Data from: Divergent feeding biomechanics in Late Cretaceous marine reptiles from the Western Interior Seaway
Data files
Mar 31, 2026 version files 141.08 KB
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1_perform_data.csv
5.92 KB
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1_R_code.r
32.58 KB
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2_dataset_WIS_MMR.csv
9.03 KB
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2_R_code.r
10.17 KB
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3_R_code.r
2.46 KB
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3_simulated_bite_force.csv
1.25 KB
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README.md
9.69 KB
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WIS_data.xlsx
68.29 KB
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WIS_ranges.txt
523 B
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WIS_tree.tre
1.16 KB
Abstract
Sympatry of numerous predatory marine reptiles appears to be the rule rather than the exception in many Mesozoic formations, implying that these lineages likely evolved some form of ecological partitioning. Many studies have focused on dental morphology as a proxy for the feeding habits of aquatic tetrapods, but much more ecological insight may be gained through simulations of the mechanical performance of craniomandibular elements. Here, we conducted the first, large-scale, comparative study of marine reptile jaw biomechanics, applying muscle-driven finite element analyses (FEA) on a dataset of high-resolution three-dimensional models. Our study-system included mosasaurids and polycotylid plesiosaurians from the Santonian-Maastrichtian of the Western Interior Seaway (WIS), a vast inland sea that stretched longitudinally across North America during the Late Cretaceous. Muscle insertions were identified to reconstruct jaw adductor muscles and simulate respective muscle and bite forces. We simulated realistic muscle traction dynamics during biting, including simulations at multiple opening angles and bite locations. We recover clearly distinct biomechanical performances among the sample, notably between the slender-snouted mosasaurids (e.g. Clidastes) plus polycotylids, and the robust-jawed mosasaurids (e.g. Prognathodon). By integrating jaw size, mechanical efficiency, and internal energy, we provide strong support for differential biting mechanics among these marine predators, which doubtless influenced their ecological role. Our results offer deeper insight into feeding ecologies in Late Cretaceous marine reptiles and provide a unified protocol to assess the role of feeding biomechanics in niche partitioning among sympatric marine reptiles from well-sampled regions.
Dataset DOI: 10.5061/dryad.j6q573nts
Description of the data and file structure
Linear measurements from mosasaurids and polycotylid plesiosaurians of the Western Interior Seaway, muscle force calculation, bite performance data are shown in "WIS_data.xlsx". To reproduce the analyses in the paper, use the R_scripts numbered from 1-3 with their corresponding .csv dataset numbered from 1-3. Be sure to import the phylogenetic topology and the stratigraphic ranges in the working directory.
Files and variables
File: 1_perform_data.csv
Description: Dataset to run with 1_R_code.r
* Taxon: Taxon name
* Clade: Clade name
* Subfamily: Subfamily name
* 7_ME1: mechanical efficiency for 7° gape and anterior biting point
* 7_ME2: mechanical efficiency for 7° gape and posterior biting point
* 7_AIE1: adjusted internal energy for 7° gape and anterior biting point
* 7_AIE2: adjusted internal energy for 7° gape and posterior biting point
* 7_IE1: adjusted internal energy (inverted) for 7° gape and anterior biting point
* 7_IE2: adjusted internal energy (inverted) for 7° gape and posterior biting point
* 15_ME1: mechanical efficiency for 15° gape and anterior biting point
* 15_ME2: mechanical efficiency for 15° gape and posterior biting point
* 15_AIE1: mechanical efficiency for 15° gape and anterior biting point
* 15_AIE2: mechanical efficiency for 15° gape and posterior biting point
* 15_IE1: adjusted internal energy (inverted) for 15° gape and anterior biting point
* 15_IE2: adjusted internal energy (inverted) for 15° gape and posterior biting point
* avg_ME1: average mechanical efficiency for anterior biting point
* avg_ME2: average mechanical efficiency for posterior posterior biting point
* avg_IE1: adjusted internal energy (inverted) for anterior biting point
* avg_IE2: adjusted internal energy (inverted) for posterior biting point
* avg_P1_1: average von Mises stress in point 1 for anterior biting point
* avg_P1_2: average von Mises stress in point 2 for anterior biting point
* avg_P1_3: average von Mises stress in point 3 for anterior biting point
* avg_P1_4: average von Mises stress in point 4 for anterior biting point
* avg_P1_5: average von Mises stress in point 5 for anterior biting point
* avg_P2_1: average von Mises stress in point 1 for posterior biting point
* avg_P2_2: average von Mises stress in point 2 for posterior biting point
* avg_P2_3: average von Mises stress in point 3 for posterior biting point
* avg_P2_4: average von Mises stress in point 4 for posterior biting point
* avg_P2_5: average von Mises stress in point 5 for posterior biting point
* DLAR: depressor arm lever ratio
* ALAR: adductor lever arm ratio
* MA: mechanical advantage at mid-dentigerous length
* massare_guild: variable for dental morphoguild (Massare 1987)
* fischer_guild: variable for dental morphoguild (Fischer et al. 2022)
File: 2_dataset_WIS_MMR.csv
Description: Dataset to run with 2_R_code.r
* Taxon: Taxon name
* Clade: Clade name
* Subfamily: Subfamily name
* 1-20_(ratio name): functional ratios used to produce the functional morphospaces
* Jaw_L: jaw length in millimeters
* 7_ME1: mechanical efficiency for 7° gape and anterior biting point
* 7_ME2: mechanical efficiency for 7° gape and posterior biting point
* 7_AIE1: adjusted internal energy for 7° gape and anterior biting point
* 7_AIE2: adjusted internal energy for 7° gape and posterior biting point
* 7_IE1: adjusted internal energy (inverted) for 7° gape and anterior biting point
* 7_IE2: adjusted internal energy (inverted) for 7° gape and posterior biting point
* 15_ME1: mechanical efficiency for 15° gape and anterior biting point
* 15_ME2: mechanical efficiency for 15° gape and posterior biting point
* 15_AIE1: mechanical efficiency for 15° gape and anterior biting point
* 15_AIE2: mechanical efficiency for 15° gape and posterior biting point
* 15_IE1: adjusted internal energy (inverted) for 15° gape and anterior biting point
* 15_IE2: adjusted internal energy (inverted) for 15° gape and posterior biting point
File: 3_simulated_bite_force.csv
Description: Dataset to run with 3_R_code.r
* Taxon: Taxon name
* Clade: Clade name
* Subfamily: Subfamily name
* mandibleL_[mm]: jaw length
* anterior_biteforce[N]: bite force in case of anterior biting point in Newton
* posterior_biteforce[N]: bite force in case of posterior biting point in Newton
File: WIS_data.xlsx
Description: General dataset with muscle reconstruction data, measurements used to obtain functional ratios and FEA outputs. No script runs on this worksheet.
