DOI: 10.5061/dryad.p2ngf1vwm
title: Data from: The dentary of hadrosauroid dinosaurs: evolution through heterochrony

description: The near-global success reached by hadrosaurid dinosaurs during the
 Cretaceous has been attributed to mastication, a behaviour commonly
 recognized as a mammalian adaptation. Its occurrence in a non-mammalian
 lineage should be accompanied by the evolution of several morphological
 modifications associated with food acquisition and processing. This study
 investigated morphological variation in the dentary, a major element of
 the hadrosauroid lower jaw. Eighty-four hadrosauroid dentaries were
 subjected to geometric morphometric and statistical analyses to
 investigate their taxonomic, ontogenetic, and individual variation.
 Results suggest increased food acquisition and processing efficiency in
 saurolophids through a complex pattern of evolutionary and growth-related
 changes. The edentulous region grew longer relative to dentary length,
 allowing for food acquisition specialization anteriorly and processing
 posteriorly, and became ventrally directed, possibly associated with
 foraging low-growing vegetation, especially in younger individuals. The
 saurolophid coronoid process became anteriorly directed and relatively
 more elongate, with an expanded apex, increasing moment arm length, with
 muscles pulling the jaw more posteriorly, increasing mechanical advantage.
 During growth, all hadrosauroids underwent anteroposterior dental battery
 elongation by the addition of teeth, and edentulous region ventralization
 decreased. The dental battery became deeper in saurolophids by increasing
 the number of teeth per tooth family. The increased coronoid process
 anterior inclination and relative edentulous region elongation in
 saurolophids are hypothesized to have evolved through hypermorphosis
 and/or acceleration, peramorphic heterochronic processes, and the
 anteroposteriorly shorter but dorsoventrally taller saurolophid dentary,
 likely emerged due to post-displacement in dental battery elongation and
 edentulous region decreased ventral orientation, a paedomorphic
 heterochronic process.
description: The dataset was collected from the literature (see the
 publication's online Supporting Information for a dataset reference
 list) and digital libraries of Dr. Albert Prieto-Márquez. Information
 pertaining to hadrosauroid dinosaur dentary specimens was written into the
 dataset using Excel. Images of specimens were made into a .TPS file in
 tpsUtil, and then digitized with equidistant semilandmark curves in
 tpsDIG2. The sliders file was created in tpsUtil. The .TPS file and
 sliders file were then transferred into the program R, and used together
 with the dataset (see the file
 "SOEDERBLOM_et_al_Appendix_S1.txt" in Zenodo or the
 publication's online Supporting Information), to analyze the
 digitized data, using the R script.
description: A text editor (e.g. Notepad [optional]), Excel, tpsUtil, tpsDIG2,
 and R are required to view and/or use the data files.
description: # Data from: The dentary of hadrosauroid dinosaurs: evolution through
 heterochrony *** The complementary dataset on hadrosauroid dinosaur
 dentaries, is stored on Zenodo, as well as with the publication "The
 dentary of hadrosauroid dinosaurs: evolution through heterochrony"
 supporting information, as a tab-delimited .txt file (Appendix S1). The
 dataset contains information such as specimen number, data source, page
 number, figure number, taxonomic, temporal, ontogenetic (growth stage),
 geographic and stratigraphic affinity (information on references used in
 the dataset is also found in the supporting information for the
 aforementioned publication). The dataset is utilized in analyzing
 hadrosauroid dentary morphology, using two-dimensional geometric
 morphometrics. ## Description of the data and file structure
 SOEDERBLOM\_et\_al\_Data \|\- SOEDERBLOM\_et\_al\_Appendix\_S1\.txt
 \(stored at the Zenodo archive\) \|\-
 SOEDERBLOM\_et\_al\_TPS\_file\_Hadrosauroid\_Dentary\.TPS \|\-
 SOEDERBLOM\_et\_al\_Sliders\_file\_Hadrosauroid\_Dentary\.txt \|\-
 SOEDERBLOM\_et\_al\_Script\_Hadrosauroid\_Dentary\_REVISED\.R \(stored at
 the Zenodo archive\) The dataset
 ("SOEDERBLOM\_et\_al\_Appendix\_S1.txt"), along with a .TPS file
 ("SOEDERBLOM\_et\_al\_TPS\_file\_Hadrosauroid\_Dentary.TPS")
 compiled in the program tpsUtil (Rohlf 2017a) and digitized in the program
 tpsDIG2 (Rohlf 2017b) containing the landmark X and Y coordinates of
 aforementioned digitized images of hadrosauroid dentary specimens as well
 as an accompanying sliders file
 ("SOEDERBLOM\_et\_al\_Sliders\_file\_Hadrosauroid\_Dentary.txt")
 generated from the .TPS file in tpsUtil (Rohlf 2017a), are used in the
 statistical computing program R (R CORE TEAM 2013). ## Sharing/Access
 information Links to other publicly accessible locations of the data: *
 The dataset and dataset references will be accessible as supporting
 information (appendices) along with the accompanying published study. Data
 was derived from the following sources: * The data was derived from
 photographs and accompanying information obtained/provided by Dr. Albert
 Prieto-Márquez from multiple different natural history collections visits,
 as well as from published literature (see Appendix S2 for dataset
 references, and the column "Source" in the dataset Appendix S1.
 Both are uploaded as supporting information with the study at the
 publisher, and Appendix S1 is additionally uploaded to Zenodo). ##
 Code/Software In R (R CORE TEAM 2013) version 4.1.3, the script file
 ("SOEDERBLOM\_et\_al\_Script\_Hadrosauroid\_Dentary\_REVISED.R",
 uploaded to Zenodo) is used to run all analyses, which rely on the package
 geomorph (Adams & Otárola-Castillo 2013) version 3.2.1. By
 following the script from up to down, including importing the
 aforementioned dataset, the .TPS file and sliders file (changing the file
 path or name of the file in the script when appropriate) when the script
 states so, and running the analyses in the script, data used in the study,
 and more, can be used to generate tables, figures and statistics. The
 exception is the quantile-quantile (Q-Q) plot which supports the use of
 parametric tests. This plot has to be generated externally, using for
 example the program Excel, using the data file output by the code in the R
 script to the work directory. ## References ADAMS, D. C. and
 OTÁROLA-CASTILLO, E. 2013. Geomorph: an R package for the collection and
 analysis of geometric morphometric shape data. Methods in Ecology and
 Evolution, 4, 393–399. R CORE TEAM 2013. R: a language and environment for
 statistical computing. R Foundation for Statistical Computing.
 http://www.R-project.org ROHLF, F. J. 2017a. TpsUtil. New York.
 http://life.bio.sunysb.edu/morph/ ROHLF, F. J. 2017b. TpsDIG2. New York.
 http://life.bio.sunysb.edu/morph/