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Title Herbivorous jaw disparity and its relationship to extrinsic evolutionary drivers

Authors MacLaren, JA; Anderson, PSL; Barrett, PM; Rayfield, EJ

Date Submitted 2017-03-03 Supplementary Information

Herbivorous dinosaur jaw disparity and its relationship to extrinsic evolutionary drivers

Authors: Jamie A. MacLaren1*, Philip S. L. Anderson2, Paul M. Barrett3 & Emily J. Rayfield4*

1Department of Biology, Universiteit Antwerpen, Campus Drie Eiken, Universiteitsplein, Wilrijk,

Antwerp, 2610, Belgium. 2Department of Biology, University of Illinois at Urbana-

Champaign, 515 Morrill Hall, 505 S. Goodwin Ave., Urbana, IL 61801, USA. 3Department of Earth

Sciences, The Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK. 4School of Earth Sciences, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK.

* Corresponding authors: JM ([email protected]) or EJR ([email protected])

TABLE OF CONTENTS

1. Study Materials

2. Landmark Descriptions

3. Functional Characters

4. Analytical Methodology

5. Additional Graphical Results

a. placement in morphospace

b. Functional loadings

c. Biomechanical disparity with -rich formations removed

d. Mean pairwise distance

e. Feeding height stratification

6. Specimen List incl. institutional abbreviations

7. Supplementary References

1. Study Materials

Mandibular shape and measurement data were collected from a variety of sources, including museum collections, the literature and computer tomographic (CT) scans. First-hand data acquisition involved examination and photography of 32 specimens in the Natural History Museum, London. Photographs were taken using a Nikon D3000 DSLR camera, mounted on an adjustable tripod for stability. were photographed in lateral view and medial and dorsal views where available. CT scans were uploaded into

Avizo 6.3 (VGS Inc.) and images taken from visual outputs. These images were scaled using published information on the specimens in question. Mandibular materials from the published literature required a readable or calculable scale; jaw material with no scale was only used if a scale could be estimated from other sources, such as author correspondence. Reconstructed jaw material was used, though critically; any reconstructions were made with reference to complete material from conspecifics. Six juvenile and sub-adult specimens were included in the data set; these were not used as proxies for adults, but were treated as different taxa for the purpose of examining morphospace and function-space occupation. Where appropriate, multiple specimens of one or species were analysed to establish intraspecific variation in morphospace and function-space occupation. In total, 167 specimens were included in the analysis.

2. Landmark Definitions

Two-dimensional landmarks were applied to homologous and analogous points on images of dinosaur jaws using tpsDig II software. Six fixed landmarks were described, identifying points on both sauropodomorph and ornithischian jaws (Supplementary Figure 1.). The overall morphology of each jaw was described by a series of sliding semi-landmarks (sLM).

Supplementary Figure 1. Fixed landmark placement on sauropodomorph (top) and ornithischian lateral lower jaws. Jaw representatives: () and (:

Marginocephalia). Images from Yates (2007) and Ryan et al. (2012).

The six fixed landmarks (Lm) were placed at points on lateral jaw images which are visible in all images. Landmarks were placed at meetings of three sutures ( 1 Lm) or apexes of mandibular components (Type 2 Lm) (Zelditch et al. 2012). Lm1 (T2) is the apex of the anterior dentary .

Lm2 (T2) is the anterior margin of the toothrow. Lm3 (T2) is the posterior margin of the toothrow.

Lm4 (T1) is the dorsal point between the dentary and the surangular (as viewed laterally).

Lm5 (T2) is the posterior apex of the jaw. Lm6 (T1) is the ventral suture point between the dentary

and the angular (as viewed laterally). Jaw morphology between the fixed landmarks was described by six semilandmark (sLm) curves. A fixed number of sliding semi-landmarks comprised each curve: landmark 1–2 (7 sLm), 2–3 (10 sLm), 3–4 (15 sLm), 4–5 (20 sLm), 5–6 (15 sLm), 6–1 (15 sLm) for a total of 82 semi-landmarks. In total, 88 landmarks (both fixed and sliding) were described. Semi-landmarks were slid using the Chord-d2 technique to minimise Procrustes distances rather than bending energy.

3. Functional Character Definitions

Biomechanical character definitions are illustrated on diagrams of mandibles from Melanorosaurus (Yates

2007) and where necessary Protoceratops (Ryan et al. 2012).

C1. Anterior Mechanical Advantage: Mechanical advantage (the ratio of moment arms) represents the proportion of applied input muscle force transferred to the functional tooth-row (Westneat 1994). Moment arms in this study are approximated as the measurement from the centre of the joint of articulation to the centre of adductor insertion. Output moment arm is measured from the joint to the anterior most dental tip; this measure represents the lowest mechanical advantage along the jaw. For ornithischians, this is measured from the tip of the predentary, whereas for sauropodomorphs it is measured from the tip of the dentary.

C2. Posterior Mechanical Advantage: As above, however the output moment arm is measured from the articular joint to the posterior dental surface (as viewed from lateral images); this represents the highest potential mechanical advantage along the (Westneat 1994). Some ceratopsians and hadrosauroids possess tooth batteries that extend behind the coronoid process, and are not visible in lateral views. For consistency the output moment arm was measured to the posterior visible dental surface.

