Evolution and Ecological Associations in Herbivorous Theropods Albert Chen 4/25/2016 Advisor: Dr. Thomas Holtz GEOL 394

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Abstract Theropod dinosaurs are inferred to have been ancestrally carnivorous and include numerous lineages specialized for hypercarnivory. However, evidence from fossil gut contents, anatomical characteristics, and phylogenetic bracketing suggests that several theropod clades convergently transitioned away from a carnivorous lifestyle to become herbivores or omnivores. The evolutionary drivers of these trophic shifts are unknown. Methods involving the use of the Paleobiology Database (PBDB) were used to test for the potential impact of ecological factors that may have affected the diversification of non-hypercarnivorous theropods, such as the diversity of other herbivorous vertebrates, the diversity of plants, and change in global sea level. After demonstrating feasibility of the proposed methods by using restricted parameters (solely considering oviraptorosaurian theropods from the Cretaceous of Asia and contemporaneous herbivores), said methods were applied to an expanded dataset including more than 500 taxa from 51 geologic formations. No statistically significant correlations were found between non- hypercarnivorous theropod diversity and that of plants, but overall diversity of non- hypercarnivorous theropods was found to positively correlate through space and time with the diversity of other herbivores. These results suggest that non-hypercarnivorous theropods did not strongly compete with contemporaneous herbivores. Instead, their diversity may have been promoted by the presence of other herbivores or by extrinsic environmental factors that favored herbivorous species as a whole.

Table of Contents Abstract ...... 2 Table of Contents ...... 2 Introduction and Background ...... 3 Method of Analysis ...... 6 Presentation of Data and Analysis of Uncertainty ...... 8 Case study ...... 8 Expanded dataset of herbivorous taxa ...... 18 Testing for correlation with plant diversity ...... 26 Testing for correlation with average global sea level ...... 27 Discussion of uncertainty ...... 27 Discussion...... 28 Suggestions for Future Work ...... 29 Conclusions ...... 30 Acknowledgements ...... 30 Bibliography ...... 30 Appendix A: Taxon Occurrence Data Used in Case Study ...... 35 Appendix B: Additional Herbivore Occurrence Data Used in Expanded Dataset ...... 46 Appendix C: Plant Occurrence Data ...... 71

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Appendix D: Average Global Sea Level of Examined Geologic Stages ...... 75 University of Maryland Honor Pledge ...... 76

Figure 1: Schematic of theropod skull morphology...... 4 Figure 2: Phylogenetic tree of theropods ...... 5 Table 1: Genus counts of oviraptorosaurs and potential competitors ...... 9 Figure 3: Oviraptorosaur diversity plotted against diversity of potential competitors ...... 11 Figure 4: Oviraptorosaur diversity plotted against diversity of other non-hypercarnivorous theropods ...... 12 Figure 5: Measures of diversity plotted against geologic stages ...... 13 Table 2: Calculated correlation coefficients for case study ...... 14 Figure 6: Residual diversity of oviraptorosaurs over time ...... 15 Figure 7: Residual diversity of other non-hypercarnivorous theropods over time ...... 16 Figure 8: Residual diversity of all potential competitors over time ...... 17 Table 3: Calculated correlation coefficients after correction of biases ...... 18 Figure 9: Expanded dataset of diversity plotted over time ...... 19 Figure 10: Residual diversity of all non-hypercarnivorous theropods over time (by DBCs) ...... 20 Figure 11: Residual diversity of all non-hypercarnivorous theropods over time (by DBFs) 20 Figure 12: Residual diversity of all potential competitors over time (by DBCs) ...... 21 Figure 13: Residual diversity of all potential competitors over time (by DBFs) ...... 21 Table 4: Calculated correlation coefficients using expanded herbivore dataset...... 22 Table 5: Calculated correlation coefficients relating theropod and plant diversity ...... 27 Table 6: Calculated correlation coefficients relating theropod diversity and average global sea level ...... 27

Introduction and Background Theropods are a diverse group of dinosaurs, comprising numerous disparate species both extant (in the form of birds) and extinct. Theropods are ancestrally carnivorous and encompass all dinosaurs known to be specialized for carnivory (Hendrickx et al., 2015). However, some Mesozoic theropods preserve fossil evidence of departure from a hypercarnivorous lifestyle, including plant material found as gut contents (Zhou and Zhang, 2002; Zheng et al., 2011; Ji et al., 2012) and gastroliths suggestive of a gastric mill similar to modern herbivorous birds (Ji et al., 1998; Kobayashi et al., 1999; Ji et al., 2003; Zhou and Zhang, 2006; Xu et al., 2009; Lee et al., 2014; Wang et al., 2016). In 2011, Zanno and Makovicky identified 21 morphological characters strongly correlated with herbivory in Mesozoic theropods: a downturned dentary symphyseal region (1); a rostrally projecting dentary symphysis (2); a ventrally concave cranioventral margin of the dentary (3); rostral (4), caudal (5), or total (6) tooth loss in the

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dentary; conical dentary (7) or premaxillary (8) teeth, particularly the rostralmost dentition (9); symmetrical teeth (10); loss of ziphodonty (blade-shaped teeth) (11); elongate (12), procumbent (13), or unserrated (14) premaxillary teeth; tooth loss in the premaxilla (15); lack of pronounced replacement waves of teeth (16); lanceolate (lance-shaped) cheek teeth (17); heterodont dentition (teeth varied in shape) (18); densely-packed dentition (19); a ventrally displaced mandibular joint (20); and the presence of more than 10 cervical (neck) vertebrae (21) (see Fig. 1 for a pictorial orientation of anatomical terms).

Figure 1. Schematic of the skull of the therizinosaur Erlikosaurus, in left lateral view of the upper jaw (A), left lateral view of the lower jaw (B), and dorsal view of the lower jaw (C), with anatomical terms used in this paper labeled. Based on a digital reconstruction of specimen IGM 100/111, provided in Lautenschlager et al., 2014.

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By documenting the distribution of these characters among theropods, Zanno and Makovicky inferred herbivory as the predominant diet in the ceratosaur Limusaurus and many clades within Maniraptoriformes (Ornithomimosauria, Therizinosauria, Alvarezsauria, Oviraptorosauria, Scansoriopterygidae, Avialae, and the troodontid Jinfengopteryx) (Zanno and Makovicky, 2011). Subsequently, the theropod Chilesaurus was described by Novas et al. in 2015 as a basal tetanuran that had adapted to a non-hypercarnivorous diet independently of the aforementioned groups (Fig. 2). Additionally, though modern birds have diversified to become specialized for a vast variety of feeding habits, herbivory has evolved several times in their history (Olsen, 2015). Because carnivory is the likely ancestral condition for theropods, herbivorous theropods almost certainly went through a trophic shift, or change in diet, over the course of their evolution (Zanno and Makovicky, 2011).

Figure 2. A phylogenetic tree of theropod dinosaurs, modified from results recovered by Novas et al., 2015. Green indicates lineages inferred to have been non-hypercarnivorous and red indicates lineages inferred to have been hypercarnivorous. Star symbols indicate inferred trophic shifts to non-hypercarnivory. The evolutionary drivers of these repeated trophic shifts and the ecological roles of herbivorous Mesozoic theropods are mysterious and have not been investigated in detail. The two non-theropod dinosaur groups (sauropodomorphs and ornithischians) are known to have become specialized for a herbivorous lifestyle prior to the appearance of any of the non- hypercarnivorous theropod lineages (Yates et al., 2010; Norman et al., 2011), suggesting that there were changes in at least some Mesozoic ecosystems that opened ecospace for theropods to radiate into non-hypercarnivorous niches. In this study I tested for possible correlations between the evolution of non- hypercarnivorous theropods and change in Mesozoic ecosystems over time, with the intent of providing a framework for future research in potential drivers of diversification in non- hypercarnivorous theropods.

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Method of Analysis Three working hypotheses were outlined focusing on different aspects of Mesozoic ecology that potentially drove theropod evolution: 1. Diversity of non-hypercarnivorous Mesozoic theropods was correlated with lower diversity of potential competitors. 2. Diversity of non-hypercarnivorous Mesozoic theropods was correlated with greater diversity of potential food sources. 3. Diversity of non-hypercarnivorous Mesozoic theropods was correlated with specific changes in environmental conditions. The experimental design of this study is aimed at overturning the null hypothesis, that the diversity of non-hypercarnivorous Mesozoic theropods was not correlated with any of the above factors. Although statistically significant correlation would not demonstrate said factors to have directly caused observed patterns of non-hypercarnivorous theropod diversity, it would be sufficient to overturn the null hypothesis and identify said factors as relevant points of consideration in hypothetical future extensions of this work. Conversely, lack of statistical support for correlation would suggest that said factors were not important in determining non- hypercarnivorous theropod diversity. Non-hypercarnivorous theropods represent a large component of theropod diversity and are known to have been common in some Mesozoic ecosystems, e.g.: the oviraptorosaur Caudipteryx is the second most abundant dinosaur (after the ceratopsian ornithischian Psittacosaurus) known from the Jianshangou Beds of the Yixian Formation in China (Xu and Norell, 2006). Understanding the ecological and environmental drivers of their evolution would be helpful in elucidating our knowledge of theropod history and paleoecology. Data provided by the Paleobiology Database (PBDB) (accessible at: https://paleobiodb.org/cgi-bin/bridge.pl) was used to conduct this research. The PBDB is a non- governmental, non-profit database documenting known occurrences and collections of fossil taxa worldwide, run and updated by a multidisciplinary, international team of paleontological researchers. Collection data can be searched and retrieved from the database using one or more parameters, including taxon name, geologic unit, and geologic age. To assess diversity of non-hypercarnivorous theropods throughout the Mesozoic, number of genera was used as a measure of diversity. In the absence of direct evidence for diet, inference of non-hypercarnivory in theropods was made using the criteria outlined by Zanno and Makovicky, 2011. (Phylogenetic bracketing was used to infer conditions of anatomical features not preserved in specific taxa.) The use of genera as opposed to species in these counts was intended to marginally simplify the process, but it is worth noting that the majority of Mesozoic dinosaur genera are monotypic, e.g.: among therizinosaurian theropods, only Nothronychus is known from more than one valid species (N. mckinleyi and N. graffami). As such, it is unlikely that use of species counts would have greatly altered the results found here. The same measures were conducted on the potential ecological competitors of non-hypercarnivorous theropods. These potential competitors were defined as other vertebrates inferred to have had predominantly herbivorous habits that were contemporaneous with non-hypercarnivorous theropods. Herbivore species were included regardless of difference in body size, despite the unlikelihood that herbivores of large size discrepancy would have competed for the exact same food sources. This decision was made in light of the fact that, as juveniles, even the largest dinosaurs would have

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been well within the size range of many non-hypercarnivorous theropods (Codron et al., 2012) and may have thus competed with them. Assessing diversity of potential theropod prey items was complicated by several factors. Plants and invertebrates have been suggested to be important food sources for non- hypercarnivorous theropods (Senter, 2005; Longrich and Currie, 2009; Zanno and Makovicky, 2011), but environmental conditions that preserve vertebrates (such as theropod dinosaurs) are not always conducive to the preservation of plants and invertebrates (Behrensmeyer et al., 2000). Only 4 (out of 51) geologic formations considered in this study preserved a substantial invertebrate fossil record, whereas only 15 preserved a substantial plant fossil record. Due to this small sample size, invertebrate diversity was not considered in this study. Problems with estimating plant diversity were additionally compounded by the fact that plant fossils are often preserved as disassociated body parts (e.g.: leaves, pollen, roots, etc.). Because it is difficult to evaluate whether these different body parts belong to the same biologic species of plant, each fossil plant body part is frequently given its own taxonomic system (Cleal and Thomas, 2010). Potentially, a single species of fossil plant can have a different binomial name for each of its body parts. For this reason, diversity of plants was counted at the “family” level in this study, rather than the genus or species level. Plant fossils that were not assigned to a specific “family” but were clearly distinct from other contemporaneous species were also included in the diversity count. To test for extrinsic environmental factors beyond biological interactions, change in global sea level was used as a proxy for global environmental change, following other studies on paleobiodiversity (e.g.: Mannion et al., 2011; Mannion et al., 2015). Global sea levels during the geologic ages examined were averaged from estimates by Miller et al., 2005. Measured diversity of non-hypercarnivorous theropods plotted against the diversity of their potential competitors and prey as well as average global sea level in regression analyses to test for possible correlation between these measures. Spearman's ρ and Kendall's τ were used as tests to assess statistical significance of correlation between diversity of different groups of organisms. Spearman's ρ compares the ordering of data points for two variables, whereas Kendall's τ measures the synchronicity of two data curves. These particular coefficients have been widely used evaluating abundance and diversity data (e.g.: Mannion et al., 2011; Brocklehurst et al., 2012), because such data cannot be assumed to follow any simple probability distribution and require non-parametric tests of correlation. Statistical calculations were made in the paleontological statistics software PAST (Hammer et al., 2001). If the diversity of non-hypercarnivorous theropods is shown to be negatively correlated with that of their potential competitors, this would support competitive displacement as a driver of non-hypercarnivorous theropod evolution. Although ecological competition happens at the individual level, the resolution of the fossil record is not sufficient for testing the presence of competition at such a fine scale. Instead, based on the prediction that competitive displacement will cause one lineage to decrease in diversity and abundance with the increase of those metrics of a competing lineage over time (Prevosti et al., 2013), long-term relative success of different lineages was used as a proxy to test for the presence of ecological competition between the different groups of herbivores. Conversely, diversity of contemporaneous plant species would be expected to correlate positively with non-hypercarnivorous theropod diversity if it was a notable driver of non-hypercarnivorous theropod evolution, as the increased diversity of plant species would be predicted to facilitate niche partitioning and diversification among herbivores. (However, observations of modern ecosystems, e.g. Hawkins and Porter, 2003, suggest that a

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direct causal relationship is not always present between plant and herbivore diversity; both instead being driven toward similar trends by extrinsic factors.) Lastly, any significant correlation between global sea level and non-hypercarnivorous theropod diversity would suggest associated global environmental conditions (such as changes in climate and available land area) as a potential driver of diversification (Mannion et al., 2011). The taxonomic revision of fossil taxa over time may influence these results. For example, in 2008, Benton estimated that 50% of Mesozoic dinosaur species named up to 2004 were later considered invalid. However, he also determined that researchers have had increasing success in coining valid taxa over time and that taxonomic revision usually does not drastically change the conclusions of research on relative diversity or broad-scale evolutionary trends within groups (Benton, 2008). The PBDB is generally up to date with current taxonomic revisions, e.g.: the dromaeosaurid theropod “Cryptovolans” is listed as a synonym of Microraptor (following Senter et al., 2004) and Piksi, formerly misinterpreted as an avialan theropod, is listed as a pterosaur (following Agnolin and Varricchio, 2012). Sampling is a significant contributor to bias in fossil collection, affecting observed paleodiversity (Butler et al., 2011). Mannion et al., 2011 used dinosaur-bearing formations (DBFs) and dinosaur-bearing collections (DBCs) as proxies for taphonomic and sampling bias. They related these proxies to known diversity of sauropodomorph dinosaurs by implementing residuals and rarefaction analysis, allowing for the identification of data points strongly impacted by these biases. The effects of sampling bias in this study were located following their residual method and these biases were corrected for by running analyses with the impacted data points removed.

