Palaeontology Laboratory Adelaide , ANWC= Australian National Wildlife Collection Canberra, NTM= Northern Territory Museum, Alice Springs), "PW"= posterior width, "PHb"=Molar crown height measured at the hypoconid, "Tooth_identity"= molar position of the tooth.FADChronostratigraphic data on macropodoid first appearances in the fossil record. Data was compiled in Excel and exported as text file. As described in the papert the "FAD" corresponds to the earliest representative of the lineage while "LAD" refers to the first appearance of the tip taxon associated with that respective branch. All numeric values refer to millions of years before present (Myr). Tip taxa correspond to those in the morphological phylogeny.Molecular_tree_statesTree states relating to a pruned version of the molecular phylogeny originally produced by Mitchell et al. (2014; see paper text for full citation). Data was compiled in Excel and exported as text file. "1" = Posthypocrsitid present, "0" = Posthypocrsitid absent.Morphological_tree_statesCharacter states for the modified morphological phylogeny originally produced by Prideaux and Warburton (2010; see in paper text for full citation). "1"= Posthypocrstid presemy, "0"= posthypocristid absent. Data was originally compiled in excel and exported as a text file.Morphological phylogenyModified (see paper text) most parsimonious morphological input tree from Prideaux and Warburton (2010).mpts.treTimescaled morphological phylogeny of MacropodoideaOutput timescaled morphological phylogeny from R in Newick tree file.mpts_Tscale.trePosthypocrstid_relief_dataPosthypocristid relief data based on CT scan measurements in Avizo 8. PHCvert=vertical posthypocristid relief, PHCwdith= width across the talonid fossa at its point of maximum relief, Relief_Ratio = the quotient of PHCvert by PHCwidth. Comment= describes whether the crest is a homologue or analogue of the posthypocristid.PHC_relief_data.txtTooth_dimensionsTooth dimension data based on museum collection specimens."ID"= Specimen number, "Side"= specimen is left ("L") or right ("R") dentary, "Origin"= collection holding specimen (AM= Australian Museum Sydney, BMNH= British Museum of Natural History, SAM= South Australian Museum Adelaide, UCMP= University of California Museum of Paleontology, QVM= Queen Victoria Museum, Inveresk, Tasmania, WAM= Western Australian Museum Perth, FU= Flinders University Vertebrate Palaeontology Laboratory Adelaide , ANWC= Australian National Wildlife Collection Canberra, NTM= Northern Territory Museum, Alice Springs, QM=Queensland Museum, Brisbane), "AW"= maximum anterior molar width, "PW"= maximum posterior width, "L"= maximum molar length, "Tooth_id" = molar tooth position, "Collector"= observer responsible for measurement (AC= Aidan Couzens, GJP= Gavin J. Prideaux).SurfaceFilesSurface files exported from MeshLab v1.3.3 64bit. Naming convention is "Institution_SpecimenNumber_Species_Element.ply". Institutional abbreviations: Australian Museum (AM), Australian National Wildlife collection (ANWC), Flinders University Vertebrate Palaeontology Laboratory (FU), Northern Territory Museum Alice Springs (NTM), Queensland Museum (QM), South Australian Museum (SAM), University of California Musuem of Paleontology (UCMP), Wesetern Australian Museum (WAM). Element abbreviations: LRMX= Lower right (or left;L) molar (X denotes tooth number (1-4); X if unknown), OES= Outer enamel surface, EDJ= Enamel-dentine junction, ENAM= Enamel cap, DENT= Dentine, RMAND= Right (or left;L) mandible.Sum_m3HI_byWSummary Crown heigh data for living macropodoids exported from R. Taxa= Species, MeanPhyb= Hypsodonty index calculated as mean hypoconid crown height divided by max talonid width, sePhyb= bootstrap estimate of standard error.Posterior_sequence_ratiosSummary posterior molar proprtion data (m2-4) for Macropodoid taxa exported from R. Summary statistics (mean, sample size; n, standard deviation;sd) for m3/m2 and m4/m2.R_scriptsR script files compiled in the program TinnR.