C3. Opening Mechanical Advantage: Opening mechanical advantage is the ratio between the opening in-lever and (in this case) the maximum out-lever; it represents a proxy for the velocity during jaw opening (Westneat

1994). A force applied to a short in-lever will cause a greater response at the opposite end of the beam (in this case the jaw). The in-lever here is from the jaw articulation (acting as a fulcrum) to the retroarticular process.

The out-lever is from the articulation to the anterior tip of the jaw. The maximum extent of the retroarticular process was taken as the furthest point of the jaw posterior to the articulation. High values represent slow biting mechanism.

C4. Maximum Aspect Ratio: Second moment of area is a measure of flexural stiffness, and ordinarily requires cross-sectional area of the beam (jaw) to calculate; as the majority of the jaws under investigation will be stressed primarily in the dorsoventral plane (rather than anteroposterior), jaw aspect ratio may be used as a proxy for flexural stiffness of the jaw (Anderson et al. 2011, 2013). To determine maximum potential stiffness the greatest depth measurement along the jaw is taken and divided by the total jaw length; this is the aspect ratio of the jaw, and represents a proxy for flexural stiffness of the jaw.

C5. Average Aspect Ratio: Average flexural stiffness across the jaw is estimated by taking the area of the jaw

(excluding teeth) and dividing by the total length (Anderson et al. 2011). Area is divided by length twice to determine the average depth/length ratio rather than simply the average depth.

C6. Relative Adductor Fossa Length: Muscle output force is directly proportional to cross-sectional area of the muscle in question; the jaw adductor attachment is therefore a proxy for the potential muscle force exhibited during jaw adduction (i.e. biting). The adductor fossa represents the site of muscle attachment on the medial surface of the jaw, and the greatest length is therefore measured to represent maximum muscle cross- section. For jaws with no medial view, the maximum muscle attachment is determined as the distance from the posterior visible tooth-row (in lateral view) to the leading edge of the jaw articulation; this represents the maximum possible adductor attachment (Anderson et al. 2011).

C7. Relative Dental Row Length: The greater the length of the tooth-row, the greater variation in biting force and speed may be observed, in addition to potential for greater variability in form and function of specific teeth. The predentary of ornithischians is here included as part of the functional tooth-row, as a rhamphotheca was present on all ornithischian predentaries (Norman et al. 2004). Relative dental length is measured as a ratio of total jaw length and total tooth-row length.

C8. Relative Articular Offset: The location of the jaw articulation relative to the line tangent of the tooth-row affects how the jaws occlude; an articulation close to the line tangent suggests ‘scissor-like’ occlusion, found primarily in carnivores. A jaw articulation far from the line tangent of the tooth-row implies a ‘vice-like’ occlusion, common in herbivorous and durophagous taxa (Galton 1985; Ramsay and Wilga 2007). This offset of the jaw joint enables teeth in the upper and lower jaws to meet simultaneously during occlusion, which is especially effective for gripping soft items or crushing tough prey items (Ramsay and Wilga 2007). Articular offset is measured by calculating the perpendicular distance between the line-tangent of the tooth-row and the jaw articulation. The length of this line is divided by total jaw length to estimate deviation from a scissor-like jaw action. The base of the tooth-row is used instead of the tooth tips (Ramsay and Wilga 2007; Anderson et al. 2011) due to the scarcity of in situ teeth in several .

C9. Relative Area of Mandibular Fenestration: The mandibular fenestra is a muscle attachment site in , and allows expansion of jaw adductor musculature (Holliday and Witmer 2008). A perforation in the jaw, however small, may have some effect on the mechanical limits of the jaw, and should therefore be quantified. The total lateral area of mandibular fenestrae is measured and then divided by the total lateral area of the jaw.

C10. Relative Dental Curvature: Down-curvature of the tooth-row has been suggested to represent a herbivorous trait in theropods (Zanno and Makovicky 2011). Curvature of the tooth-row may have biomechanical functions, such as application of shear forces during mastication rather than simply compressive forces (Ramsay and Wilga 2007). The relative curvature of the tooth-row was quantified by calculating the highest/deepest section of tooth-row offset from the chord and then dividing by the chord length of the tooth-row.

C11. ‘Cheek’ Tooth Height/Width and C12. ‘Premaxocc’ Height/Width (Sauropodomorpha only)

Tooth shape has been shown to have an effect on the capacity of the tooth to resist structural fracture, and inflict fracture in the food item. The ratio of height to maximum width of tooth is here used as a proxy for cusp angle.

Due to the fundamental differences in composition between ornithischian and saurischian jaws, assessment of tooth cusp angle requires some compromise. Dentary teeth in ornithischians were all considered

‘cheek’ teeth, whereas teeth in saurischian jaws were split into ‘premaxocc’ teeth and ‘cheek’ teeth.

