Data from: Electron backscatter diffraction (EBSD) analysis of maniraptoran eggshells with important implications for microstructural and taphonomic interpretations
Data files
May 22, 2019 version files 432.31 MB
-
10 Grain boundary maps.zip
9.50 MB
-
Contrast maps.zip
9.52 MB
-
EBSD raw data for materials.zip
72.80 MB
-
Fossil eggshell SEM images.zip
107.71 MB
-
Misorientation (For Figure 9).zip
1.41 MB
-
Misorientation (For Figure S2 and Table S2).zip
122.42 KB
-
Modern avian eggshell SEM images.zip
130.37 MB
-
Raw data converted to Text files.zip
81.15 MB
-
README_for_Supplementary Figures S1-S4.docx
14.45 KB
-
README_for_Supplementary Tables S1-S3.docx
14.45 KB
-
Supplementary Figures S1-S4.zip
19.64 MB
-
Supplementary Tables S1-S3.zip
57.06 KB
Abstract
Electron backscatter diffraction (EBSD) is a useful tool for gathering crystallographic information from carbonate biominerals because it maps out the orientation of crystal grains very precisely. EBSD has become popular in invertebrate palaeontology but its application in vertebrate palaeontology remains limited. However, the study of fossil eggshells is a field where EBSD has wide potential applicability and provides a quantitative approach to fossil eggshell research as well as new qualitative data. Here we analyse fossil and extant maniraptoran dinosaur eggshells using EBSD analysis emphasizing four different aspects. The mapping imaging clarifies previously ambiguous characters such as squamatic ultrastructure and allows a more objective evaluation of avian and non‐avian maniraptoran eggshell. In particular, our results imply that the presence of an external zone in the manirpatoran eggshell is not diagnostic of avian eggshell. EBSD analysis can be also used for differentiating true pore canals from cracks in the eggshell radial section, thereby determining the biological genuineness or otherwise of a pore‐like structure. Finally, the misorientation angle distribution of the material shows a clear dichotomy that may reflect reproductive brooding strategy, although further studies on contact incubation of palaeognaths and neognaths are needed to confirm this.