Presentation of Data and Analysis of Uncertainty 1. Case study (demonstration of feasibility) To demonstrate feasibility of the proposed experimental procedure, a preliminary case study was conducted on a specific group of non-hypercarnivorous theropods present in a localized setting and time frame: investigating oviraptorosaur diversity in relation to that of their potential ecological competitors in the Cretaceous of Asia. The collection search form of the PBDB was used to identify oviraptorosaur-bearing geological formations, entering the search terms “Oviraptorosauria” for taxon name, “Cretaceous” for time interval, and “Asia” for country/continent as parameters. In addition, the database was independently searched for each named oviraptorosaur genus known from the Cretaceous of Asia to increase the likelihood that all relevant entries had been recovered. All recorded genera and occurrences of oviraptorosaurs and their associated formations were tabulated in an Excel spreadsheet. All genus counts were assigned a maximum and minimum estimate to account for specimens listed as unspecified or indeterminate genera in the database – maximum estimates assume that all such specimens represent their own genera, whereas minimum estimates assume that they belong to already- known genera. Once all oviraptorosaur-bearing formations in the database had been identified, each formation was searched independently with the collection search form and every fossil collection event recorded for each was scrutinized. All genera and occurrences of putative ecological competitors of oviraptorosaurs in each formation were entered into the spreadsheet (Appendix A). Although one genus of oviraptorosaur (Oviraptor) is known to have at least occasionally eaten smaller vertebrates (Zanno and Makovicky, 2011), ecological competitors were defined as

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contemporaneous terrestrial vertebrates inferred to have been predominantly herbivorous because this research is intended to specifically focus on the evolution of herbivory. In addition, some other oviraptorosaur species appear to have been more convincingly herbivorous (Xu et al., 2002). The final list of putative competitors tabulated included ornithischian and sauropod dinosaurs, multituberculate mammals (Wilson et al., 2012), polyglyphanodontian lizards (Evans and Manabe, 2008), tapejarid pterosaurs (Vullo et al., 2012), and other non-hypercarnivorous theropods (as inferred by Zanno and Makovicky, 2011). Most non-oviraptorosaur maniraptoriform theropods were included, with the exception of groups inferred to have been specialized hypercarnivores (e.g.: dromaeosaurids, Bohaiornis) (Fowler et al., 2011; Li et al., 2014) or piscivores (e.g.: Yanornis and hesperornithines) (Zheng et al., 2014, contra Zhou et al., 2004; Naish, 2014). Inference of carnivory was only made when corroborated by anatomical, phylogenetic, or ecological evidence. The presence of vertebrate prey as gut contents alone was not deemed sufficient to conclude a predominantly carnivorous diet, given that omnivory has been demonstrated in both living and fossil theropods (Lee et al., 2014; Naish, 2014). Most troodontids (with the exception of Jinfengopteryx) were excluded from this analysis despite the fact that they may have had an omnivorous diet (Holtz et al., 1998), because they were resolved as carnivorous or found to possess ambiguous evidence of adaptations for herbivory by Zanno and Makovicky, 2011, suggesting that troodontids were generally less specialized for herbivory than typical maniraptoriforms. Similarly, the basal maniraptoriform Fukuivenator was reported to possess some herbivory-related characters (Azuma et al., 2016), but not enough (< 6 characters) to be confidently inferred as primarily herbivorous under Zanno and Makovicky’s criteria. Geologic Geologic # Oviraptorosaur # Other Non- Total # Putative Formation Stage Genera (min.- hypercarnivorous Competitor max.) Theropod Genera (min.- Genera (min.- max.) max.) Nemegt Maastrichtian 5-13 7-15 14-54 Nanxiong Maastrichtian 5-6 1-1 3-3 Dalangshan Maastrichtian 1-1 0 0 Pingling Maastrichtian 1-1 0 3-3 Iren Dabasu Campanian 1-1 4-6 8-15 Barun Goyot Campanian 5-5 6-7 35-50 Djadochta Campanian 3-6 7-11 28-52 Bayan Campanian 1-1 0 5-6 Mandahu Wulansuhai Campanian 1-1 1-1 1-1 Bissekty Santonian 1-2 5-12 13-50 Dabrazhin Santonian 1-1 1-2 7-8 Mangchua Cenomanian 1-1 1-1 5-9 Qiupa Cenomanian 1-1 2-2 7-7 Shahai Aptian 1-1 0 6-7 Fuxin Aptian 1-1 0 5-7 Jiufotang Aptian 1-1 37-41 44-48 Yixian Aptian 4-4 24-27 32-37 Table 1. Genus counts of oviraptorosaurs and potential ecological competitors from the Cretaceous of Asia, sorted by geologic formation. Data were retrieved from the PBDB on from November 9-11, 2015.

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To visualize the raw data, scatter plots of oviraptorosaur diversity compared to that of potential competitors were created (Figs. 3-4) as well as raw diversity curves binned by geologic stages (Fig. 5). Values binned by geologic stages were modified to account for double-counting of species present in more than one formation. Statistically significant correlations between genus counts were tested by calculating Spearman's ρ and Kendall's τ coefficients relating oviraptorosaur diversity to that of potential competitors (Table 2). These results suggested statistically significant positive correlations between oviraptorosaur diversity and diversity of other non-hypercarnivorous theropods in the same time and region as well as between maximum estimates of oviraptorosaur diversity and maximum estimates of all putative competitor diversity in the same time and region. However, no statistically significant relationships were recovered when the data points were binned by geologic stage.

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Figure 4. Scatter plots relating number of oviraptorosaur genera to number of other contemporaneous non- hypercarnivorous theropod genera from the Cretaceous of Asia, reflecting minimum (above) and maximum (below) estimates of genus count.

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Figure 5. Measures of diversity collected in the case study plotted against geologic stages, reflecting minimum (above) and maximum (below) estimates of genus count.

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Spearman’s ρ Kendall’s τ Spearman’s ρ Kendall’s τ (data points (data points (data points (data points binned by binned by binned by stage) binned by formation) formation) stage) Oviraptorosaur 0.51 0.41 0.56 0.32 diversity vs. other (P = 0.036) (P = 0.057) (P = 0.32) (P = 0.61) herbivorous theropod diversity (min.) Oviraptorosaur 0.55 0.45 0.60 0.40 diversity vs. other (P = 0.023) (P = 0.034) (P = 0.29) (P = 0.46) herbivorous theropod diversity (max.) Oviraptorosaur 0.40 0.34 0.56 0.32 diversity vs. diversity (P = 0.11) (P = 0.11) (P = 0.32) (P = 0.61) of all putative competitors (min.) Oviraptorosaur 0.58 0.51 0.70 0.60 diversity vs. diversity (P = 0.015) (P = 0.013) (P = 0.19) (P = 0.22) of all putative competitors (max.) Table 2. Spearman’s ρ and Kendall’s τ coefficients relating different measures of diversity data collected in the case study. Values in bold are statistically significant.

To test for the impact of sampling biases on the raw data, residual values were calculated from DBCs following Mannion et al., 2011. By using the “download records” function of the PBDB and specifying the parameters “Dinosauria” for taxonomy, “Cretaceous” for time, and “Asia” for location (while excluding “India,” which was a separate subcontinent during the Cretaceous), a list was retrieved containing all the dinosaur-bearing fossil collections recovered at each formation that fit the given location and time frame. The number of collections was separated by bins corresponding to geologic stage. Log values were taken of the number of collections and previous measures of diversity of each bin. The log values of collection number and genus number were independently sorted from low to high and fit to a linear model of y = mx + c. This equation was used to derive a model of predicted diversity based on sampling. Residuals were calculated by taking the difference between values derived from the equation and log values of observed diversity. For almost all measures of diversity, residual values indicated that data taken from formations formed during the Santonian and Campanian were strongly affected by sampling bias (-0.2 < residual value < 0.2) (Figs. 6-8). Interestingly, the residuals predicted from use of maximum estimates of total competitor diversity suggested that the observed values of competitor diversity were universally lower than expected (Fig. 8). However, considering that it is unlikely every fragmentary and unidentified specimen represents a new genus (as assumed by the maximum diversity estimates), the validity of calculations based on maximum estimate values is doubtful.

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Figure 6. Residual diversity of oviraptorosaurs from the Cretaceous of Asia through time, calculated from number of DBCs and reflecting minimum (above) and maximum (below) estimates of genus count.

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Figure 7. Residual diversity of non-oviraptorosaur non-hypercarnivorous theropods from the Cretaceous of Asia through time, calculated from number of DBCs and reflecting minimum (above) and maximum (below) estimates of genus count.

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Figure 8. Residual diversity of all putative ecological competitors of oviraptorosaurs from the Cretaceous of Asia through time, calculated from number of DBCs and reflecting minimum (above) and maximum (below) estimates of genus count.

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After omitting data from Campanian- and Santonian-aged formations, correlation coefficients were recalculated using only the minimum diversity estimates (Table 3). Spearman’s ρ Kendall’s τ Spearman’s ρ Kendall’s τ (data points (data points (data points (data points binned by binned by binned by stage) binned by formation) formation) stage) Oviraptorosaur 0.511 0.41 0.60 (P = 0.23) 0.33 diversity vs. other (P = 0.036) (P = 0.057) (P = 1) herbivorous theropod diversity (min.) Oviraptorosaur 0.40 0.34 0.70 (P = 0.23) 0.33 diversity vs. diversity (P = 0.11) (P = 0.11) (P = 1) of all putative competitors (min.) Table 3. Spearman’s ρ and Kendall’s τ coefficients relating different measures of diversity data collected in the case study, after removal of data impacted by sampling bias. Values in bold are statistically significant.

2. Expanded dataset of herbivorous taxa After demonstration of experimental feasibility, records of all non-hypercarnivorous Mesozoic theropods known (as of February 2016) that had not been included in the case study were retrieved from the PBDB and added to the dataset. Once again, collection records for geologic formations containing non-hypercarnivorous theropods were retrieved and occurrences of potential competitor genera were recorded (Appendix B). In addition to the competitor groups listed previously, the expanded dataset also includes tritylodontid (Reed et al., 2016) and haramiyid (Luo et al., 2015) mammaliamorphs, opisthodontian sphenodontians (Martínez et al., 2013), and the notosuchian crocodylomorph Notosuchus (Fiorelli and Calvo, 2008). Given that the preliminary research established the unreliability of maximum taxonomic diversity estimates for the purposes of this study, only values of minimum diversity estimates were used in analysis of the expanded dataset. Both the theropods and their putative competitors were categorized into subgroups based on phylogeny to facilitate testing for the possibility of differing correlations between more specific groups of organisms. The complete dataset contains records of over 500 taxa from 51 geologic formations, spanning in geologic time from the Late Jurassic Oxfordian Age to the Late Cretaceous Maastrichtian Age (Fig. 9).

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Figure 9. Complete dataset of non-hypercarnivorous theropod and putative competitor diversity plotted against time. DBCs and DBFs for the analyzed geographic and temporal range were downloaded from the PBDB by specifying the parameters “Dinosauria” for taxonomy, “Late Jurassic-Late Cretaceous” for time, and “North America,” “South America,” “Africa,” “Europe,” and “Asia” for location (while excluding “India,” which was a separate subcontinent during the Late Jurassic and Cretaceous). Residual diversity for theropods and their competitors were calculated based on both DBCs and DBFs using the same methods described previously. The resulting residual values indicated that observed non-hypercarnivorous theropod diversity was impacted most strongly by sampling biases in records from the Campanian, Barremian, and Oxfordian (Fig. 10) and by preservational biases in records from the Maastrichtian, Campanian, and Oxfordian (Fig. 11). Observed diversity of potential competitors was impacted most strongly by sampling biases in records from the Campanian, Cenomanian, and Aptian (Fig. 12) and by preservational biases in records from the Maastrichtian, Aptian, and Oxfordian (Fig. 13).

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Figure 13. Residual diversity of all putative ecological competitors of non-hypercarnivorous theropods through time, calculated from number of DBFs.

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Removal of all of the data points impacted by these biases resulted in a much reduced dataset of 107 taxa. Thus, in an effort to preserve a large sample size, not all of these data points were removed for the following analysis. However, data from Oxfordian- and Campanian-aged formations were omitted, as records from these two geologic stages were identified most frequently as impacted data points across all measures of potential bias. After removal of these data points, correlation coefficients were calculated between total non-hypercarnivorous theropod diversity, total competitor diversity, the different theropod subgroups, and the different competitor subgroups using the same methods described previously. When binned by formation, significant positive correlation was consistently recovered for associations between total theropod diversity and total competitor diversity; ornithomimosaur diversity and total competitor diversity, ankylosaur diversity, ceratopsian diversity, iguanodontian diversity, and pachycephalosaur diversity; and oviraptorosaur diversity and total competitor diversity and mammaliamorph diversity. When binned by geologic stage, significant positive correlation was consistently recovered for associations between total theropod diversity and total competitor diversity; ornithomimosaur diversity and total competitor diversity, oviraptorosaur diversity, ankylosaur diversity, ceratopsian diversity, iguanodontian diversity, mammaliamorph diversity, and sauropod diversity; oviraptorosaur diversity and total competitor diversity, ankylosaur diversity, ceratopsian diversity, mammaliamorph diversity, sauropod diversity, and squamate diversity; and therizinosaur diversity and ankylosaur diversity, ceratopsian diversity, iguanodontian diversity, and mammaliamorph diversity (Table 4). Spearman’s ρ Kendall’s τ (data Spearman’s ρ Kendall’s τ (data (data points points binned by (data points points binned by binned by formation) binned by stage) stage) formation) Total theropod 0.38 0.29 0.66 0.56 diversity vs. total (P = 0.024) (P = 0.014) (P = 0.028) (P = 0.017) competitor diversity Alvarezsaur 0.078 -0.009 0.44 0.38 diversity vs. total (P = 0.66) (P = 0.94) (P = 0.17) (P = 0.10) competitor diversity Alvarezsaur 0.15 0.14 0.44 0.13 diversity vs. (P = 0.38) (P = 0.23) (P = 0.76) (P = 0.59) avialan diversity Alvarezsaur -0.16 -0.15 0.93 0.50 diversity vs. (P = 0.36) (P = 0.20) (P = 0.070) (P = 0.032) ornithomimosaur diversity Alvarezsaur -0.32 -0.30 0.88 0.35 diversity vs. (P = 0.064) (P = 0.013) (P = 0.21) (P = 0.14) oviraptorosaur diversity Alvarezsaur -0.035 -0.034 0.61 -0.082 diversity vs. (P = 0.84) (P = 0.77) (P = 0.77) (P = 0.73) therizinosaur

