Evidence for dromaeosaurid scavenging on Albertosaurus (Dinosauria: Tyrannosauridae)
Data files
Jul 15, 2026 version files 812.69 KB
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README.md
4.47 KB
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SuppDataA_ALBMeanAlveolarLengthData.csv
5.59 KB
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SuppDataA_AlveolarSpacingData.csv
61.22 KB
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SuppDataA_BiPlotDataSkulls.csv
3.99 KB
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SuppDataA_BiPlotDataTeeth.csv
46.63 KB
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SuppDataA_DenticleSpacingData.csv
53.70 KB
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SuppDataA.xlsx
115.15 KB
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SuppDataB.pdf
485.73 KB
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SuppDataC_Denticle_Spacing_R_Code.R
12.31 KB
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SuppDataD_Alveolar_Spacing_R_Code.R
23.88 KB
Abstract
Direct evidence of trophic interactions in the fossil record (e.g., feeding traces, stomach contents) are key to understanding predator-prey relationships between extinct species and reconstructing ancient ecosystems. Recently discovered associated cranial material of an immature Albertosaurus sarcophagus from the Upper Cretaceous (uppermost Campanian-Maastrichtian) Horseshoe Canyon Formation (Alberta, Canada), represents the smallest associated Albertosaurus skull discovered to date. Osteohistological analysis of an associated limb element indicates the individual was at least eight years old at time of death. The specimen preserves two sets of unhealed tooth marks on the mandible. Tooth and denticle mark spacings were studied to identify the potential trace maker. We apply a new method to account for rake angle in tooth and denticle marks to improve the estimation of inter-and intra-mark spacing. Our results reveal that the tooth marks are most consistent with those produced by dromaeosaurids. Given that the tooth marks display no signs of healing, they represent the first documented evidence of a dromaeosaurid feeding/scavenging on tyrannosaurids. Dromaeosaurs and immature tyrannosaurids likely participated in reciprocal predation/scavenging within the carnivorous dinosaur guild. The Albertosaurus specimen, and its preserved traces, expands our understanding of dromaeosaurid diet and interspecific interactions, and provides insight into the skull morphology of young Albertosaurus individuals.
Dataset DOI: 10.5061/dryad.x69p8d006
Description of the data and file structure
This supplementary dataset contains additional measurements for TMP 2022.007.0040, and measurements of alveolar and denticle spacing of potential trace maker taxa for the tooth marks preserved on TMP 2022.007.0040. The dataset can be used as a base for further trace maker identification studies, and the statistical analyses can be followed through the use of the R code provided.
Files and variables
File: SuppDataA.xlsx
Description: Contains measurements for trace maker denticle spacing, alveolar spacing, and paired denticle/alveolar spacing to create Figure 11 in Doyon et al. (2026). Also contains comparative Albertosaurus data for TMP 2022.007.0040. Includes four Excel Worksheets. Use 'Denticle Spacing Data' worksheet to run SuppDataC in R, and use 'Alveolar Spacing Data' worksheet to run SuppDataD in R. Empty cells indicate insufficient information or unapplicable measurement. All measurements are in mm.
Each individual worksheet 'Denticle Spacing Data', 'Alveolar Spacing Data', 'BiPlot Data', and 'ALB Mean Alveolar Length Data', is included below as seperate '.csv' files.
Microsoft Excel can be used to view SuppDataA.
File: SuppDataA_DenticleSpacingData.csv
Description: A subset of 'SuppDataA'. Contains measurements for trace maker denticle spacing. Excludes any additional notes or titles that are present in the 'SuppDataA.xlsx' file.
File: SuppDataA_AlveolarSpacingData.csv
Description: A subset of 'SuppDataA'. Contains measurements for trace maker alveolar spacing. Excludes any additional notes or titles that are present in the 'SuppDataA.xlsx' file.
File: SuppDataA_BiPlotDataTeeth.csv
Description: A subset of 'SuppDataA'. Contains paired measurements for trace maker fore-aft base length of tooth and denticle spacing for isolated teeth. Excludes measurements of specimens for which alveolar spacing is available. Excludes any additional notes or titles that are present in the 'SuppDataA.xlsx' file.
File: SuppDataA_BiPlotDataSkulls.csv
Description: A subset of 'SuppDataA'. Contains paired measurements for trace maker alveolar spacing and denticle spacing for cranial elements. Excludes measurements of specimens with only isolated teeth. Excludes any additional notes or titles that are present in the 'SuppDataA.xlsx' file.
File: SuppDataA_ALBMeanAlveolarLengthData.csv
Description: A subset of 'SuppDataA'. Contains mean alveolar length measurements for Albertosaurus specimens. Excludes any additional notes or titles that are present in the 'SuppDataA.xlsx' file.
File: SuppDataB.pdf
Description: Contains additional figures and measurements of TMP 2022.007.0040, calculations for size and age estimates of TMP 2022.007.0040, and data for the application of the correction method to examples in the literature. Includes figure of additional teeth belonging to TMP 2022.007.0040, and contains figure of tooth mark spacing correction applied to literature. Includes tables with measurements of the tooth marks on TMP 2022.007.0040 and examples in the literature, used to create Figures 9–11, and 13.
Any PDF viewer can be used to view SuppDataB.
File: SuppDataC_Denticle_Spacing_R_Code.R
Description: Contains the R Code used to compare denticle spacing of potential trace maker taxa and the denticle mark spacing on TMP 2022.007.0040. Instructions on what supplementary data to use from SuppDataA are included in the first six lines of code. Import .csv data into RStudio to run analysis. Used to create Figure 9 in Doyon et al. (2026).
R is required to open SuppDataC_Denticle_Spacing_R_Code.R.
File: SuppDataD_Alveolar_Spacing_R_Code.R
Description: Contains the R Code used to compare alveolar spacing of potential trace maker taxa and the tooth mark spacing on TMP 2022.007.0040. Instructions on what supplementary data to use from SuppData A are included in the first six lines of code. Import .csv data into RStudio to run analysis. Used to create Figure 10 in Doyon et al. (2026).
R is required to open SuppDataD_Alveolar_Spacing_R_Code.R.
Code/software
R statistical Program (R version 4.2.2) with RStudio (version 2022.12.0+353).