Premaxillary occluding teeth (‘premaxocc’) are defined here as anterior mandibular teeth which would occlude with the premaxillary teeth of the anterior ; these may be considered as teeth suited for cropping fodder rather than crushing it. Cheek teeth are defined here as all teeth posterior to ‘premaxocc’ teeth in sauropodomorphs; in cerapodan ornithischians, these teeth are heavily involved in food processing. The maximum height and width of the largest tooth in the ‘cheek’ and ‘premaxocc’ regions were taken, and then height was divided by width. The largest tooth is most likely to be the most mature, least worn and maximum possible size of tooth for the given organism, so it is the best tooth to take to retain consistency. Ornithischian

‘premaxocc’ teeth were coded as N/A, due to the edentulous of the ‘premaxocc’ region in ornithischians.

C13. ‘Cheek’ Tooth Packing: The greater number of teeth tightly packed in a tooth-row, the greater the occlusion potential of the jaw, and therefore the more potential for food processing, even with simple orthal movements (Upchurch and Barrett 2000; Ramsay and Wilga 2007). Tooth packing can therefore be used as a proxy for amount of processing potential the teeth possess. Tooth packing was calculated by taking the gaps between ‘cheek’ teeth and dividing the cumulative total by the breadth of the largest ‘cheek’ tooth; dental batteries (present in many ceratopsids and hadrosaurids) were coded as ‘0’ for gaps.

C14. ‘Premaxocc’ Tooth Procumbency: The teeth at the anterior of the sauropodomorph tooth-row show varying degrees of procumbency (projection rostrally from the tooth root). The angle of a tooth affects the forces exerted on prey (e.g. foliage) during the biting action (Ramsay and Wilga 2007); highly procumbent teeth therefore exhibit different forces on prey items compared to teeth that sit perpendicular to the tooth-row.

Tooth procumbency is measured as the angle from the chord base of the tooth-row to the long axis of the largest tooth in the ‘premaxocc’ region. Ornithischian tooth procumbency is coded as N/A due to the lack of teeth and the presence of a predentary in the ‘premaxocc’ region.

C15. Tooth Height Relative to Jaw Depth: Tooth height to jaw depth ratios help identify specialised more suited to capturing, slicing or crushing (Anderson et al. 2011). Taking the ratio of tooth height to the jaw

depth represents a measure of how tall the teeth are compared to the jaw. Tooth height is measured as the maximum height of the largest tooth in the entire jaw, disregarding ‘cheek’ and ‘premaxocc’ regions. The jaw depth is taken as the depth of the jaw perpendicular to the base of the largest tooth.

C16. Relative Symphyseal Length: The morphology of the mandibular symphysis has been shown to affect the resistance of the jaw to lateral transverse bending (movement of the posterior jaw out and the very anterior jaw in) during the power stroke of mastication (Vinyard and Ravosa 1998; Daegling 2001). Symphyseal flexibility has also been shown to affect oral processing in modern herbivorous (Jones et al. 2012).

The symphyseal joint is therefore key in resisting shear stress and torsion; the relative length of the symphyseal joint can therefore be taken as a proxy for symphysis robustness. For jaws with medial views, the long axis of the mandibular symphysis was measured, and then divided by the mandibular length.

C17. Symphyseal Orientation: The symphyseal angle has been shown to also affect the mandibular resistance to stress and strain in paired mandibles (Daegling 2001). Symphyseal angles showing a steep incline (~90°) have been shown to resist transverse bending and stresses during biting in primates (Daegling 2001). The

angle of the symphysis is taken as 180° minus the angle between the jaw line and a line running parallel to the long axis of the mandibular symphysis.

C18. Predentary Offset: Ornithischian predentaries show a great deal of variation throughout different clades.

The bone may be ventrally or dorsally offset from the tooth-row, dependent on the functional role the predentary performs for the in question. For this analysis, deflection of the predentary tip dorsally

(‘incisiform’) or ventrally (‘spatulate’) from the tooth-row is calculated as for articular offset, i.e. away from horizontal (‘platyform’). Perpendicular distance from the chord of the tooth-row is taken, and then divided by respective mandibular length.

4. Analytical Methodology

Functional variation of 167 jaws of herbivorous was assessed using 18 biomechanical characters with known functional and ecological implications. Functional characters were measured from images of jaw material in lateral view; all characters coded were continuous, although some characters were present only in certain clades and as such only affected functional space occupation for the in question. All character scores were calculated from measurements taken in ImageJ (Schneider et al. 2012) and then subjected to Z- transformation before analysis. Z-transformation standardises the measurements, accounting for greater ranges of measurement dependent on the biomechanical trait in question. Z-transformation gives each character an average value of 0 and standard deviation of 1:

ai – ā Zi =

sa where ai is the measurement for the ith taxon, ā is the mean value for the character across all taxa and sa is the standard deviation of the resultant scores for all taxa (Anderson et al. 2011).