22 diversity Alvarezsaur -0.14 -0.13 0.93 0.21 diversity vs. (P = 0.41) (P = 0.26) (P = 0.45) (P = 0.37) ankylosaur diversity Alvarezsaur -0.079 -0.074 0.86 0.38 diversity vs. (P = 0.65) (P = 0.53) (P = 0.17) (P = 0.10) ceratopsian diversity Alvarezsaur -0.078 -0.074 0.90 0.33 diversity vs. (P = 0.66) (P = 0.53) (P = 0.23) (P = 0.16) iguanodontian diversity Alvarezsaur -0.17 -0.16 0.84 0.084 diversity vs. (P = 0.32) (P = 0.18) (P = 0.79) (P = 0.72) mammaliamorph diversity Alvarezsaur 0.059 0.058 0.50 0.44 diversity vs. (P = 0.74) (P = 0.63) (P = 0.15) (P = 0.059) pachycephalosaur diversity Alvarezsaur 0.18 0.16 0.79 0.43 diversity vs. (P = 0.30) (P = 0.18) (P = 0.086) (P = 0.065) sauropod diversity Alvarezsaur 0.059 0.058 0.58 0.24 diversity vs. (P = 0.74) (P = 0.63) (P = 0.39) (P = 0.30) squamate diversity Avialan diversity 0.22 0.75 0.44 0.36 vs. total (P = 0.20) (P = 1.9×10-10) (P = 0.17) (P = 0.13) competitor diversity Avialan diversity 0.21 0.19 0.48 0.42 vs. (P = 0.23) (P = 0.11) (P = 0.13) (P = 0.075) ornithomimosaur diversity Avialan diversity 0.23 0.21 0.55 0.47 vs. (P = 0.18) (P = 0.082) (P = 0.077) (P = 0.045) oviraptorosaur diversity Avialan diversity 0.024 0.024 0.45 0.41 vs. therizinosaur (P = 0.89) (P = 0.84) (P = 0.16) (P = 0.082) diversity Avialan diversity -0.007 -0.008 0.41 0.33 vs. ankylosaur (P = 0.97) (P = 0.95) (P = 0.21) (P = 0.16)

23 diversity Avialan diversity 0.17 0.15 0.52 0.45 vs. ceratopsian (P = 0.34) (P = 0.22) (P = 0.099) (P = 0.054) diversity Avialan diversity 0.16 0.15 0.51 0.42 vs. (P = 0.35) (P = 0.21) (P = 0.11) (P = 0.074) mammaliamorph diversity Avialan diversity 0.14 0.12 0.43 0.37 vs. iguanodontian (P = 0.43) (P = 0.32) (P = 0.19) (P = 0.11) diversity Avialan diversity 0.13 0.12 0.31 0.27 vs. (P = 0.44) (P = 0.30) (P = 0.36) (P = 0.24) pachycephalosaur diversity Avialan diversity -0.045 -0.040 0.15 0.13 vs. sauropod (P = 0.80) (P = 0.74) (P = 0.66) (P = 0.59) diversity Avialan diversity 0.029 0.027 0.11 0.10 vs. squamate (P = 0.87) (P = 0.82) (P = 0.76) (P = 0.67) diversity Ornithomimosaur 0.35 0.31 0.93 0.86 diversity vs. total (P = 0.037) (P = 0.0002) (P = 0.00003) (P = 0.0002) competitor diversity Ornithomimosaur 0.26 0.24 0.88 0.82 diversity vs. (P = 0.14) (P = 0.040) (P = 0.0004) (P = 0.0005) oviraptorosaur diversity Ornithomimosaur 0.14 0.13 0.47 0.40 diversity vs. (P = 0.42) (P = 0.28) (P = 0.15) (P = 0.087) therizinosaur diversity Ornithomimosaur 0.55 0.49 0.87 0.77 diversity vs. (P = 0.0006) (P = 0.00004) (P = 0.0006) (P = 0.0009) ankylosaur diversity Ornithomimosaur 0.46 0.41 0.74 0.70 diversity vs. (P = 0.006) (P = 0.0005) (P = 0.010) (P = 0.003) ceratopsian diversity Ornithomimosaur 0.38 0.34 0.78 0.72 diversity vs. (P = 0.024) (P = 0.004) (P = 0.004) (P = 0.002) iguanodontian diversity Ornithomimosaur 0.31 0.27 0.74 0.69

24 diversity vs. (P = 0.068) (P = 0.021) (P = 0.009) (P = 0.003) mammaliamorph diversity Ornithomimosaur 0.51 0.47 0.54 0.51 diversity vs. (P = 0.002) (P = 0.00006) (P = 0.088) (P = 0.030) pachycephalosaur diversity Ornithomimosaur 0.048 0.040 0.91 0.84 diversity vs. (P = 0.78) (P = 0.73) (P = 0.0001) (P = 0.0003) sauropod diversity Ornithomimosaur -0.0009 0 0.57 0.50 diversity vs. (P = 0.10) (P = 1) (P = 0.070) (P = 0.032) squamate diversity Oviraptorosaur 0.34 0.43 0.88 0.76 diversity vs. total (P = 0.047) (P = 0.008) (P = 0.0003) (P = 0.001) competitor diversity Oviraptorosaur 0.19 0.18 0.52 0.43 diversity vs. (P = 0.26) (P = 0.14) (P = 0.10) (P = 0.063) therizinosaur diversity Oviraptorosaur 0.30 0.27 0.90 0.84 diversity vs. (P = 0.08) (P = 0.023) (P = 0.0002) (P = 0.0003) ankylosaur diversity Oviraptorosaur 0.32 0.30 0.71 0.65 diversity vs. (P = 0.059) (P = 0.012) (P = 0.015) (P = 0.005) ceratopsian diversity Oviraptorosaur 0.21 0.19 0.68 0.58 diversity vs. (P = 0.22) (P = 0.11) (P = 0.021) (P = 0.013) iguanodontian diversity Oviraptorosaur 0.35 0.32 0.86 0.79 diversity vs. (P = 0.037) (P = 0.006) (P = 0.0006) (P = 0.0007) mammaliamorph diversity Oviraptorosaur 0.20 0.18 0.53 0.49 diversity vs. (P = 0.26) (P = 0.13) (P = 0.094) (P = 0.037) pachycephalosaur diversity Oviraptorosaur 0.043 0.041 0.76 0.65 diversity vs. (P = 0.81) (P = 0.73) (P = 0.006) (P = 0.005) sauropod

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diversity Oviraptorosaur 0.080 0.075 0.67 0.62 diversity vs. (P = 0.65) (P = 0.53) (P = 0.024) (P = 0.008) squamate diversity Therizinosaur -0.042 0.20 0.61 0.45 diversity vs. total (P = 0.81) (P = 0.096) (P = 0.048) (P = 0.054) competitor diversity Therizinosaur 0.098 0.090 0.61 0.47 diversity vs. (P = 0.58) (P = 0.45) (P = 0.044) (P = 0.037) ankylosaur diversity Therizinosaur 0.13 0.13 0.70 0.63 diversity vs. (P = 0.46) (P = 0.29) (P = 0.017) (P = 0.007) ceratopsian diversity Therizinosaur 0.14 0.13 0.68 0.59 diversity vs. (P = 0.43) (P = 0.28) (P = 0.022) (P = 0.012) iguanodontian diversity Therizinosaur 0.0007 0.004 0.72 0.60 diversity vs. (P = 1) (P = 0.98) (P = 0.012) (P = 0.010) mammaliamorph diversity Therizinosaur -0.082 -0.079 0.37 0.35 diversity vs. (P = 0.64) (P = 0.50) (P = 0.26) (P = 0.14) pachycephalosaur diversity Therizinosaur 0.13 0.13 0.27 0.21 diversity vs. (P = 0.44) (P = 0.29) (P = 0.43) (P = 0.38) sauropod diversity Therizinosaur 0.29 0.28 0.23 0.22 diversity vs. (P = 0.096) (P = 0.019) (P = 0.50) (P = 0.35) squamate diversity Table 4. Spearman’s ρ and Kendall’s τ coefficients relating different measures of diversity data collected for the expanded dataset in this study, after removal of data impacted by sampling and preservational bias. Values in bold are statistically significant.

3. Testing for correlation with plant diversity Plant diversity observed in the previously considered formations was measured using the PBDB. However, only 15 formations representing 7 geologic stages were recorded to preserve identifiable plant specimens (Appendix C). When data points representing Campanian- and

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Oxfordian-aged fossils were removed, the remaining dataset was too small to reliably analyze. Correlation coefficients between plant diversity and non-hypercarnivorous theropod diversity were recalculated using the complete plant dataset and data points representing contemporaneous theropods, binned only by geologic formation. No statistically significant correlations were found (Table 5). Spearman’s ρ Kendall’s τ Total theropod diversity vs. 0.18 0.14 total plant diversity (P = 0.51) (P = 0.47) Alvarezsaur diversity vs. plant 0.19 0.16 diversity (P = 0.50) (P = 0.40) Avialan diversity vs. plant -0.003 0 diversity (P = 0.99) (P = 1) Ornithomimosaur diversity vs. 0.15 0.13 plant diversity (P = 0.60) (P = 0.51) Oviraptorosaur diversity vs. 0.23 0.20 plant diversity (P = 0.42) (P = 0.29) Therizinosaur diversity vs. 0.30 0.26 plant diversity (P = 0.28) (P = 0.17) Table 5. Spearman’s ρ and Kendall’s τ coefficients relating theropod and plant diversity when binned by geologic formation.

4. Testing for correlation with average global sea level Correlation coefficients were calculated between average global sea level (Appendix D) and theropod diversity, binned by geologic stage. (Campanian- and Oxfordian-aged data points were removed.) Only the diversity of alvarezsaurs and, to a lesser extent, oviraptorosaurs were found to be significantly positively correlated with average global sea level (Table 6). Spearman’s ρ Kendall’s τ Total theropod diversity vs. 0.22 0.21 average global sea level (P = 0.52) (P = 0.37) Alvarezsaur diversity vs. 0.78 0.57 average global sea level (P = 0.005) (P = 0.012) Avialan diversity vs. average 0.065 0.078 global seal level (P = 0.85) (P = 0.74) Ornithomimosaur diversity vs. 0.58 0.45 average global sea level (P = 0.060) (P = 0.052) Oviraptorosaur diversity vs. 0.58 0.46 average global sea level (P = 0.063) (P = 0.050) Therizinosaur diversity vs. 0.21 0.15 average global sea level (P = 0.53) (P = 0.53) Table 6. Spearman’s ρ and Kendall’s τ coefficients relating theropod diversity and average global sea level when binned by geologic stage. Values in bold are statistically significant.

5. Discussion of uncertainty

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Though the residual method used in this study to account for bias has been widely used in studies of paleobiodiversity, it is not the only such method that can be used for this purpose (Mannion et al., 2011). It has even been argued that the residual method as used here is overly simplistic and that more complex modifications to it can better estimate biases present in observed taxonomic diversity (Lloyd, 2012). However, considering that no study has previously been conducted on the specific subject matter of this paper (association between diversity of non-hypercarnivorous theropods and contemporary ecological factors), the research presented here is intended to be foundational in nature, hence the decision to opt for a more conventional and simplified procedure. Hypothetical future extensions of this research should keep in mind the ongoing debates about the adequacy of different methods for evaluating diversity in the fossil record and refine the experimental methods accordingly. In addition, this study was unable to entirely remove all data points identified as being strongly affected by biasing factors without greatly reducing sample size. Thus, the results presented here can only be considered a best approximation given the available methods and data. This conundrum can likely only be resolved through the development of more complex experimental procedures or a large increase in available data.

Discussion The results support a statistically significant positive correlation between non-hypercarnivorous theropod diversity and diversity of other herbivores through both time and space. As such, the null hypothesis that non-hypercarnivorous theropod diversity is entirely independent of putative ecological competitors is rejected based on these data. However, these results do not support the prediction that increased diversity of non-hypercarnivorous theropods is correlated with decreased diversity of putative competitors, given that almost no significant negative correlations between theropod diversity and potential competitor diversity were recovered. This suggests that non-hypercarnivorous theropods were not in direct competition with other herbivorous vertebrates, possibly due to partitioning of herbivorous niches or by taking advantage of non- plant food sources. It is possible that, instead of competing with other herbivorous vertebrates, at least some non-hypercarnivorous theropods somehow benefited from their presence. Large herbivores in modern times and recent prehistory are known to radically change their environment as ecosystem engineers (Barnosky et al., 2016), providing conditions conducive to survival of other organisms. Large dinosaurian herbivores of the Mesozoic may have performed similar roles. Given that some non-hypercarnivorous theropods are known to have eaten small vertebrates despite lacking adaptations for macropredation, another possibility is that some small-bodied herbivores (such as mammals, squamates, and juvenile dinosaurs) were an additional food source for these theropods. Yet another potential benefit non-hypercarnivorous theropods may have gained from coexisting with other herbivores was the increase in prey base for hypercarnivorous theropods resulting from the increased total herbivore diversity, preventing predation pressure from being concentrated on non-hypercarnivorous theropods. Lacking the means to directly observe prehistoric ecosystems, it would be difficult to determine which, if any, of these possibilities best explain the observed data. The patterns seen in this study may not necessarily result from zoological interactions. Similar environmental conditions favoring overall herbivore diversity, non-hypercarnivorous theropods included, would also produce the positive correlations recovered here. Change in global sea level, used as a proxy for global environmental change, was only found to correlate

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with a couple of specific theropod subgroups, suggesting that non-hypercarnivorous Mesozoic theropod diversity as a whole did not directly relate to conditions associated with global sea level. However, average global sea level can only approximate geographically and temporally broad- scale changes; factors more specific to individual ecosystems would be required to completely decouple the effects of zoological and environmental drivers of diversity. Plant diversity could potentially be used to infer such localized environmental conditions, but difficulties in accurately estimating plant diversity from the fossil record meant that this study was unable to reliably do so. The diversity of some specific subgroups of theropods (such as ornithomimosaurs and oviraptorosaurs) was found to be particularly strongly correlated with the diversity of contemporaneous herbivores, whereas the diversity of other theropod clades (such as avialans and alvarezsaurs) had nearly no correlation with the latter. Interestingly, avialans and alvarezsaurs may have been less dedicated to herbivory than other non-hypercarnivorous theropods. Alvarezsaurs possess anatomical features that have been interpreted as evidence of an insectivorous lifestyle (Senter, 2005; Longrich and Currie, 2009), whereas Mesozoic avialans do include species that preserve direct evidence of herbivory, but the group as a whole exhibits a diverse range of skull morphologies whose functional and dietary implications are poorly studied (O’Connor and Chiappe, 2011). For the purposes of this study, most Mesozoic avialans were assumed to be non-hypercarnivorous based on phylogenetic bracketing, but it is likely that their dietary habits were less uniform than assumed here. If alvarezsaurs and avialans were indeed less herbivorous on average than other non-hypercarnivorous theropods, they may have been subject to significantly different selective pressures from those other theropods and thus would not be expected to display the same ecological correlations. Indeed, alvarezsaurs were the only theropod subgroup considered whose diversity was consistently and significantly correlated with average global sea level, providing additional evidence that they experienced different evolutionary drivers.