Data: Sheet that contains muscle reconstruction information.
* Taxon: Taxon name
* Muscle: muscle name
* Origin_X, Y, Z = center of mass of muscle origin coordinates
* X, Y, Z = center of mass of muscle insertion coordinates
* Muscle origin area: surface of muscle origin attachment
* Muscle insertion area: surface of muscle insertion attachment
* Muscle length (mm): calculated muscle length
* Muscle Volume (mm^3): calculated muscle volume
* Fiber length (mm): calculated muscle fiber length
* Pennation: muscle pennation angle
* PCSA: calculated physiological cross-section
* T-specific: constant relative to muscle force
* Muscle force (N): calculated muscle force
* Total muscle force: sum of muscle forces
* Tot muscle area: sum of muscle attachment areas
Measurements: Sheet that contains measurements information in millimeters.
* Taxon: Taxon name
* Source: source of measurement with details of specimen number and relative paper
* Clade: clade name
* Mandible_L: mandible length
* Dentigerous_L: length of the tooth-bearing portion of the mandible
* MidDentig_Mand_D: dorsoventral depth of mandible at mid-dentigerous region
* MidDentig_to_Q: relative position of mid-dentigerous region to quadrate
* Coronoid_D: dorsoventral height of the coronoid process
* Coronoid_to_Q: relative position of coronoid process to quadrate
* Retroart: length of the retroarticular process
* Snout_L: length of the snout anterior to the orbit
* MidDentig_Snout_D: dorsoventral depth of snout at mid-dentigerous level
* MidDentig_Snout_W: mediolateral width of snout at mid-dentigerous level
* Skull_D_anterior_to_orbit: dorsoventral depth of skull anterior to orbit
* Skull_W_anterior_to_orbit: mediolateral width of skull anterior to orbit
* Orbit_H: vertical height of the orbit
* Orbit_L: anteroposterior length of the orbit
* Occular_offset: relative position of orbit compared to the dentigerous line
* STF_max_L: maximum length of the supratemporal fenestra
* STF_ortho_W: orthogonal width of the supratemporal fenestra
* Parietal_for_L: length of the parietal foramen
* Crown_H: apicobasal height of the tooth crown
* Crown_basal_mesiodistal_W: mesiodistal width at crown base
* Crown_basal_labiolingual_W: labiolingual width at crown base
* Crown_offset: positional offset of crown tip relative to crown base center
* dentary_alveolus_L: length of alveoli at mid-dentigerous length
* interalveoli_distance_L: spacing between of alveoli at mid-dentigerous length
* CARINAE: presence of carinae on teeth (discrete)
* HETERODONTY: presence or absence of heterodonty (discrete)
FEA: Sheet that contains FEA outputs and performance variables.
* Taxon: Taxon name
* Gape (°): gape opening of the analysis
* Teeth position = anterior (1) or posterior (2) bite point
* Force on the jaw (N): reaction force from FEA
* work of external forces: work of external forces from FEA
* internal energy: strain from FEA outputs.
* Volume(mm^3): volume of the mandibles
* N of elements = number of tetrahedra of the mesh
* Adjusted internal energy (mJ/mm^3): standardized adjusted internal energy
* Mechanical Efficiency: standardized adjusted internal energy
* Extractor points 1-5: von Mises stress values at the corresponding extractor points
File: 1_R_code.r
Description: Code to run analyses of bite performance metrics (MANOVAs, correlations, phylodist, phylotree)
File: 2_R_code.r
Description: Code to generate morphospace and performance landscapes
File: 3_R_code.r
Description: Code to generate the simulated bite force plots
File: WIS_tree.tre
Description: Topology to generate the phylogenetic tree. Must be in the working directory when running "1_R_code.r"
File: WIS_ranges.txt
Description: Stratigraphic ranges for the taxa analyzed. Must be in the working directory when running "1_R_code.r"
Code/software
Software: RStudio (R v4.4)
Loaded packages are in the scripts and annotations help to reproduce the analyses step-by-step.
Access information
Other publicly accessible locations of the data:
- Additional 3D data of the mandibles are available on Morphosource, Sketchfab and Phenome10k
Data was derived from the following sources:
- Measurements from 3D models, photos and literature
- 3D models from Morphosource or own scans