Procrustes coordinates for morphological data (outputs from relative warp analyses) were analysed using principal component analysis (PCA) in PAST v.3 (Hammer et al. 2001). PCA were carried out on a dataset of both sauropodomorph and ornithischian taxa (n = 167), and then on four smaller datasets to test intra-clade variation: Sauropodomorpha (n = 44), (n = 22), (n = 42) and (n =

59). Heterodontosaurids + were excluded from intra-clade analysis for taxonomic simplicity, as they represent a very small group that does not belong to any major clade. Axes produced in PCA were then assessed for significant contribution to variation; axes which contributed >1% of variance within the sample were selected for disparity analyses. PC axes comprising the greatest variance were plotted to visually assess occupation of morphospace for each taxonomic dataset in question. Morphological variation between different taxonomic groups were assessed for significance using non-parametric multivariate analysis of variance

(NPMANOVA) in PAST v.3 (Anderson 2001); data from Euclidean distance measurements were subjected to

Bonferroni corrections to compare two or more groups (Holm 1979). The standardised functional character

matrix underwent principal coordinates analysis (PCo) using the Gower model to produce biomechanical morphospace (‘functionspace’) plots; PCo was used instead of PCA due to missing data in the functional assessment. Resultant PCo axes were tested for significance using NPMANOVA. Principal components analysis was later performed on the functional character matrix to ascertain the contribution of each character to the composition of the principal axes (see Functional Loadings). All these analyses were performed in

PAST v.3.

Disparity assessments were carried out for two variables: temporal range and maximum feeding height.

Disparity was assessed for both morphological and functional data matrices using the Morphological Disparity

Analysis (MDA) add-on for MATLAB® (Navarro 2003). The sum of variance disparity metric was favoured, with additional analyses run using the mean pairwise distance metric. These disparity metrics are both robust to uneven sampling of data and statistical outliers (Ciampaglio et al. 2009). Single group analyses were carried out and 1000 bootstrap repetitions were implemented, producing 95% confidence intervals and eliminating the requirement for rarefaction. Significant changes between time bins were assessed using pairwise t-testing, with Bonferroni corrections being applied where appropriate (Holm 1979). In addition, marginal likelihood assessment of variance between disparity bins was implemented (Finarelli and Flynn 2007); both t-testing and marginal likelihood estimates were carried out using the statistical programming language R (R Core

Development Team 2008). Marginal likelihood estimates assess variance between adjacent data bins (e.g. time-bins); a likelihood ratio of 8< is considered a likely result (Finarelli and Flynn 2007). Pairwise t-testing was used to assess significance of changes between data bins. Sum of variance metric was used for t-testing.

Results for sum of variance and mean pairwise distance showed negligible difference, and it was agreed by the authors that MPD could be used for disparity analyses despite a different metric used for marginal likelihood.

5. Additional Graphical Results a) Species placement in morphospace

Supplementary Figure 2a: Shape-based morphospace occupation by Sauropodomorpha (PC1 v PC2). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 2b: Biomechanical morphospace occupation by Sauropodomorpha (PCo1 v PCo2).

Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 2c: Biomechanical morphospace occupation by Sauropodomorpha (PCo1 v PCo3).

Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 3a: Shape-based morphospace occupation by ‘’ Ornithichia (PC1 v PC2). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 3b: Biomechanical morphospace occupation by ‘basal’ Ornithischia (PCo1 v PCo2).

Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 3c: Biomechanical morphospace occupation by ‘basal’ Ornithischia (PCo1 v PCo3).

Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 4a: Shape-based morphospace occupation by Thyreophora (PC1 v PC2). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 4b: Biomechanical morphospace occupation by Thyreophora (PCo1 v PCo2). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 4c: Biomechanical morphospace occupation by Thyreophora (PCo1 v PCo3). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 5a: Shape-based morphospace occupation by Marginocephalia (PC1 v PC2). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 5b: Biomechanical morphospace occupation by Marginocephalia (PCo1 v PCo2).

Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 5c: Biomechanical morphospace occupation by Marginocephalia (PCo1 v PCo3).

Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 6a: Shape-based morphospace occupation by Ornithopoda (PC1 v PC2). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 6b: Biomechanical morphospace occupation by Ornithopoda (PCo1 v PCo2). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

Supplementary Figure 6c: Biomechanical morphospace occupation by Ornithopoda (PCo1 v PCo3). Key of taxa can be used to identify specific taxon occupation of morphospace. Taxa in bold highlighted in main text.

b) Functional loadings

Functional loadings were estimated by performing principal components analysis (rather than coordinates analysis) on the biomechanical dataset. Taxa with missing data were excluded for the calculation of functional loadings, and resultant loadings were cross-referenced with jaw morphologies on PCo axes (main manuscript

Figures 2 and 3). This offers an insight into the loading of each biomechanical trait across several principal components.

Principal Component 1 (21.7%) Principal Component 2 (10.1%)

Principal Component 3 (8.7%) Principal Component 4 (8.1%)

Supplementary Figure 7. Positive PC1 is influenced by high loading from adductor musculature (adductor fossa length), tooth-row mechanical advantages, tooth packing and tooth:jaw height ratio. Negative PC1 is

dominated by aspect ratio loadings, associated with resistance to bending in dorso-ventral compression.

Positive PC2 is heavily influenced by tooth-row mechanical advantages. Negative PC2 is dominated by mandibular fenestra size. Positive PC3 is heavily influenced by tooth size and articular offset. Negative PC3 is dominated by opening mechanical advantage and tooth-row curvature. Positive PC4 is influenced by jaw aspect and features of the tooth-row (curvature, predentary morphology, dental row length and tooth packing).