Suggestions for Future Work The correlations tested in this study relied on raw diversity data without considering ghost lineages (inferred lineages of organisms unpreserved in the fossil record). Rerunning the analyses done in this study based on construction of phylogenetic diversity curves that can account for ghost lineages could potentially reveal more information pertinent to the question at hand, as well as provide an independent test of whether the correlations found here reflect real ecological trends. In addition to diversity, abundance (e.g.: number of specimens) could also be a useful measure of the relative ecological success of organisms. However, my experience in conducting this research shows that, though the PBDB contains detailed and up-to-date information on taxon diversity (e.g.: including data on all named oviraptorosaur genera as of the time of writing), it frequently lacks data on taxon abundance (e.g.: lacking records of specimens of the ornithomimosaur Deinocheirus described in Lee et al., 2014). Even in the technical literature, the exact abundances of many fossil taxa are not always recorded, preventing this study from exploring the topic of taxon abundance. Assessing relative abundance of the organisms considered here will almost certainly require visits to museum collections and detailed stratigraphic records. This study primarily tested for correlation between the diversity of non-hypercarnivorous theropods and biotic factors in their environment, with only global sea level used an abiotic

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proxy for environmental change. One line of inquiry that could supplement this research would be to consider the effects of additional abiotic environmental factors. Recent studies such as Butler and Barrett, 2008; Lyson and Longrich, 2011; Sales et al., 2016; and Arbour et al., in press have used chi-squared tests to evaluate whether specific habitats (e.g.: terrestrial, coastal, or marine) were favored by certain dinosaur groups. Similarly, Mannion et al., 2015 correlated diversity of pseudosuchian reptiles to estimated paleotemperature through time by using generalized least squares regression models. The experimental procedures of these papers could likely be adapted to study environmental and climatic preferences of non-hypercarnivorous theropods as well.

Conclusions The diversification of non-hypercarnivorous theropods during the Mesozoic remains an understudied subject in dinosaur paleontology, despite being of interest in understanding theropod evolution and Mesozoic ecosystems. The results of this study suggest that the diversity at least some groups of non-hypercarnivorous theropods was associated with increased diversity in other contemporaneous herbivores. Future extensions of this work should focus on decoupling biotic and abiotic factors that have potentially influenced the observed pattern as well as refining methods used to eliminate bias in studies of paleobiodiversity. The methods used in this study could also be applied to research on drivers of evolutionary change in other organisms.

Acknowledgements I would like to thank my advisor, Dr. Thomas Holtz, for his guidance throughout this project. Drs. Philip Candela, John Merck, Karen Prestegaard, and other faculty members of the University of Maryland Geology Department offered useful comments that improved this study’s experimental design. John Alroy, Anna Behrensmeyer, Richard Butler, Matthew Carrano, Roger Benson, Kirk Johnson, Philip Mannion, and Jonathan Tennant contributed data to the PBDB that were used in this research.

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Appendix A: Taxon Occurrence Data Used in Case Study

Formation Geologic stage Genus Category Barun Goyot Campanian Ankylosauria incertae Competitor sedis (2 specimens) (ankylosaur) Barun Goyot Campanian Pinacosaurus Competitor (ankylosaur) Barun Goyot Campanian Saichania Competitor (ankylosaur) Barun Goyot Campanian Tarchia Competitor (ankylosaur) Barun Goyot Campanian Bagaceratops Competitor (ceratopsian) Barun Goyot Campanian Gobiceratops Competitor (ceratopsian) Barun Goyot Campanian Platyceratops Competitor (ceratopsian) Barun Goyot Campanian Protoceratops Competitor (ceratopsian) Barun Goyot Campanian Protoceratopsidae incertae Competitor sedis (6 specimens) (ceratopsian) Barun Goyot Campanian Udanoceratops Competitor (ceratopsian) Barun Goyot Campanian Hadrosauridae incertae Competitor sedis (1 specimen) (iguanodontian) Barun Goyot Campanian Catopsbaatar Competitor (mammaliamorph) Barun Goyot Campanian Chulsanbaatar Competitor (mammaliamorph) Barun Goyot Campanian Multituberculata incertae Competitor sedis (3 specimens) (mammaliamorph) Barun Goyot Campanian Nemegtbaatar Competitor (mammaliamorph) Barun Goyot Campanian Nessovbaatar Competitor (mammaliamorph) Barun Goyot Campanian Tylocephale Competitor (pachycephalosaur) Barun Goyot Campanian Quaesitosaurus Competitor (sauropod) Barun Goyot Campanian Sauropoda incertae sedis Competitor (sauropod) (2 specimens) Barun Goyot Campanian Adamisaurus Competitor (squamate) Barun Goyot Campanian Altanteius Competitor (squamate) Barun Goyot Campanian Barungoia Competitor (squamate) Barun Goyot Campanian Cherminsaurus Competitor (squamate) Barun Goyot Campanian Darchansaurus Competitor (squamate) Barun Goyot Campanian Erdenetesaurus Competitor (squamate)

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Barun Goyot Campanian Gobinatus Competitor (squamate) Barun Goyot Campanian Gurvansaurus Competitor (squamate) Barun Goyot Campanian Macrocephalosauridae Competitor (squamate) incertae sedis (1 specimen) Barun Goyot Campanian Macrocephalosaurus Competitor (squamate) Barun Goyot Campanian Mongolochamops Competitor (squamate) Barun Goyot Campanian Parameiva Competitor (squamate) Barun Goyot Campanian Prodenteia Competitor (squamate) Barun Goyot Campanian Pyramicephalosaurus Competitor (squamate) Barun Goyot Campanian Tchingisaurus Competitor (squamate) Barun Goyot Campanian Alvarezsauridae incertae Theropod (alvarezsaur) sedis (1 specimen) Barun Goyot Campanian Ceratonykus Theropod (alvarezsaur) Barun Goyot Campanian Parvicursor Theropod (alvarezsaur) Barun Goyot Campanian Gobipipus Theropod (avialan) Barun Goyot Campanian Gobipteryx Theropod (avialan) Barun Goyot Campanian Hollanda Theropod (avialan) Barun Goyot Campanian Gallimimus Theropod (ornithomimosaur) Barun Goyot Campanian Ajancingenia Theropod (oviraptorosaur) Barun Goyot Campanian Avimimus Theropod (oviraptorosaur) Barun Goyot Campanian Conchoraptor Theropod (oviraptorosaur) Barun Goyot Campanian Nemegtomaia Theropod (oviraptorosaur) Barun Goyot Campanian Oviraptor Theropod (oviraptorosaur) Bayan Mandahu Campanian Pinacosaurus Competitor (ankylosaur) Bayan Mandahu Campanian Magnirostris Competitor (ceratopsian) Bayan Mandahu Campanian Protoceratops Competitor (ceratopsian) Bayan Mandahu Campanian Protoceratopsidae incertae Competitor sedis (1 specimen) (ceratopsian) Bayan Mandahu Campanian Kryptobaatar Competitor (mammaliamorph) Bayan Mandahu Campanian Bagaceratops Competitor (ornithischian) Bayan Mandahu Campanian Machairasaurus Theropod (oviraptorosaur) Bayan Mandahu Campanian Oviraptorosauria incertae Theropod

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sedis (1 specimen) (oviraptorosaur) Bissekty Santonian Ankylosauria incertae Competitor sedis (7 specimens) (ankylosaur) Bissekty Santonian Bissektipelta Competitor (ankylosaur) Bissekty Santonian Ceratopsia incertae sedis Competitor (2 specimens) (ceratopsian) Bissekty Santonian Turanoceratops Competitor (ceratopsian) Bissekty Santonian Cionodon Competitor (iguanodontian) Bissekty Santonian Gilmoreosaurus Competitor (iguanodontian) Bissekty Santonian Hadrosauridae incertae Competitor sedis (10 specimens) (iguanodontian) Bissekty Santonian Levnesovia Competitor (iguanodontian) Bissekty Santonian Uzbekbaatar Competitor (mammaliamorph) Bissekty Santonian Ornithischia incertae sedis Competitor (other) (6 specimens) Bissekty Santonian Ornithopoda incertae sedis Competitor (other) (3 specimens) Bissekty Santonian Sauropoda incertae sedis Competitor (sauropod) (3 specimens) Bissekty Santonian Buckantaus Competitor (squamate) Bissekty Santonian Avialae incertae sedis (2 Theropod (avialan) specimens) Bissekty Santonian Kuszholia Theropod (avialan) Bissekty Santonian Sazavis Theropod (avialan) Bissekty Santonian Zhyraornis Theropod (avialan) Bissekty Santonian Archaeornithomimus Theropod (ornithomimosaur) Bissekty Santonian Ornithomimosauria Theropod incertae sedis (1 (ornithomimosaur) specimen) Bissekty Santonian Caenagnathasia Theropod (oviraptorosaur) Bissekty Santonian Oviraptorosauria incertae Theropod sedis (1 specimen) (oviraptorosaur) Bissekty Santonian Therizinosauria incertae Theropod sedis (5 specimens) (therizinosaur) Dabrazhin Santonian Nodosauridae incertae Competitor sedis (1 specimen) (ankylosaur) Dabrazhin Santonian Ceratopsia incertae sedis Competitor (1 specimen) (ceratopsian)

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Dabrazhin Santonian Bactrosaurus Competitor (iguanodontian) Dabrazhin Santonian Jaxartosaurus Competitor (iguanodontian) Dabrazhin Santonian Kazaklambia Competitor (iguanodontian) Dabrazhin Santonian Sauropoda incertae sedis Competitor (sauropod) (1 specimen) Dabrazhin Santonian Archaeornithomimus Theropod (ornithomimosaur) Dabrazhin Santonian Ornithomimosauria Theropod incertae sedis (1 (ornithomimosaur) specimen) Dabrazhin Santonian Oviraptor Theropod (oviraptorosaur) Dalangshan Santonian Heyuannia Theropod (oviraptorosaur) Djadokhta Campanian Ankylosauria incertae Competitor sedis (9 specimens) (ankylosaur) Djadokhta Campanian Pinacosaurus Competitor (ankylosaur) Djadokhta Campanian Bagaceratops Competitor (ceratopsian) Djadokhta Campanian Protoceratopsidae incertae Competitor sedis (3 specimens) (ceratopsian) Djadokhta Campanian Udanoceratops Competitor (ceratopsian) Djadokhta Campanian Hadrosauridae incertae Competitor sedis (2 specimens) (iguanodontian) Djadokhta Campanian Protoceratops Competitor (iguanodontian) Djadokhta Campanian Allotheria incertae sedis Competitor (6 specimens) (mammaliamorph) Djadokhta Campanian Bulganbaatar Competitor (mammaliamorph) Djadokhta Campanian Catopsbaatar Competitor (mammaliamorph) Djadokhta Campanian Chulsanbaatar Competitor (mammaliamorph) Djadokhta Campanian Djadochtatherium Competitor (mammaliamorph) Djadokhta Campanian Kamptobaatar Competitor (mammaliamorph) Djadokhta Campanian Kryptobaatar Competitor (mammaliamorph) Djadokhta Campanian Nemegtobaatar Competitor

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(mammaliamorph) Djadokhta Campanian Sloanbaatar Competitor (mammaliamorph) Djadokhta Campanian Tchingisaurus Competitor (mammaliamorph) Djadokhta Campanian Tombaatar Competitor (mammaliamorph) Djadokhta Campanian Sauropoda incertae sedis Competitor (sauropod) (1 specimen) Djadokhta Campanian Adamisaurus Competitor (squamate) Djadokhta Campanian Dzhadochtosaurus Competitor (squamate) Djadokhta Campanian Gilmoreteius Competitor (squamate) Djadokhta Campanian Gobinatus Competitor (squamate) Djadokhta Campanian Gurvansaurus Competitor (squamate) Djadokhta Campanian Sineoamphibaena Competitor (squamate) Djadokhta Campanian Kol Theropod (alvarezsaur) Djadokhta Campanian Mononykus Theropod (alvarezsaur) Djadokhta Campanian Shuvuuia Theropod (alvarezsaur) Djadokhta Campanian Apsaravis Theropod (avialan) Djadokhta Campanian Avialae incertae sedis (1 Theropod (avialan) specimen) Djadokhta Campanian Elsornis Theropod (avialan) Djadokhta Campanian Gobipteryx Theropod (avialan) Djadokhta Campanian Ornithomimosauria Theropod incertae sedis (4 (ornithomimosaur) specimens) Djadokhta Campanian Citipati Theropod (oviraptorosaur) Djadokhta Campanian Khaan Theropod (oviraptorosaur) Djadokhta Campanian Oviraptor Theropod (oviraptorosaur) Djadokhta Campanian Oviraptorosauria incertae Theropod sedis (3 specimens) (oviraptorosaur) Fuxin Aptian Ankylosauria incertae Competitor sedis (3 specimens) (ankylosaur) Fuxin Aptian Heishanobaatar Competitor (mammaliamorph) Fuxin Aptian Liaobaatar Competitor (mammaliamorph) Fuxin Aptian Multituberculata incertae Competitor sedis (1 specimen) (mammaliamorph) Fuxin Aptian Sinobaatar Competitor (mammaliamorph) Fuxin Aptian Incisivosaurus Theropod

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(oviraptorosaur) Iren Dabasu Campanian Ankylosauria incertae Competitor sedis (1 specimen) (ankylosaur) Iren Dabasu Campanian Bactrosaurus Competitor (iguanodontian) Iren Dabasu Campanian Gilmoreosaurus Competitor (iguanodontian) Iren Dabasu Campanian Hadrosauridae incertae Competitor sedis (1 specimen) (iguanodontian) Iren Dabasu Campanian Ornithischia incertae sedis Competitor (other) (1 specimen) Iren Dabasu Campanian Sauropoda incertae sedis Competitor (sauropod) (3 specimens) Iren Dabasu Campanian Sonidosaurus Competitor (sauropod) Iren Dabasu Campanian Archaeornithomimus Theropod (ornithomimosaur) Iren Dabasu Campanian Ornithomimosauria Theropod incertae sedis (2 (ornithomimosaur) specimens) Iren Dabasu Campanian Gigantoraptor Theropod (oviraptorosaur) Iren Dabasu Campanian Erliansaurus Theropod (therizinosaur) Iren Dabasu Campanian Neimongosaurus Theropod (therizinosaur) Iren Dabasu Campanian Segnosaurus Theropod (therizinosaur) Jiufotang Aptian Chuanqilong Competitor (ankylosaur) Jiufotang Aptian Psittacosaurus Competitor (ceratopsian) Jiufotang Aptian Jinzhousaurus Competitor (iguanodontian) Jiufotang Aptian Huaxiapterus Competitor (other) Jiufotang Aptian Jidapterus Competitor (other) Jiufotang Aptian Nemicolopterus Competitor (other) Jiufotang Aptian Sinopterus Competitor (other) Jiufotang Aptian Aberratiodontus Theropod (avialan) Jiufotang Aptian Alethoalaornis Theropod (avialan) Jiufotang Aptian Archaeorhynchus Theropod (avialan) Jiufotang Aptian Boluochia Theropod (avialan) Jiufotang Aptian Cathayornis Theropod (avialan) Jiufotang Aptian Chaoyangia Theropod (avialan) Jiufotang Aptian Confuciusornis Theropod (avialan) Jiufotang Aptian Cuspirostrisornis Theropod (avialan)