Negative PC4 is dominated by the relative offset of the tooth-row from the jaw articulation. C1-18 correspond to biomechanical characters defined in Section 3: Functional Character Definitions (see Table 1 for character descriptions).

c) Biomechanical disparity with Jurassic fossil-rich formations removed

Supplementary Figure 8. Biomechanical disparity curves (sum of variance metric) created with the exclusion of major Jurassic Lagerstätte. i) exclusion of taxa from the Morrison Formation (Western

USA). ii) exclusion of taxa from the Shaximiao (Dashanpu) Formation. Grey region spans the 95% confidence intervals based on 1,000 bootstrap replicates. Biomechanical disparity (green dots) is plotted alongside jaw specimen sample size curve (blue diamonds).

d) Mean pairwise distance disparity through time

Supplementary Figure 9. Comparison of morphological and biomechanical disparity across 16 equal length time bins. Disparity curves based upon mean pairwise distance metric. Grey region spans the 95% confidence intervals based on 1,000 bootstrap replicates. Angiosperm radiation

(flower). A. morphological disparity curve (green) compared to jaw specimen sample size (blue). B. biomechanical disparity curve (green) compared to jaw specimen sample size curve (blue).

e) Feeding height stratification

Supplementary Figure 10. Sauropodomorph mandibular disparity at maximum feeding height. Sample diversity (left) of sauropodomorphs in sample is presented alongside biomechanical disparity (sum of variance). Maximum feeding height was determined as the maximum potential elevation of the head from published sources. Each taxon falls within one feeding envelope. Example taxa for each feeding envelope: 0-

3m (), 3-6m (), 6-9m (), >9m (). Example floras from each storey are represented diagrammatically; from top: (gymnosperm), Magnoliaceae

(angiosperm), Cyatheales (tree ), Cycadales (), Pteridopsida (). Silhouettes adapted from Paul

2010.

Taxon designation for maximum feeding height (used in Supplementary Figure 10):

0 – 3 m 3 < 6 m 6 < 9 m 9m < Pampadromaeus Plateosaurus ‘gracillis’ youngi tianfuensis P. ‘erlengbergensis’ M. sinocanadorum P. ‘engelharti’ Camarasaurus grandis M. jingyanensis P. longiceps C. lentus Brachiosaurus kaalae Lamplughsaura Melanorosaurus (juv.) Camarasaurus (juv.) Diplodocus Abrosaurus

6. Specimen List

Taxon Specimen Source Sauropodomorpha barberenai ULBRA-PTV016 (Cabreira et al. 2011) Pantydraco caducus NHMUK P24 (Yates 2003a) Efraasia minor SMNS 12216, 12684, (Yates 2003b) 12667 Coloradisaurus brevis PVL 3967 (Galton and Upchurch 2004) Unaysaurus tolentinoi UFSM 11069 (Leal et al. 2004) Riojasaurus incertus ULR 56 (Bonaparte and Pumares 1995) Plateosaurus ‘gracilis’ GPIT 18318a (Yates 2003b) Plateosaurus ‘erlenbergiensis’ AMNH FARB 6810 (Prieto-Márquez and Norell 2011) Plateosaurus ‘engelharti’ SMNS 13200 (Yates 2003b) Plateosaurus ‘longiceps’ NHMUK R 4935 NHMUK Collections Massospondylus kaalae SAM-PK-K1325 (Barrett 2009) Adeopapposaurus mognai PVSJ610 (Martínez 2009) Lufengosaurus huenei IVPP V15 (Barrett et al. 2010a) Aardonyx celestae BP/1/6334 (Yates et al. 2010) Lamplughsaura dharmaramensis ISI R258/11-13 (Kutty et al. 2007) Melanorosaurus readi NM QR3314 (Yates 2007) Tazoudasaurus naimi TO 2000-1 (Peyer and Allain 2010) Shunosaurus lii ZG65430 (Chatterjee and Zheng 2002) Datousaurus bashanensis IVPP V 7262-7263 (Dong and Tang 1984) Omeisaurus tianfuensis ZDM T7501 (He et al. 1984) Mamenchisaurus sinocanadorum IVPP 10603 (Russell and Zheng 1993) Mamenchisaurus youngi ZDM 0083 (Ouyang and Ye 2002) Mamenchisaurus jingyanensis CV 00734 (Zhang et al. 1998) Jobaria tiguidensis MNN TIG 3-5 (Sereno 1999) Turiasaurus riodevensis CPT 1211 (Royo-Torres and Upchurch 2012) Diplodocus longus CM 11161 (McIntosh and Berman 1975) Diplodocus sp. CM 11255 (Whitlock et al. 2010) Abrosaurus dongpoensis ZDM 5038 (Ouyang 1989) Camarasaurus grandis GMNH PV 101 Ohio University Collections Camarasaurus lentus DINO 28 (Chatterjee and Zheng 2005) Camarasaurus lentus CM 11338 Ohio University Collections holgeri DFMMh/FV 291 NHMUK Collections Brachiosaurus sp. USNM 5730 (Carpenter and Tidwell 1998) Giraffatitan brancai S 116 (Janensch 1935) Euhelopus zdanskyi PMU R 233a (Mateer and McIntosh 1985) Abydosaurus mcintoshi DINO 16488 (Chure et al. 2010) Rapetosaurus krausei UA 8698 (Rogers and Forster 2004) Antarctosaurus wichmannianus MACN 6904 (Gallina and Apesteguía 2011) Bonitasaura salgadoi MPCA 460 (Gallina and Apesteguía 2011)