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Jiufotang Aptian Dapingfangornis Theropod (avialan) Jiufotang Aptian Enantiornithes incertae Theropod (avialan) sedis (4 specimens) Jiufotang Aptian Eocathayornis Theropod (avialan) Jiufotang Aptian Fortunguavis Theropod (avialan) Jiufotang Aptian Houornis Theropod (avialan) Jiufotang Aptian Huoshanornis Theropod (avialan) Jiufotang Aptian Iteravis Theropod (avialan) Jiufotang Aptian Jeholornis Theropod (avialan) Jiufotang Aptian Jiangxiornis Theropod (avialan) Jiufotang Aptian Juehuaornis Theropod (avialan) Jiufotang Aptian Largirostrornis Theropod (avialan) Jiufotang Aptian Longchengornis Theropod (avialan) Jiufotang Aptian Longipteryx Theropod (avialan) Jiufotang Aptian Omnivoropteryx Theropod (avialan) Jiufotang Aptian Parabohaiornis Theropod (avialan) Jiufotang Aptian Parahongshanornis Theropod (avialan) Jiufotang Aptian Parapengornis Theropod (avialan) Jiufotang Aptian Pengornis Theropod (avialan) Jiufotang Aptian Rapaxavis Theropod (avialan) Jiufotang Aptian Sapeornis Theropod (avialan) Jiufotang Aptian Schizooura Theropod (avialan) Jiufotang Aptian Shengjingornis Theropod (avialan) Jiufotang Aptian Sinornis Theropod (avialan) Jiufotang Aptian Songlingornis Theropod (avialan) Jiufotang Aptian Sulcavis Theropod (avialan) Jiufotang Aptian Xiangornis Theropod (avialan) Jiufotang Aptian Yuanjiawaornis Theropod (avialan) Jiufotang Aptian Zhongjianornis Theropod (avialan) Jiufotang Aptian Zhouornis Theropod (avialan) Jiufotang Aptian Simillicaudipteryx Theropod (oviraptorosaur) Mangchua Cenomanian Zhongyuansaurus Competitor (ankylosaur) Mangchua Cenomanian Huanghetitan Competitor (sauropod) Mangchua Cenomanian Ruyangosaurus Competitor (sauropod) Mangchua Cenomanian Sauropoda incertae sedis Competitor (sauropod) (4 specimens) Mangchua Cenomanian Xianshanosaurus Competitor (sauropod) Mangchua Cenomanian Ornithomimosauria Theropod incertae sedis (1 (ornithomimosaur) specimen) Mangchua Cenomanian Luoyanggia Theropod (oviraptorosaur) Nanxiong Maastrichtian Titanosauria incertae sedis Competitor (sauropod)

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(1 specimen) Nanxiong Maastrichtian Tianyusaurus Competitor (squamate) Nanxiong Maastrichtian Banji Theropod (oviraptorosaur) Nanxiong Maastrichtian Ganzhousaurus Theropod (oviraptorosaur) Nanxiong Maastrichtian Huanansaurus Theropod (oviraptorosaur) Nanxiong Maastrichtian Jiangxisaurus Theropod (oviraptorosaur) Nanxiong Maastrichtian Nankangia Theropod (oviraptorosaur) Nanxiong Maastrichtian Oviraptorosauria incertae Theropod sedis (1 specimen) (oviraptorosaur) Nanxiong Maastrichtian Nanshiungosaurus Theropod (therizinosaur) Nemegt Maastrichtian Ankylosauria incertae Competitor sedis (9 specimens) (ankylosaur) Nemegt Maastrichtian Tarchia Competitor (ankylosaur) Nemegt Maastrichtian Bagaceratops Competitor (ceratopsian) Nemegt Maastrichtian Protoceratopsidae incertae Competitor sedis (3 specimens) (ceratopsian) Nemegt Maastrichtian Barsboldia Competitor (iguanodontian) Nemegt Maastrichtian Hadrosauridae incertae Competitor sedis (6 specimens) (iguanodontian) Nemegt Maastrichtian Saurolophus Competitor (iguanodontian) Nemegt Maastrichtian Ornithischia incertae sedis Competitor (other) (1 specimen) Nemegt Maastrichtian Pachycephalosauria Competitor incertae sedis (6 (pachycephalosaur) specimens) Nemegt Maastrichtian Prenocephale Competitor (pachycephalosaur) Nemegt Maastrichtian Nemegtosaurus Competitor (sauropod) Nemegt Maastrichtian Opisthocoelicaudia Competitor (sauropod) Nemegt Maastrichtian Sauropoda incertae sedis Competitor (sauropod) (7 specimens) Nemegt Maastrichtian Alvarezsauridae incertae Theropod (alvarezsaur) sedis (1 specimen) Nemegt Maastrichtian Mononykus Theropod (alvarezsaur) Nemegt Maastrichtian Avialae incertae sedis (1 Theropod (avialan) specimen)

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Nemegt Maastrichtian Gurilynia Theropod (avialan) Nemegt Maastrichtian Teviornis Theropod (avialan) Nemegt Maastrichtian Anserimimus Theropod (ornithomimosaur) Nemegt Maastrichtian Deinocheirus Theropod (ornithomimosaur) Nemegt Maastrichtian Gallimimus Theropod (ornithomimosaur) Nemegt Maastrichtian Ornithomimosauria Theropod incertae sedis (6 (ornithomimosaur) specimens) Nemegt Maastrichtian Ajancingenia Theropod (oviraptorosaur) Nemegt Maastrichtian Avimimus Theropod (oviraptorosaur) Nemegt Maastrichtian Elmisaurus Theropod (oviraptorosaur) Nemegt Maastrichtian Nemegtomaia Theropod (oviraptorosaur) Nemegt Maastrichtian Nomingia Theropod (oviraptorosaur) Nemegt Maastrichtian Oviraptorosauria incertae Theropod sedis (8 specimens) (oviraptorosaur) Nemegt Maastrichtian Therizinosaurus Theropod (therizinosaur) Pingling Maastrichtian Nodosauridae incertae Competitor sedis (1 specimen) (ankylosaur) Pingling Maastrichtian Hadrosauridae incertae Competitor sedis (1 specimen) (iguanodontian) Pingling Maastrichtian Sauropoda incertae sedis Competitor (sauropod) (1 specimen) Pingling Maastrichtian Shixinggia Theropod (oviraptorosaur) Qiupa Cenomanian Ankylosauria incertae Competitor sedis (1 specimen) (ankylosaur) Qiupa Cenomanian Yubaatar Competitor (mammaliamorph) Qiupa Cenomanian Ornithopoda incertae sedis Competitor (other) (1 specimen) Qiupa Cenomanian Funiusaurus Competitor (squamate) Qiupa Cenomanian Tianyusaurus Competitor (squamate) Qiupa Cenomanian Avialae incertae sedis (1 Theropod (avialan) specimen) Qiupa Cenomanian Qiupalong Theropod (ornithomimosaur) Qiupa Cenomanian Yulong Theropod

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(oviraptorosaur) Shahai Aptian Ceratopsia incertae sedis Competitor (1 specimen) (ceratopsian) Shahai Aptian Iguanodontia incertae Competitor sedis (1 specimen) (iguanodontian) Shahai Aptian Heishanobaatar Competitor (mammaliamorph) Shahai Aptian Kielanobaatar Competitor (mammaliamorph) Shahai Aptian Multituberculata incertae Competitor sedis (1 specimen) (mammaliamorph) Shahai Aptian Sinobaatar Competitor (mammaliamorph) Shahai Aptian Asiatosaurus Competitor (sauropod) Shahai Aptian Incisivosaurus Theropod (oviraptorosaur) Wulansuhai Campanian Linhenykus Theropod (alvarezsaur) Wulansuhai Campanian Wulatelong Theropod (oviraptorosaur) Yixian Aptian Liaoningosaurus Competitor (ankylosaur) Yixian Aptian Liaoceratops Competitor (ceratopsian) Yixian Aptian Psittacosaurus Competitor (ceratopsian) Yixian Aptian Bolong Competitor (iguanodontian) Yixian Aptian Sinobaatar Competitor (mammaliamorph) Yixian Aptian Jeholosaurus Competitor (other) Yixian Aptian Dongbeititan Competitor (sauropod) Yixian Aptian Euhelopus Competitor (sauropod) Yixian Aptian Sauropoda incertae sedis Competitor (sauropod) (2 specimens) Yixian Aptian Archaeorhynchus Theropod (avialan) Yixian Aptian Avialae incertae sedis (3 Theropod (avialan) specimens) Yixian Aptian Confuciusornis Theropod (avialan) Yixian Aptian Dalingheornis Theropod (avialan) Yixian Aptian Eoenantiornis Theropod (avialan) Yixian Aptian Grabauornis Theropod (avialan) Yixian Aptian Hongshanornis Theropod (avialan) Yixian Aptian Jeholornis Theropod (avialan) Yixian Aptian Jianchangornis Theropod (avialan) Yixian Aptian Jibeinia Theropod (avialan)

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Yixian Aptian Jinzhouornis Theropod (avialan) Yixian Aptian Liaoningornis Theropod (avialan) Yixian Aptian Liaoxiornis Theropod (avialan) Yixian Aptian Longicrusavis Theropod (avialan) Yixian Aptian Longirostravis Theropod (avialan) Yixian Aptian Parapengornis Theropod (avialan) Yixian Aptian Sapeornis Theropod (avialan) Yixian Aptian Shanweiniao Theropod (avialan) Yixian Aptian Tianyuornis Theropod (avialan) Yixian Aptian Vescornis Theropod (avialan) Yixian Aptian Xinghaiornis Theropod (avialan) Yixian Aptian Zhongornis Theropod (avialan) Yixian Aptian Hexing Theropod (ornithomimosaur) Yixian Aptian Shenzhousaurus Theropod (ornithomimosaur) Yixian Aptian Caudipteryx Theropod (oviraptorosaur) Yixian Aptian Incisivosaurus Theropod (oviraptorosaur) Yixian Aptian Ningyuansaurus Theropod (oviraptorosaur) Yixian Aptian Protarchaeopteryx Theropod (oviraptorosaur) Yixian Aptian Beipiaosaurus Theropod (therizinosaur) Yixian Aptian Jianchangosaurus Theropod (therizinosaur)

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Appendix B: Additional Herbivore Occurrence Data Added to Expanded Dataset

Formation Geologic stage Genus Category Aguja Maastrichtian Ankylosauria incertae Competitor sedis (4 specimens) (ankylosaur) Aguja Maastrichtian Edmontonia Competitor (ankylosaur) Aguja Maastrichtian Agujaceratops Competitor (ceratopsian) Aguja Maastrichtian Ceratopsia incertae Competitor sedis (8 specimens) (ceratopsian) Aguja Maastrichtian Anguomastacator Competitor (iguanodontian) Aguja Maastrichtian Claosaurus Competitor (iguanodontian) Aguja Maastrichtian Hadrosauria incertae Competitor sedis (22 specimens) (iguanodontian) Aguja Maastrichtian Kritosaurus Competitor (iguanodontian) Aguja Maastrichtian Cimexomys Competitor (mammaliamorph) Aguja Maastrichtian Cimolodon Competitor (mammaliamorph) Aguja Maastrichtian Cimolomys Competitor (mammaliamorph) Aguja Maastrichtian Meniscoessus Competitor (mammaliamorph) Aguja Maastrichtian Mesodma Competitor (mammaliamorph) Aguja Maastrichtian Multituberculata Competitor incertae sedis (5 (mammaliamorph) specimens) Aguja Maastrichtian Paracimexomys Competitor (mammaliamorph) Aguja Maastrichtian Ornithischia incertae Competitor (other) sedis (3 specimens) Aguja Maastrichtian Pachycephalosauria Competitor incertae sedis (5 (pachycephalosaur) specimens) Aguja Maastrichtian Texacephale Competitor (pachycephalosaur) Aguja Maastrichtian Alamosaurus Competitor (sauropod) Aguja Maastrichtian Sauropoda incertae Competitor sedis (1 specimen) (sauropod) Aguja Maastrichtian Avialae incertae sedis Theropod (avialan)

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(4 specimens) Aguja Maastrichtian Ornithomimidae Theropod incertae sedis (6 (ornithomimosaur) specimens) Aguja Maastrichtian Ornithomimus Theropod (ornithomimosaur) Aguja Maastrichtian Struthiomimus Theropod (ornithomimosaur) Aguja Maastrichtian Chirostenotes Theropod (oviraptorosaur) Aguja Maastrichtian Leptorhynchos Theropod (oviraptorosaur) Allen Maastrichtian Ankylosauria incertae Competitor sedis (1 specimen) (ankylosaur) Allen Maastrichtian Iguanodontian Competitor incertae sedis (6 (iguanodontian) specimen) Allen Maastrichtian Willinakaqe Competitor (iguanodontian) Allen Maastrichtian Trapalcotherium Competitor (mammaliamorph) Allen Maastrichtian Ornithopoda incertae Competitor (other) sedis (1 specimen) Allen Maastrichtian Aeolosaurus Competitor (sauropod) Allen Maastrichtian Bonatitan Competitor (sauropod) Allen Maastrichtian Lapampasaurus Competitor (sauropod) Allen Maastrichtian Laplatasaurus Competitor (sauropod) Allen Maastrichtian Neuquensaurus Competitor (sauropod) Allen Maastrichtian Panamericansaurus Competitor (sauropod) Allen Maastrichtian Rocasaurus Competitor (sauropod) Allen Maastrichtian Sauropoda incertae Competitor sedis (10 specimens) (sauropod) Allen Maastrichtian Bonapartenykus Theropod (alvarezsaur) Allen Maastrichtian Avialae incertae sedis Theropod (avialan) (1 specimen) Allen Maastrichtian Limenavis Theropod (avialan) Bajo de la Carpa Santonian Notosuchus Competitor (other) Bajo de la Carpa Santonian Bonitasaura Competitor

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(sauropod) Bajo de la Carpa Santonian Comahuesaurus Competitor (sauropod) Bajo de la Carpa Santonian Neuquensaurus Competitor (sauropod) Bajo de la Carpa Santonian Sauropoda incertae Competitor sedis (3 specimens) (sauropod) Bajo de la Carpa Santonian Traukutitan Competitor (sauropod) Bajo de la Carpa Santonian Achillesaurus Theropod (alvarezsaur) Bajo de la Carpa Santonian Alvarezsaurus Theropod (alvarezsaur) Bajo de la Carpa Santonian Avialae incertae sedis Theropod (avialan) (2 specimens) Bajo de la Carpa Santonian Neuquenornis Theropod (avialan) Bajo de la Carpa Santonian Patagopteryx Theropod (avialan) Bayan Gobi Aptian Psittacosaurus Competitor (ceratopsian) Bayan Gobi Aptian Penelopognathus Competitor (iguanodontian) Bayan Gobi Aptian Alxasaurus Theropod (therizinosaur) Baynshiree Campanian Ankylosauria incertae Competitor sedis (9 specimens) (ankylosaur) Baynshiree Campanian Pinacosaurus Competitor (ankylosaur) Baynshiree Campanian Talarurus Competitor (ankylosaur) Baynshiree Campanian Tsagantegia Competitor (ankylosaur) Baynshiree Campanian Protoceratopsidae Competitor incertae sedis (1 (ceratopsian) specimen) Baynshiree Campanian Amtosaurus Competitor (iguanodontian) Baynshiree Campanian Bactrosaurus Competitor (iguanodontian) Baynshiree Campanian Iguanodontia incertae Competitor sedis (23 specimens) (iguanodontian) Baynshiree Campanian Ornithopoda incertae Competitor (other) sedis (1 specimen) Baynshiree Campanian Amtocephale Competitor (pachycephalosaur) Baynshiree Campanian Erketu Competitor (sauropod)

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Baynshiree Campanian Sauropoda incertae Competitor sedis (12 specimens) (sauropod) Baynshiree Campanian Deinocheirus Theropod (ornithomimosaur) Baynshiree Campanian Garudimimus Theropod (ornithomimosaur) Baynshiree Campanian Ornithomimosauria Theropod incertae sedis (8 (ornithomimosaur) specimens) Baynshiree Campanian Oviraptorosauria Theropod incertae sedis (1 (oviraptorosaur) specimen) Baynshiree Campanian Enigmosaurus Theropod (therizinosaur) Baynshiree Campanian Erlikosaurus Theropod (therizinosaur) Baynshiree Campanian Therizinosauria Theropod incertae sedis (3 (therizinosaur) specimens) Candeleros Cenomanian Iguanodontia incertae Competitor sedis (1 specimen) (iguanodontian) Candeleros Cenomanian Kaikaifilusaurus Competitor (other) Candeleros Cenomanian Priosphenodon Competitor (other) Candeleros Cenomanian Andesaurus Competitor (sauropod) Candeleros Cenomanian Limaysaurus Competitor (sauropod) Candeleros Cenomanian Nopcsaspondylus Competitor (sauropod) Candeleros Cenomanian Rayososaurus Competitor (sauropod) Candeleros Cenomanian Sauropoda incertae Competitor sedis (2 specimens) (sauropod) Candeleros Cenomanian Iguanidae incertae Competitor sedis (1 specimen) (squamate) Candeleros Cenomanian Alnashetri Theropod (alvarezsaur) Cedar Mountain Albian Animantarx Competitor (ankylosaur) Cedar Mountain Albian Anyklosauria incertae Competitor sedis (13 specimens) (ankylosaur) Cedar Mountain Albian Cedarpelta Competitor (ankylosaur) Cedar Mountain Albian Gastonia Competitor (ankylosaur) Cedar Mountain Albian Hoplitosaurus Competitor

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(ankylosaur) Cedar Mountain Albian Peloroplites Competitor (ankylosaur) Cedar Mountain Albian Sauropelta Competitor (ankylosaur) Cedar Mountain Albian Cedrorestes Competitor (iguanodontian) Cedar Mountain Albian Eolambia Competitor (iguanodontian) Cedar Mountain Albian Hippodraco Competitor (iguanodontian) Cedar Mountain Albian Iguanacolossus Competitor (iguanodontian) Cedar Mountain Albian Iguanodontia incertae Competitor sedis (11 specimens) (iguanodontian) Cedar Mountain Albian Planicoxa Competitor (iguanodontian) Cedar Mountain Albian Tenontosaurus Competitor (iguanodontian) Cedar Mountain Albian Ameribaatar Competitor (mammaliamorph) Cedar Mountain Albian Bryceomys Competitor (mammaliamorph) Cedar Mountain Albian Cedaromys Competitor (mammaliamorph) Cedar Mountain Albian Janumys Competitor (mammaliamorph) Cedar Mountain Albian Mesodma Competitor (mammaliamorph) Cedar Mountain Albian Multituberculata Competitor incertae sedis (5 (mammaliamorph) specimens) Cedar Mountain Albian Paracimexomys Competitor (mammaliamorph) Cedar Mountain Albian Ornithischia incertae Competitor (other) sedis (2 specimens) Cedar Mountain Albian Ornithopoda incertae Competitor (other) sedis (7 specimens) Cedar Mountain Albian Toxolophosaurus Competitor (other) Cedar Mountain Albian Brontomerus Competitor (sauropod) Cedar Mountain Albian Cedarosaurus Competitor (sauropod) Cedar Mountain Albian Sauropoda incertae Competitor sedis (8 specimens) (sauropod) Cedar Mountain Albian Venenosaurus Competitor

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(sauropod) Cedar Mountain Albian Bicuspidon Competitor (squamate) Cedar Mountain Albian Ornithomimosauria Theropod incertae sedis (1 (ornithomimosaur) specimen) Cedar Mountain Albian Falcarius Theropod (therizinosaur) Cedar Mountain Albian Martharaptor Theropod (therizinosaur) Chijinbao Barremian Sauropoda incertae Competitor sedis (1 specimen) (sauropod) Chijinbao Barremian Nanshiungosaurus Theropod (therizinosaur) Cloverly Albian Ankylosauria incertae Competitor sedis (7 specimens) (ankylosaur) Cloverly Albian Sauropelta Competitor (ankylosaur) Cloverly Albian Tatankacephalus Competitor (ankylosaur) Cloverly Albian Aquilops Competitor (ceratopsian) Cloverly Albian Ceratopsian incertae Competitor sedis (2 specimens) (ceratopsian) Cloverly Albian Tenontosaurus Competitor (iguanodontian) Cloverly Albian Bryceomys Competitor (mammaliamorph) Cloverly Albian Janumys Competitor (mammaliamorph) Cloverly Albian Multituberculata Competitor incertae sedis (2 (mammaliamorph) specimens) Cloverly Albian Paracimexomys Competitor (mammaliamorph) Cloverly Albian Ornithischia incertae Competitor (other) sedis (13 specimens) Cloverly Albian Ornithopoda incertae Competitor (other) sedis (1 specimen) Cloverly Albian Zephyrosaurus Competitor (other) Cloverly Albian Rugocaudia Competitor (sauropod) Cloverly Albian Sauropoda incertae Competitor sedis (22 specimens) (sauropod) Cloverly Albian Sauroposeidon Competitor (sauropod)

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Cloverly Albian Ornithomimus Theropod (ornithomimosaur) Cloverly Albian Microvenator Theropod (oviraptorosaur) Denver Maastrichtian Ankylosauria incertae Competitor sedis (2 specimens) (ankylosaur) Denver Maastrichtian Edmontonia Competitor (ankylosaur) Denver Maastrichtian Ceratopsia incertae Competitor sedis (17 specimens) (ceratopsian) Denver Maastrichtian Triceratops Competitor (ceratopsian) Denver Maastrichtian Hadrosauria incertae Competitor sedis (3 specimens) (iguanodontian) Denver Maastrichtian Pachycephalosaurus Competitor (pachycephalosaur) Denver Maastrichtian Ornithomimus Theropod (ornithomimosaur) Dinosaur Park Campanian Ankylosauria incertae Competitor sedis (50 specimens) (ankylosaur) Dinosaur Park Campanian Anodontosaurus Competitor (ankylosaur) Dinosaur Park Campanian Dyoplosaurus Competitor (ankylosaur) Dinosaur Park Campanian Edmontonia Competitor (ankylosaur) Dinosaur Park Campanian Euoplocephalus Competitor (ankylosaur) Dinosaur Park Campanian Nodosaurus Competitor (ankylosaur) Dinosaur Park Campanian Panoplosaurus Competitor (ankylosaur) Dinosaur Park Campanian Scolosaurus Competitor (ankylosaur) Dinosaur Park Campanian Anchiceratops Competitor (ceratopsian) Dinosaur Park Campanian Centrosaurus Competitor (ceratopsian) Dinosaur Park Campanian Ceratopsia incertae Competitor sedis (49 specimens) (ceratopsian) Dinosaur Park Campanian Chasmosaurus Competitor (ceratopsian) Dinosaur Park Campanian Mercuriceratops Competitor (ceratopsian) Dinosaur Park Campanian Styracosaurus Competitor (ceratopsian)

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Dinosaur Park Campanian Unescoceratops Competitor (ceratopsian) Dinosaur Park Campanian Vagaceratops Competitor (ceratopsian) Dinosaur Park Campanian Brachylophosaurus Competitor (iguanodontian) Dinosaur Park Campanian Corythosaurus Competitor (iguanodontian) Dinosaur Park Campanian Gryposaurus Competitor (iguanodontian) Dinosaur Park Campanian Hadrosaur incertae Competitor sedis (120 specimens) (iguanodontian) Dinosaur Park Campanian Lambeosaurus Competitor (iguanodontian) Dinosaur Park Campanian Parasaurolophus Competitor (iguanodontian) Dinosaur Park Campanian Prosaurolophus Competitor (iguanodontian) Dinosaur Park Campanian Multituberculata Competitor incertae sedis (29 (mammaliamorph) specimens) Dinosaur Park Campanian Ornithischia incertae Competitor (other) sedis (2 specimens) Dinosaur Park Campanian Thescelosaurus Competitor (other) Dinosaur Park Campanian Pachycephalosauria Competitor incertae sedis (8 (pachycephalosaur) specimens) Dinosaur Park Campanian Sphaerotholus Competitor (pachycephalosaur) Dinosaur Park Campanian Stegoceras Competitor (pachycephalosaur) Dinosaur Park Campanian Avialae incertae sedis Theropod (avialan) (21 specimens) Dinosaur Park Campanian Palintropus Theropod (avialan) Dinosaur Park Campanian Ornithomimidae Theropod incertae sedis (8 (ornithomimosaur) specimens) Dinosaur Park Campanian Ornithomimus Theropod (ornithomimosaur) Dinosaur Park Campanian Struthiomimus Theropod (ornithomimosaur) Dinosaur Park Campanian Avimimus Theropod (oviraptorosaur) Dinosaur Park Campanian Caenagnathus Theropod (oviraptorosaur) Dinosaur Park Campanian Chirostenotes Theropod

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(oviraptorosaur) Dinosaur Park Campanian Leptorhynchos Theropod (oviraptorosaur) Ferris Maastrichtian Ankylosaurus Competitor (ankylosaur) Ferris Maastrichtian Edmontonia Competitor (ankylosaur) Ferris Maastrichtian Ceratopsia incertae Competitor sedis (25 specimens) (ceratopsian) Ferris Maastrichtian Triceratops Competitor (ceratopsian) Ferris Maastrichtian Hadrosauria incertae Competitor sedis (12 specimens) (iguanodontian) Ferris Maastrichtian Cimolodon Competitor (mammaliamorph) Ferris Maastrichtian Meniscoessus Competitor (mammaliamorph) Ferris Maastrichtian Multituberculata Competitor incertae sedis (2 (mammaliamorph) specimens) Ferris Maastrichtian Ornithischia incertae Competitor (other) sedis (6 specimens) Ferris Maastrichtian Pachycephalosaurus Competitor (pachycephalosaur) Ferris Maastrichtian Ornithomimidae Theropod incertae sedis (4 (ornithomimosaur) specimens) Ferris Maastrichtian Ornithomimus Theropod (ornithomimosaur) Ferris Maastrichtian Struthiomimus Theropod (ornithomimosaur) Fruitland Campanian Ankylosauria incertae Competitor sedis (9 specimens) (ankylosaur) Fruitland Campanian Ceratopsia incertae Competitor sedis (61 specimens) (ceratopsian) Fruitland Campanian Pentaceratops Competitor (ceratopsian) Fruitland Campanian Titanoceratops Competitor (ceratopsian) Fruitland Campanian Hadrosauria incertae Competitor sedis (78 specimens) (iguanodontian) Fruitland Campanian Kritosaurus Competitor (iguanodontian) Fruitland Campanian Parasaurolophus Competitor (iguanodontian) Fruitland Campanian Cimolodon Competitor

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(mammaliamorph) Fruitland Campanian Essonodon Competitor (mammaliamorph) Fruitland Campanian Meniscoessus Competitor (mammaliamorph) Fruitland Campanian Mesodma Competitor (mammaliamorph) Fruitland Campanian Multituberculata Competitor incertae sedis (6 (mammaliamorph) specimens) Fruitland Campanian Paracimexomys Competitor (mammaliamorph) Fruitland Campanian Ornithischia incertae Competitor (other) sedis (18 specimens) Fruitland Campanian Ornithopoda incertae Competitor (other) sedis (1 specimen) Fruitland Campanian Thescelosaurus Competitor (other) Fruitland Campanian Pachycephalosauria Competitor incertae sedis (1 (pachycephalosaur) specimen) Fruitland Campanian Stegoceras Competitor (pachycephalosaur) Fruitland Campanian Sauropoda incertae Competitor sedis (2 specimens) (sauropod) Fruitland Campanian Ornithomimidae Theropod incertae sedis (9 (ornithomimosaur) specimens) Fruitland Campanian Ornithomimus Theropod (ornithomimosaur) Hell Creek Maastrichtian Ankylosauria incertae Competitor sedis (6 specimens) (ankylosaur) Hell Creek Maastrichtian Ankylosaurus Competitor (ankylosaur) Hell Creek Maastrichtian Edmontonia Competitor (ankylosaur) Hell Creek Maastrichtian Ceratopsia incertae Competitor sedis (104 specimens) (ceratopsian) Hell Creek Maastrichtian Leptoceratops Competitor (ceratopsian) Hell Creek Maastrichtian Torosaurus Competitor (ceratopsian) Hell Creek Maastrichtian Triceratops Competitor (ceratopsian) Hell Creek Maastrichtian Anatosaurus Competitor (iguanodontian) Hell Creek Maastrichtian Hadrosauria incertae Competitor

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sedis (67 specimens) (iguanodontian) Hell Creek Maastrichtian Cimexomys Competitor (mammaliamorph) Hell Creek Maastrichtian Cimolodon Competitor (mammaliamorph) Hell Creek Maastrichtian Cimolomys Competitor (mammaliamorph) Hell Creek Maastrichtian Essonodon Competitor (mammaliamorph) Hell Creek Maastrichtian Meniscoessus Competitor (mammaliamorph) Hell Creek Maastrichtian Mesodma Competitor (mammaliamorph) Hell Creek Maastrichtian Multituberculata Competitor incertae sedis (10 (mammaliamorph) specimens) Hell Creek Maastrichtian Neoplagiaulax Competitor (mammaliamorph) Hell Creek Maastrichtian Paracimexomys Competitor (mammaliamorph) Hell Creek Maastrichtian Stygimys Competitor (mammaliamorph) Hell Creek Maastrichtian Valenopsalis Competitor (mammaliamorph) Hell Creek Maastrichtian Ornithischia incertae Competitor (other) sedis (6 specimens) Hell Creek Maastrichtian Ornithopoda incertae Competitor (other) sedis (6 specimens) Hell Creek Maastrichtian Thescelosaurus Competitor (other) Hell Creek Maastrichtian Pachycephalosauria Competitor incertae sedis (7 (pachycephalosaur) specimens) Hell Creek Maastrichtian Pachycephalosaurus Competitor (pachycephalosaur) Hell Creek Maastrichtian Sphaerotholus Competitor (pachycephalosaur) Hell Creek Maastrichtian Avialae incertae sedis Theropod (avialan) (20 specimens) Hell Creek Maastrichtian Avisaurus Theropod (avialan) Hell Creek Maastrichtian Ornithomimidae Theropod incertae sedis (10 (ornithomimosaur) specimens) Hell Creek Maastrichtian Ornithomimus Theropod (ornithomimosaur) Hell Creek Maastrichtian Anzu Theropod (oviraptorosaur)