Malawisaurus dixeyi MAL 174 (Gomani 2005) Quaesitosaurus orientalis PIN 3906/2 (Kurzanov and Bannikov 1983) Tapuiasaurus macedoi MZSP-PV 807 (Zaher et al. 2011) Nemegtosaurus mongoliensis ZPM MgD-1/9 (Nowinski 1971) indet. MCF PVPH 272 (Gallina and Apesteguía 2011) Ornithischia Pisanosaurus mertii PVL 2577 (Bonaparte 1976) diagnosticus NHMUK RUB 17 (Norman et al. 2004) consors UCL B54 (Thulborn 1974) confuciusi STMN 26-3 (Zheng et al. 2009) Manidens condorensis MPEF-PV 3211 (Pol et al. 2011) tucki SAM-PK-K1332 (Norman et al. 2011) louderbacki ZDM 6011 (Barrett et al. 2010b) Thyreophora Emausaurus ernsti SGWG 85 (Haubold 1990) taibaii IVPP V 6728 (Sereno and Zhimin 1992) Gigantospinosaurus sichuanensis ZDM 0019 (Maidment et al. 2008) Jiangjunosaurus junggarensis IVPP V 14724 (Chengkai et al. 2007) mjosi HMNH 001 (Carpenter et al. 2001) Stegosaurus cf. armatus CM 41681 (Carpenter et al. 2001) Animantarx ramaljonesi CEUM 6228R (Carpenter et al. 1999) edwardsi AMNH 3035 (Carpenter and Kirkland 1998) Silvisaurus condrayi KUVP 10296 (Carpenter and Kirkland 1998) mirus ROM 1215 (Russell 1940) longiceps NMC 8531 (Sternberg 1928) Tarchia gigantea PIN 3142/250 (Tumanova 1977) chulsanensis GI SPS 100/151 (Maryanska 1977) Pinacosaurus grangeri IGM 100/1014 (Hill et al. 2003) Euoplcephalus tutus AMNH 5405 (Vickaryous and Russell 2003) magniventris AMNH 5214 (Carpenter 2004) Marginocephalia validum UA 2 NHMUK Collections downsi IVPP V 14530 (Xu et al. 2006) Liaoceratops yanzigouensis IVPP V 12738 (Xu et al. 2002) Auroraceratops rugosus IG-2004-VD-001 (You et al. 2015) Archaeoceratops oshimai IVPP V 11114 (You and Dodson 2003) Yamaceratops donrgobiensis IGM 100/1315 (Makovicky and Norell 2006) “Hongshanosaurus” houi IVPP V 12704 (You et al. 2003) ordosensis IVPP 07-0888-1 (You et al. 2003) Psittacosaurus lujiatunensis ZMNH M8137 (Zhou et al. 2006) Psittacosaurus neimongoliensis IVPP 12-0888-2 (Russell and Zhao 1996) Psittacosaurus “major” CAGS-IG-VD-004 (You et al. 2008) Psittacosaurus gobiensis LH PV2 (Sereno et al. 2010) Psittacosaurus mongoliensis AMNH 6254 (Sereno 2010)

Psittacosaurus sinensis NHMUK BPV149 (Sereno 2010) Bagaceratops rozhdestvenkyi ZPAL MgD 1/117 (Maryanska and Osmólska 1975) Gobiceratops minutus PIN 3142/299 (Alifanov 2008) Prenoceratops pieganensis MNHCM (no num) (Chinnery 2004) Leptoceratops gracillis CMN 8889 (Russell 1970) Unescoceratops koppelhusae TMP 95.12.6 (Ryan et al. 2012) Gryphoceratops morrisoni ROM 56635 (Ryan et al. 2012) Cerasinops hodgskissi MOR 300 (Chinnery and Horner 2007) cerorhynchus MOR 542 (Chinnery and Weishampel 1998) Udanoceratops tschizhovi PIN 3907/11 (Kurzanov 1992) Zhuchengceratops inexpectus ZCDM V0015 (Xu et al. 2010) Protoceratops hellenikorhinus IMM 95 BM1/1 (Lambert et al. 2001) Protoceratops andrewsi AMNH 6438 (Ryan et al. 2012) christopheri composite of MSM Ohio University Collections P2102, P3197, P2225, P4175, P4175, P4176, P4177, P4182 Avaceratops lammersi ANSP 15800 (Penkalski and Dodson 1999) Centrosaurus apertus UALVP 41 (Bell et al. 2009) albertensis CMN 344 (Ryan et al. 2010) Einiosaurus procurviornis MOR 456 (Sampson 1995) prorosus YPM 1822 (Horner and Goodwin 2006) Triceratops horridus cast of YPM 1820 OXFUM Collections Utahceratops gettyi UMNH VP 16784 (Sampson et al. 2010) richardsoni UMNH VP 17000 (Sampson et al. 2010) Tatankaceratops sacrisonorum BHI-6226 (Ott and Larson 2010) Coahuilaceratops magnacuerna CPC 276 (Loewen et al. 2010) Anchiceratops ornatus TMP 1983.001.0001 (Mallon et al. 2011) Titanoceratops ouranos AMNH 6325 (Longrich 2011) Agujaceratops mariscalensis composite of UTEP (Lehman 2010) P.37.7.062, 064, 067, 073, 082, 086 russelli NMC 2280 (Godfrey and Holmes 1995) Chasmosaurus belli NMC 0491 (Godfrey and Holmes 1995) Ornithopoda Changchunsaurus parvus JLUM L0403-j-Zn2 (Liyong et al. 2010) foxii various (NHMUK) (Norman et al. 2004) cincosaltenses MUCPv-208 (Coria and Salgado 1996) Parksosaurus warreni ROM 804 (Norman 2004) mackelai MOR 436 (Scheetz 1999) tilletti AMNH 3040 (Norman et al. 2004) robustus NHMUK R.3392 (Norman et al. 2004) altus CMN 3392 (Norman et al. 2004) Dryosaurus altus CMN 11340 (Carpenter 1994) lettowvorbecki unknown (Hubner and Rauhut 2010)