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Hell Creek Maastrichtian Caenagnathus Theropod (oviraptorosaur) Hell Creek Maastrichtian Chirostenotes Theropod (oviraptorosaur) Hell Creek Maastrichtian Oviraptorosauria Theropod incertae sedis (9 (oviraptorosaur) specimens) Horseshoe Canyon Campanian Ankylosauria incertae Competitor sedis (4 specimens) (ankylosaur) Horseshoe Canyon Campanian Anodontosaurus Competitor (ankylosaur) Horseshoe Canyon Campanian Edmontonia Competitor (ankylosaur) Horseshoe Canyon Campanian Euoplocephalus Competitor (ankylosaur) Horseshoe Canyon Campanian Anchiceratops Competitor (ceratopsian) Horseshoe Canyon Campanian Arrhinoceratops Competitor (ceratopsian) Horseshoe Canyon Campanian Ceratopsia incertae Competitor sedis (4 specimens) (ceratopsian) Horseshoe Canyon Campanian Eotriceratops Competitor (ceratopsian) Horseshoe Canyon Campanian Montanoceratops Competitor (ceratopsian) Horseshoe Canyon Campanian Pachyrhinosaurus Competitor (ceratopsian) Horseshoe Canyon Campanian Edmontosaurus Competitor (iguanodontian) Horseshoe Canyon Campanian Hadrosauria incertae Competitor sedis (6 specimens) (iguanodontian) Horseshoe Canyon Campanian Hypacrosaurus Competitor (iguanodontian) Horseshoe Canyon Campanian Saurolophus Competitor (iguanodontian) Horseshoe Canyon Campanian Parksosaurus Competitor (other) Horseshoe Canyon Campanian Polyglyphanodontia Competitor incertae sedis (1 (squamate) specimen) Horseshoe Canyon Campanian Albertonykus Theropod (alvarezsaur) Horseshoe Canyon Campanian Avialae incertae sedis Theropod (avialan) (4 specimens) Horseshoe Canyon Campanian Ornithomimidae Theropod incertae sedis (2 (ornithomimosaur) specimens)

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Horseshoe Canyon Campanian Ornithomimus Theropod (ornithomimosaur) Horseshoe Canyon Campanian Struthiomimus Theropod (ornithomimosaur) Horseshoe Canyon Campanian Epichirostenotes Theropod (oviraptorosaur) Huajiying Hauterivian Archaeornithura Theropod (avialan) Huajiying Hauterivian Eopengornis Theropod (avialan) Huajiying Hauterivian Jibeinia Theropod (avialan) Huajiying Hauterivian Paraprotopteryx Theropod (avialan) Huajiying Hauterivian Protopteryx Theropod (avialan) Huajiying Hauterivian Jinfengopteryx Theropod (other) Javkhlant Santonian Ceratopsian incertae Competitor sedis (1 specimen) (ceratopsian) Javkhlant Santonian Yamaceratops Competitor (ceratopsian) Javkhlant Santonian Haya Competitor (other) Javkhlant Santonian Albinykus Theropod (alvarezsaur) Javkhlant Santonian Enantiornithes Theropod (avialan) incertae sedis (1 specimen) Javkhlant Santonian Ornithomimidae Theropod incertae sedis (1 (ornithomimosaur) specimen) Judith River Campanian Ankylosauria incertae Competitor sedis (4 specimens) (ankylosaur) Judith River Campanian Edmontonia Competitor (ankylosaur) Judith River Campanian Euoplocephalus Competitor (ankylosaur) Judith River Campanian Panoplosaurus Competitor (ankylosaur) Judith River Campanian Albertaceratops Competitor (ceratopsian) Judith River Campanian Avaceratops Competitor (ceratopsian) Judith River Campanian Centrosaurus Competitor (ceratopsian) Judith River Campanian Ceratops Competitor (ceratopsian) Judith River Campanian Ceratopsia incertae Competitor sedis (8 specimens) (ceratopsian) Judith River Campanian Chasmosaurus Competitor (ceratopsian)

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Judith River Campanian Judiceratops Competitor (ceratopsian) Judith River Campanian Medusaceratops Competitor (ceratopsian) Judith River Campanian Mercuriceratops Competitor (ceratopsian) Judith River Campanian Brachylophosaurus Competitor (iguanodontian) Judith River Campanian Corythosaurus Competitor (iguanodontian) Judith River Campanian Hadrosauria incertae Competitor sedis (29 specimens) (iguanodontian) Judith River Campanian Kritosaurus Competitor (iguanodontian) Judith River Campanian Parasaurolophus Competitor (iguanodontian) Judith River Campanian Cimexomys Competitor (mammaliamorph) Judith River Campanian Cimolodon Competitor (mammaliamorph) Judith River Campanian Cimolomys Competitor (mammaliamorph) Judith River Campanian Meniscoessus Competitor (mammaliamorph) Judith River Campanian Mesodma Competitor (mammaliamorph) Judith River Campanian Multituberculata Competitor incertae sedis (4 (mammaliamorph) specimens) Judith River Campanian Paracimexomys Competitor (mammaliamorph) Judith River Campanian Ornithischia incertae Competitor (other) sedis (1 specimen) Judith River Campanian Ornithopoda incertae Competitor (other) sedis (3 specimens) Judith River Campanian Orodromeus Competitor (other) Judith River Campanian Stegoceras Competitor (pachycephalosaur) Judith River Campanian Avialae incertae sedis Theropod (avialan) (2 specimens) Judith River Campanian Ornithomimidae Theropod incertae sedis (2 (ornithomimosaur) specimens) Judith River Campanian Ornithomimus Theropod (ornithomimosaur) Judith River Campanian Chirostenotes Theropod

59

(oviraptorosaur) Kaiparowits Campanian Ceratopsia incertae Competitor sedis (10 specimens) (ceratopsian) Kaiparowits Campanian Kosmoceratops Competitor (ceratopsian) Kaiparowits Campanian Nasutoceratops Competitor (ceratopsian) Kaiparowits Campanian Utahceratops Competitor (ceratopsian) Kaiparowits Campanian Gryposaurus Competitor (iguanodontian) Kaiparowits Campanian Parasaurolophus Competitor (iguanodontian) Kaiparowits Campanian Cimolodon Competitor (mammaliamorph) Kaiparowits Campanian Cimolomys Competitor (mammaliamorph) Kaiparowits Campanian Meniscoessus Competitor (mammaliamorph) Kaiparowits Campanian Mesodma Competitor (mammaliamorph) Kaiparowits Campanian Multituberculata Competitor incertae sedis (1 (mammaliamorph) specimen) Kaiparowits Campanian Paracimexomys Competitor (mammaliamorph) Kaiparowits Campanian Ornithopoda incertae Competitor (other) sedis (1 specimen) Kaiparowits Campanian Enantiornithes Theropod (avialan) incertae sedis (1 specimen) Kaiparowits Campanian Ornithomimus Theropod (ornithomimosaur) Kaiparowits Campanian Hagryphus Theropod (oviraptorosaur) Khuren Dukh Albian Ankylosauria incertae Competitor sedis (1 specimen) (ankylosaur) Khuren Dukh Albian Altirhinus Competitor (iguanodontian) Khuren Dukh Albian Iguanodontia incertae Competitor sedis (2 specimens) (iguanodontian) Khuren Dukh Albian Harpymimus Theropod (ornithomimosaur) Kirkwood Berriasian Iguanodontia incertae Competitor sedis (1 specimen) (iguanodontian) Kirkwood Berriasian Ornithischia incertae Competitor (other)

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sedis (1 specimen) Kirkwood Berriasian Paranthodon Competitor (other) Kirkwood Berriasian Algoasaurus Competitor (sauropod) Kirkwood Berriasian Diplodocoidea Competitor incertae sedis (4 (sauropod) specimens) Kirkwood Berriasian Macronaria incertae Competitor sedis (5 specimens) (sauropod) Kirkwood Berriasian Sauropoda incertae Competitor sedis (2 specimens) (sauropod) Kirkwood Berriasian Nqwebasaurus Theropod (ornithomimosaur) Kirtland Campanian Ahshislepelta Competitor (ankylosaur) Kirtland Campanian Ankylosauria incertae Competitor sedis (10 specimens) (ankylosaur) Kirtland Campanian Nodocephalosaurus Competitor (ankylosaur) Kirtland Campanian Ziapelta Competitor (ankylosaur) Kirtland Campanian Ceratops Competitor (ceratopsian) Kirtland Campanian Ceratopsia incertae Competitor sedis (61 specimens) (ceratopsian) Kirtland Campanian Chasmosaurus Competitor (ceratopsian) Kirtland Campanian Pentaceratops Competitor (ceratopsian) Kirtland Campanian Titanoceratops Competitor (ceratopsian) Kirtland Campanian Anasazisaurus Competitor (iguanodontian) Kirtland Campanian Hadrosauria incertae Competitor sedis (63 specimens) (iguanodontian) Kirtland Campanian Kritosaurus Competitor (iguanodontian) Kirtland Campanian Naashoibitosaurus Competitor (iguanodontian) Kirtland Campanian Parasaurolophus Competitor (iguanodontian) Kirtland Campanian Saurolophus Competitor (iguanodontian) Kirtland Campanian Cimolodon Competitor (mammaliamorph) Kirtland Campanian Essonodon Competitor

61

(mammaliamorph) Kirtland Campanian Kimbetohia Competitor (mammaliamorph) Kirtland Campanian Meniscoessus Competitor (mammaliamorph) Kirtland Campanian Mesodma Competitor (mammaliamorph) Kirtland Campanian Mutituberculata Competitor incertae sedis (5 (mammaliamorph) specimens) Kirtland Campanian Paracimexomys Competitor (mammaliamorph) Kirtland Campanian Ornithischia incertae Competitor (other) sedis (18 specimens) Kirtland Campanian Ornithopoda incertae Competitor (other) sedis (1 specimen) Kirtland Campanian Pachycephalosauria Competitor incertae sedis (1 (pachycephalosaur) specimen) Kirtland Campanian Prenocephale Competitor (pachycephalosaur) Kirtland Campanian Sphaerotholus Competitor (pachycephalosaur) Kirtland Campanian Stegoceras Competitor (pachycephalosaur) Kirtland Campanian Alamosaurus Competitor (sauropod) Kirtland Campanian Sauropoda incertae Competitor sedis (2 specimens) (sauropod) Kirtland Campanian Ornithomimidae Theropod incertae sedis (7 (ornithomimosaur) specimens) Kirtland Campanian Struthiomimus Theropod (ornithomimosaur) La Huérguina Hauterivian Mantellisaurus Competitor (iguanodontian) La Huérguina Hauterivian Europejara Competitor (other) La Huérguina Hauterivian Ornithopoda incertae Competitor (other) sedis (1 specimen) La Huérguina Hauterivian Sauropoda incertae Competitor sedis (1 specimen) (sauropod) La Huérguina Hauterivian Avialae incertae sedis Theropod (avialan) (1 specimen) La Huérguina Hauterivian Concornis Theropod (avialan) La Huérguina Hauterivian Eoalulavis Theropod (avialan) La Huérguina Hauterivian Iberomesornis Theropod (avialan)

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La Huérguina Hauterivian Pelecanimimus Theropod (ornithomimosaur) Lance Maastrichtian Ankylosauria incertae Competitor sedis (2 specimens) (ankylosaur) Lance Maastrichtian Ankyosaurus Competitor (ankylosaur) Lance Maastrichtian Edmontonia Competitor (ankylosaur) Lance Maastrichtian Ceratopsia incertae Competitor sedis (13 specimens) (ceratopsian) Lance Maastrichtian Leptoceratops Competitor (ceratopsian) Lance Maastrichtian Torosaurus Competitor (ceratopsian) Lance Maastrichtian Triceratops Competitor (ceratopsian) Lance Maastrichtian Anatosaurus Competitor (iguanodontian) Lance Maastrichtian Iguanodontia incertae Competitor sedis (18 specimens) (iguanodontian) Lance Maastrichtian Allacodon Competitor (mammaliamorph) Lance Maastrichtian Camptomus Competitor (mammaliamorph) Lance Maastrichtian Cimexomys Competitor (mammaliamorph) Lance Maastrichtian Cimolodon Competitor (mammaliamorph) Lance Maastrichtian Cimolomys Competitor (mammaliamorph) Lance Maastrichtian Clemensodon Competitor (mammaliamorph) Lance Maastrichtian Essonodon Competitor (mammaliamorph) Lance Maastrichtian Meniscoessus Competitor (mammaliamorph) Lance Maastrichtian Mesodma Competitor (mammaliamorph) Lance Maastrichtian Multituberculata Competitor incertae sedis (18 (mammaliamorph) specimens) Lance Maastrichtian Neoplagiaulax Competitor (mammaliamorph) Lance Maastrichtian Paracimexomys Competitor (mammaliamorph) Lance Maastrichtian Paressonodon Competitor

63

(mammaliamorph) Lance Maastrichtian Parikimys Competitor (mammaliamorph) Lance Maastrichtian Thescelosaurus Competitor (other) Lance Maastrichtian Pachycephalosaurus Competitor (pachycephalosaur) Lance Maastrichtian Pachycephalosaurus Competitor incertae sedis (1 (pachycephalosaur) specimen) Lance Maastrichtian Iguanidae incertae Competitor sedis (1 specimen) (squamate) Lance Maastrichtian Pariguana Competitor (squamate) Lance Maastrichtian Alvarezsauridae Theropod incertae sedis (1 (alvarezsaur) specimen) Lance Maastrichtian Avialae incertae sedis Theropod (avialan) (7 specimens) Lance Maastrichtian Ornithomimus Theropod (ornithomimosaur) Majiacun Santonian Mosaiceratops Competitor (ceratopsian) Majiacun Santonian Nanyangosaurus Competitor (iguanodontian) Majiacun Santonian Zhenghenglong Competitor (iguanodontian) Majiacun Santonian Ornithopoda incertae Competitor (other) sedis (1 specimen) Majiacun Santonian Baotianmansaurus Competitor (sauropod) Majiacun Santonian Xixianykus Theropod (alvarezsaur) Moreno Hill Turonian Zuniceratops Competitor (ceratopsian) Moreno Hill Turonian Hadrosauria incertae Competitor sedis (2 specimens) (iguanodontian) Moreno Hill Turonian Jeyawati Competitor (iguanodontian) Moreno Hill Turonian Nothronychus Theropod (therizinosaur) Ojo Alamo Maastrichtian Ankylosauria incertae Competitor sedis (3 specimens) (ankylosaur) Ojo Alamo Maastrichtian Glyptodontopelta Competitor (ankylosaur) Ojo Alamo Maastrichtian Panoplosaurus Competitor (ankylosaur)