Dysalotosaurus lettowvorbecki BSPG AS I 834 (Hubner and Rauhut 2010) dispar unknown (Norman 2004) tetoriensius FPDM-V-40-1 (Kobayashi and Azuma 2003) bernissartensis IRSNB 1534 (Dollo 1883) Theiophytalia kerri YPM 1887 (Brill and Carpenter 2007) Dakotadon lakotaensis SDSM 8656 (Brill and Carpenter 2007) atherfieldensis NHMUK R 11521 (Norman 2004) Hippodraco scutodens UMNH VP 20208 (McDonald et al. 2010b) Altirhinus kuzanovi PIN 3386/8 (Norman 2004) nigeriensis MNHN GDF 300 (Norman 2004) byrdi SMU 74582 (Head 1998) Jinzhousaurus yangi IVPP V 12691 (Wang and Xu 2001) Jeyawati rugoculus MSM P 4166 (McDonald et al. 2010a) Equijubus normani IVPP V 12534 (Norman 2004) transsylvanicus NHMUK B.3386 (Horner et al. 2004) gobiensis PIN AN SSR 2232/1 (Norman 2004) caroljonesa CEUM 9758 (Norman 2004) insularis SC 57021 (Vecchia 2009) Huaxiaosaurus aighatens unknown (Zhao et al. 2011) annectens CMN 8509 (Horner et al. 2004) cast OXFUM Collections Edmontosaurus annectens (copei) AMNH 5730 (Horner et al. 2004) Kundurosaurus nagornyi AENM 2 921 (Godefroit et al. 2012a) blackfeetensis MOR 454, 447 (Horner 1992) Prosaurolophus maximus CMN 2870 (McGarrity et al. 2013) Prosaurolophus maximus ROM (McGarrity et al. 2013) Prosaurolophus maximus USNM (McGarrity et al. 2013) Prosaurolophus maximus ROM 787 (McGarrity et al. 2013) angustrirostris ZPAL MgD I/159 (Bell 2011) monumentensis ROM 6797 (Gates and Sampson 2007) Gryposaurus incurvimanus TMP 80.22.1 (Gates and Sampson 2007) Gryposaurus latidens AMNH 5465 (Horner 1992) Gryposaurus notabilis ROM 873 (Gates and Sampson 2007) canadensis MOR 794 (Cuthbertson and Holmes 2010) Acristavus gagslarsoni MOR 1155 (Gates et al. 2011) peeblesorum TCMI 2001.89.2 (Horner 1992) walkeri ROM 768 (Sullivan and Williamson 1999) Charonosaurus jiayinensis CUST J-V 1251-57 (Godefroit et al. 2000) Olorotitan arharensis AEHM 2/845 (Godefroit et al. 2012b) stebingeri MOR 549 (Evans 2010) Hypacrosaurus stebingeri composite RTMP (Horner and Currie 1994) 89.79.52, 87.79.206, 241, 333, 87.77.92 Hypacrosaurus altispinus CMN 8501 (Evans 2010)

Velafrons coahuilensis CPC 59 (Gates et al. 2007) casuarius AMNH 5240 (Horner et al. 2004) lambei TMP 66.04.01 (Horner et al. 2004) Lambeosaurus magnicristatus CMN 8705 (Horner et al. 2004) indet. 1 UALVP 11734 (Bell et al. 2009) Lambeosaurinae indet. 2 (juv.) MPZ 99/664-668 (Pereda-Suberbiola et al. 2009)

Abbreviations: AEHM, Amur Natural History Museum of the Far Eastern Insitiute of Geology and Nature

Management, Blagoveschensk, Russia; AMNH, American Museum of Natural History, New York, New

York, USA; ANSP, Academy of Natural Sciences of Philadelphia, Philadelphia, Pennsylvania, USA; BHI,

Black Hills Institute of Geological Research, Hill City, South ; BP, Bernard Price Institute for

Palaeontological Research, University of Witwatersrand, Johannesburg, South ; BSPG, Bayerische

Staatssammlung für Paläontologie und historische Geologie, Munich, ; CAGS, Institute of Geology,

Chinese Academy of Geological Sciences, Beijing; CEUM, College of Eastern Prehistoric Museum,

Price, Utah; CM, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA; CMN, Canadian