64

Ojo Alamo Maastrichtian Ceratopsia incertae Competitor sedis (7 specimens) (ceratopsian) Ojo Alamo Maastrichtian Ojoceratops Competitor (ceratopsian) Ojo Alamo Maastrichtian Pentaceratops Competitor (ceratopsian) Ojo Alamo Maastrichtian Hadrosauria incertae Competitor sedis (10 specimens) (iguanodontian) Ojo Alamo Maastrichtian Essonodon Competitor (mammaliamorph) Ojo Alamo Maastrichtian Meniscoessus Competitor (mammaliamorph) Ojo Alamo Maastrichtian Mesodma Competitor (mammaliamorph) Ojo Alamo Maastrichtian Multituberculata Competitor incertae sedis (1 (mammaliamorph) specimen) Ojo Alamo Maastrichtian Alamosaurus Competitor (sauropod) Ojo Alamo Maastrichtian Sauropoda incertae Competitor sedis (1 specimen) (sauropod) Ojo Alamo Maastrichtian Ornithomimidae Theropod incertae sedis (1 (ornithomimosaur) specimen) Ojo Alamo Maastrichtian Ojoraptorsaurus Theropod (oviraptorosaur) Oldman Campanian Ankylosauria incertae Competitor sedis (29 specimens) (ankylosaur) Oldman Campanian Euoplocephalus Competitor (ankylosaur) Oldman Campanian Albertaceratops Competitor (ceratopsian) Oldman Campanian Anchiceratops Competitor (ceratopsian) Oldman Campanian Centrosaurus Competitor (ceratopsian) Oldman Campanian Ceratopsia incertae Competitor sedis (24 specimens) (ceratopsian) Oldman Campanian Chasmosaurus Competitor (ceratopsian) Oldman Campanian Coronosaurus Competitor (ceratopsian) Oldman Campanian Prenoceratops Competitor (ceratopsian) Oldman Campanian Spinops Competitor (ceratopsian)

65

Oldman Campanian Wendiceratops Competitor (ceratopsian) Oldman Campanian Brachylophosaurus Competitor (iguanodontian) Oldman Campanian Gryposaurus Competitor (iguanodontian) Oldman Campanian Hadrosauria incertae Competitor sedis (28 specimens) (iguanodontian) Oldman Campanian Hypacrosaurus Competitor (iguanodontian) Oldman Campanian Lambeosaurus Competitor (iguanodontian) Oldman Campanian Cimexomys Competitor (mammaliamorph) Oldman Campanian Cimolodon Competitor (mammaliamorph) Oldman Campanian Cimolomys Competitor (mammaliamorph) Oldman Campanian Meniscoessus Competitor (mammaliamorph) Oldman Campanian Mesodma Competitor (mammaliamorph) Oldman Campanian Multituberculata Competitor incertae sedis (27 (mammaliamorph) specimens) Oldman Campanian Albertadromeus Competitor (other) Oldman Campanian Ornithopoda incertae Competitor (other) sedis (2 specimens) Oldman Campanian Thescelosaurus Competitor (other) Oldman Campanian Gravitholus Competitor (pachycephalosaur) Oldman Campanian Pachycephalosauria Competitor incertae sedis (13 (pachycephalosaur) specimens) Oldman Campanian Avialae incertae sedis Theropod (avialan) (16 specimens) Oldman Campanian Struthiomimus Theropod (ornithomimosaur) Portezuelo Turonian Iguanodontia incertae Competitor sedis (2 specimens) (iguanodontian) Portezuelo Turonian Ornithischia incertae Competitor (other) sedis (1 specimen) Portezuelo Turonian Ornithopoda incertae Competitor (other) sedis (1 specimen) Portezuelo Turonian Futalognkosaurus Competitor (sauropod)

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Portezuelo Turonian Sauropoda incertae Competitor sedis (4 specimens) (sauropod) Portezuelo Turonian Alvarezsauridae Theropod incertae sedis (1 (alvarezsaur) specimen) Portezuelo Turonian Patagonykus Theropod (alvarezsaur) Portezuelo Turonian Avialae incertae sedis Theropod (avialan) (1 specimen) Sao Khua Barremian Iguanodontia incertae Competitor sedis (2 specimens) (iguanodontian) Sao Khua Barremian Phuwiangosaurus Competitor (sauropod) Sao Khua Barremian Sauropoda incertae Competitor sedis (18 specimens) (sauropod) Sao Khua Barremian Avialae incertae sedis Theropod (avialan) (1 specimen) Sao Khua Barremian Kinnareemimus Theropod (ornithomimosaur) Sao Khua Barremian Ornithomimidae Theropod incertae sedis (1 (ornithomimosaur) specimen) Shishugou Oxfordian Hualianceratops Competitor (ceratopsian) Shishugou Oxfordian Yinlong Competitor (ceratopsian) Shishugou Oxfordian Bienotheroides Competitor (mammaliamorph) Shishugou Oxfordian Tritylodontidae Competitor incertae sedis (1 (mammaliamorph) specimen) Shishugou Oxfordian Yuanotherium Competitor (mammaliamorph) Shishugou Oxfordian Gongbusaurus Competitor (other) Shishugou Oxfordian Jiangjunosaurus Competitor (other) Shishugou Oxfordian Ornithischia incertae Competitor (other) sedis (1 specimen) Shishugou Oxfordian Ornithopoda incertae Competitor (other) sedis (1 specimen) Shishugou Oxfordian Bellusaurus Competitor (sauropod) Shishugou Oxfordian Klamelisaurus Competitor (sauropod) Shishugou Oxfordian Mamenchisauridae Competitor incertae sedis (1 (sauropod) specimen)

67

Shishugou Oxfordian Mamenchisaurus Competitor (sauropod) Shishugou Oxfordian Sauropoda incertae Competitor sedis (6 specimens) (sauropod) Shishugou Oxfordian Tienshanosaurus Competitor (sauropod) Shishugou Oxfordian Haplocheirus Theropod (alvarezsaur) Shishugou Oxfordian Limusaurus Theropod (other) Tiaojishan Oxfordian Arboroharamiya Competitor (mammaliamorph) Tiaojishan Oxfordian Megaconus Competitor (mammaliamorph) Tiaojishan Oxfordian Rugosodon Competitor (mammaliamorph) Tiaojishan Oxfordian Shenshou Competitor (mammaliamorph) Tiaojishan Oxfordian Xianshou Competitor (mammaliamorph) Tiaojishan Oxfordian Tianyulong Competitor (other) Tiaojishan Oxfordian Epidexipteryx Theropod (other) Tiaojishan Oxfordian Pedopenna Theropod (other) Tiaojishan Oxfordian Scansoriopteryx Theropod (other) Tiaojishan Oxfordian Yi Theropod (other) Toqui Tithonian Diplodocidae incertae Competitor sedis (2 specimens) (sauropod) Toqui Tithonian Sauropoda incertae Competitor sedis (2 specimens) (sauropod) Toqui Tithonian Chilesaurus Theropod (other) Two Medicine Campanian Ankylosauria incertae Competitor sedis (13 specimens) (ankylosaur) Two Medicine Campanian Dyoplosaurus Competitor (ankylosaur) Two Medicine Campanian Edmontonia Competitor (ankylosaur) Two Medicine Campanian Euoplocephalus Competitor (ankylosaur) Two Medicine Campanian Scolosaurus Competitor (ankylosaur) Two Medicine Campanian Achelousaurus Competitor (ceratopsian) Two Medicine Campanian Cerasinops Competitor (ceratopsian) Two Medicine Campanian Ceratopsia incertae Competitor sedis (35 specimens) (ceratopsian)

68

Two Medicine Campanian Einiosaurus Competitor (ceratopsian) Two Medicine Campanian Prenoceratops Competitor (ceratopsian) Two Medicine Campanian Rubeosaurus Competitor (ceratopsian) Two Medicine Campanian Acristavus Competitor (iguanodontian) Two Medicine Campanian Corythosaurus Competitor (iguanodontian) Two Medicine Campanian Glishades Competitor (iguanodontian) Two Medicine Campanian Gryposaurus Competitor (iguanodontian) Two Medicine Campanian Hadrosauria incertae Competitor sedis (19 specimens) (iguanodontian) Two Medicine Campanian Hypacrosaurus Competitor (iguanodontian) Two Medicine Campanian Maiasaura Competitor (iguanodontian) Two Medicine Campanian Prosaurolophus Competitor (iguanodontian) Two Medicine Campanian Multituberculata Competitor incertae sedis (1 (mammaliamorph) specimen) Two Medicine Campanian Paracimexomys Competitor (mammaliamorph) Two Medicine Campanian Ornithischia incertae Competitor (other) sedis (1 specimen) Two Medicine Campanian Ornithopoda incertae Competitor (other) sedis (4 specimens) Two Medicine Campanian Orodromeus Competitor (other) Two Medicine Campanian Pachycephalosauria Competitor incertae sedis (2 (pachycephalosaur) specimens) Two Medicine Campanian Avisaurus Theropod (avialan) Two Medicine Campanian Ornithomimidae Theropod incertae sedis (2 (ornithomimosaur) specimens) Two Medicine Campanian Leptorhynchos Theropod (oviraptorosaur) Ulansuhai Turonian Gobisaurus Competitor (ankylosaur) Ulansuhai Turonian Sauropoda incertae Competitor sedis (1 specimen) (sauropod) Ulansuhai Turonian Sinornithomimus Theropod

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(ornithomimosaur)

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Appendix C: Plant Occurrence Data

Formation Plants Cedar Mountain Bennettitales Cedar Mountain Cheriolepidiaceae Cedar Mountain Coniferales Cedar Mountain Magnoliopsida Cedar Mountain Podocarpaceae Cedar Mountain Schizaeceae Cedar Mountain Tempskyaceae Denver Dilleniidae Denver Magnoliidae Denver Paleonelumbo Denver Palmae Denver Platanaceae Denver Pteridopsida Denver Selaginellaceae Dinosaur Park Arecidae Dinosaur Park Coniferales Dinosaur Park Ginkgoaceae Dinosaur Park Platanaceae Fuxin Bennettitales Fuxin Ginkgoaceae Hell Creek Araucariaceae Hell Creek Arecidaes Hell Creek Azollaceae Hell Creek Berberidaceae Hell Creek Carpites Hell Creek Celastraceae Hell Creek Cercidiphyllaceae Hell Creek Coniferales Hell Creek Cycadales Hell Creek Dilleniidae Hell Creek Equistaceae Hell Creek Fagaceae Hell Creek Filicales Hell Creek Flacourtiaceae Hell Creek Hamamelidae Hell Creek Hanamelididae Hell Creek Hydropteridiaceae Hell Creek Leepierceia Hell Creek Magnoliidae Hell Creek Magnoliopsida Hell Creek Menispermaceae Hell Creek Nelumbonaceae

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Hell Creek Nymphaeaceae Hell Creek Platanaceae Hell Creek Polypodiaceae Hell Creek Proteales Hell Creek Ranunculaceae Hell Creek Rosidae Hell Creek Salviniaceae Hell Creek Sapindaceae Hell Creek Sterculiaceae Hell Creek Taxodiaceae Hell Creek Tiliaceae Hell Creek Trochodendrales Hell Creek Urticaceae Hell Creek Zingiberidae Horseshoe Canyon Arecidae Horseshoe Canyon Azollaceae Horseshoe Canyon Blechnaceae Horseshoe Canyon Coniferales Horseshoe Canyon Cupressaceae Horseshoe Canyon Dennstaedtiaceae Horseshoe Canyon Equisetaceae Horseshoe Canyon Marsileaceae Horseshoe Canyon Trapaceae Iren Dabasu Campanulaceae Iren Dabasu Caprifoliaceae Iren Dabasu Commelinidae Iren Dabasu Ericaceae Iren Dabasu Hamamelidae Iren Dabasu Hamamelidiaceae Iren Dabasu Leptolepidites Iren Dabasu Liliidae Iren Dabasu Lycopodiaceae Iren Dabasu Menispermaceae Iren Dabasu Pinales Iren Dabasu Podocarpaceae Iren Dabasu Proteales Iren Dabasu Pteridopsida Iren Dabasu Santalales Iren Dabasu Selaginellaceae Iren Dabasu Sphagnaceae Judith River Asteraceae Judith River Azollaceae Judith River Dilleniidae Judith River Liliidae Judith River Magnoliidae

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Judith River Platanaceae Judith River Pteridopsida Judith River Schizaeceae Judith River Selaginellaceae Kirkwood Araucariaceae Kirkwood Bennettitales Kirkwood Pentoxylaceae Kirkwood Podocarpaceae Kirkwood Polypodiopsida Kirkwood Pteridopsida Kirkwood Sphenopteridae Kirtland Aspleniaceae Kirtland Bechnaeceae Kirtland Dilleniidae Kirtland Fagaceae Kirtland Hamamelidae Kirtland Leguminosae Kirtland Magnoliidae Kirtland Magnoliopsida Kirtland Menispermaceae Kirtland Rosidae Kirtland Saliacaceae Kirtland Salviniaceae Kirtland Taxodiaceae La Huérguina Araucariaceae La Huérguina Bennettitales La Huérguina Cheirolepidiaceae La Huérguina Coniferales La Huérguina Matoniaceae La Huérguina Polypodiopsida La Huérguina Taxodiaceae Oldman Azollaceae Oldman Dilleniidae Oldman Lycopodiaceae Oldman Selaginellaceae Shahai Bennettitales Shahai Cheirolepidiaceae Shahai Coniferales Shahai Czekanowskiales Shahai Czekanowskiales Shahai Ginkgoaceae Shahai Podocarpaceae Shahai Schizaeceae Shahai Sphenopteridae Tiaojishan Bennettitales

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Tiaojishan Calamitaceae Tiaojishan Czekanowskiales Tiaojishan Dicksoniaceae Tiaojishan Peltaspermaceae Yixian Alismatidae Yixian Archaefructaceae Yixian Bennettitales Yixian Czekanowskiales Yixian Dicksoniaceae Yixian Equisetaceae Yixian Ginkgoaceae Yixian Podocarpaceae

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Appendix D: Average Global Sea Level of Examined Geologic Stages

Geologic stage Average sea level (m relative to present day) Maastrichtian 28.61 Santonian 20.73 Coniacian 20.17 Turonian 24.56 Cenomanian 46.29 Albian 3.6 Aptian -7.21 Barremian 3.18 Hauterivian -20.6 Berriasian -19.07 Tithonian -7.62

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University of Maryland Honor Pledge I pledge on my honor that I have not given or received any unauthorized assistance or plagiarized on this assignment.

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