Museum of Nature, Ottowa, ; CPC, Colección Paleontológica de Coahuila Saltillo, Coahuila, Mexico;

CPT, Museum Fundación Conjunto Paleontológico de Teruel, Spain; CUST, Changchun University of

Science and Technology, Changchun, Jilin, ; CV, Municipal Museum of Chungquing, China; DFMMh,

Dinosaurier-Freilichtmuseum Münchehagen/Verein zur Förderung der Niedersachsischen Paläontologie,

Germany; DINO, Dinosaur National Monument, Utah, USA; FPDM, Fukui Prefectural Dinosaur Museum,

Fukui, Japan; GI SPS, Geologic Institute, Section of and , Ulan Baatar ; GMNH,

Gunma Museum of Natural History, Gunma, Japan; GPIT, Institut und Museum fur Geologie und

Paleontologie, Universitat Tubingen, Tubingen, Germany; HMNH, Hayashibara Museum of Natural History,

Okayama, Japan; IGM, Institute of Geology, Ulan Baatar, Mongolia; IMM, Inner Mongolian Museum,

Hohhot, China; IRSNB, Institut Royal des Sciences Naturelles de Belgique, Brussels, Belgium; ISI, Indian

Statistical Institute, Kolkata, ; IVPP, Institute of Palaeoanthropology and Palaeontology, Beijing, China;

JLUM, Geological Museum of the Jilin University, Changchun, China; KUVP, University of Kansas Natural

History Museum, Division of Paleontology, Lawrence, Kansas, USA; LH, Long Hao Institute of Geology and

Paleontology, Hohhot, China; MACN, Museo Nacional, Buenos Aires, ; MAL, Museum of Ancient

Life, Lehi, Utah, USA; MCF PVPH, Museo Carmen Funes, Paleontologia de Vertebrados Plaza Huincul,

Argentina; MNHCM, Mokpo Natural History and Cultural Museum, Mokpo, Korea; MNHN, Museum

National d’Histoire Naturelle, Paris, France; MNN, Museum National du Niger, Niamey, Republic of Niger;

MOR, Museum of the Rockies, Bozeman, ; MPCA, Museo Provincial Carlos Ameghino, Cipoletti,

Argentina; MPEF PV, Museo Paleontologico Egidio Feruglio, Trelew, Chubut, Argentina; MPZ, Museo

Paleontologico de la Universidad de Zaragoza, Zaragoza, Spain; MSM, Mesa Southwest Museum, Mesa,

Arizona, USA; MUCPV, Museo de Ciencias Naturales, Universidad Nacional del Comahue, Neuquén,

Argentina; MZSP PV, Museu de Zoologia da Universidade de São Paulo, São Paulo, ; NHMUK,

British Natural History Museum, London, UK; NM, National Museum, Bloemfontein, Free State, South

Africa; NMC, Canadian Museum of Nature, Ottowa, Canada (also see CMN); PIN, Paleontological Institute

Moscow, Moscow, Russia; PMU, Museum of Evolution, Uppsala University, Uppsala, Sweden; PVL,

Colección De Palaeontológia de Vertebrados, Instituto Miguel Lillo, Universidad Nacional de Tucumán,

Argentina; PVSJ, Museo de Ciencias Naturales, Universidad Nacional de San Juan, San Juan, Argentina;

ROM, , Toronto, Canada; SAM-PK, South African Museum, Cape Town, South

Africa; SC, Italian State Collection, Museo Civico di Storia Naturale, Trieste, Italy; SDSM, South Dakota

School of Mines and Technology, Museum of Geology, Rapid City, South Dakota, USA; SGWG, Sektion

Geologische Wissenschaften der Ernst-Moritz-Arndt-Universitat Greifswald, Germany; SMNS, Staatliches

Museum für Naturkunde, Stuttgart, Germany; SMU, Schuler Museum of Paleontology, Southern Methodist

University, Dallas, Texas, USA; STMN, Shandong Tianyu Museum of Nature, Pingyi, Shandong Province,

China; TCMI, The Children’s Museum of Indianapolis, Indiana, USA; TMP, Royal Tyrell Museum of

Paleontology, Drumheller, , Canada; TO, Musee des Sciences de la Terre de Rabat, Morocco; UA,

University of Alberta, Edmonton, Alberta, Canada; UALVP, University of Alberta Laboratory for

Paleontology, Edmonton, Alberta, Canada; UCL, University College London, London, UK; UFSM,

Universidad Federal de Santa Maria, , Brazil; ULBRA, Museu de Ciencias Naturais,

Universidade Luterana do Brasil, Canoas, Brazil; ULR, Universidad Nacional de La Rioja, La Rioja,

Argentina; UMNH, Utah Museum of Natural History, Salt Lake City, Utah, USA; USNM, United States

National Museum (Smithsonian Institution), Washington DC, USA; YPM, Yale Peabody Museum, New

Haven, Connecticut, USA; ZCDM, Zhucheng Dinosaur Museum, Zucheng, China; ZDM, Dinosaur

Museum, Zigong, China; ZMNH, Zhejiang Museum of Natural History, Hangzhou, Zhejiang Province,

China; ZPAL, Muzeum Ziemi Polska Akademia Nauk, Warsaw, Poland.

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