TY - JOUR
T1 - The stability of dinosaur communities before the Cretaceous–Paleogene (K–Pg) boundary: A perspective from southern Alberta using calcium isotopes as a dietary proxy
AU - Martin, Jeremy E
AU - Hassler, Auguste
AU - Montagnac, Gilles
AU - Therrien, François
AU - Balter, Vincent
N1 - J.E. Martin thanks D. Henderson for help and support during his visit to Royal Tyrrell Museum of Palaeontology (RTMP), Drumheller, Alberta, Canada, and Dinosaur Provincial Park as well as D.B. Brinkman and B. Strilisky at RTMP for facilitating access to the collections. We thank F. Arnaud-Godet and P. Télouk for assistance with the concentration and isotopic analyses, B. Reynard for sharing the data set used inFigure 1B, and S. Martin for providing the Crocodylus tooth from la Ferme aux Crocodiles, Pierrelatte, France, used for the Raman analysis. The dinosaur outlines in Figures 1 and 4 were retrieved from www.phylopic.org and were contributed by A. Farke, E. Willoughby, C. Dylke, M. Ruiz-Villareal, and M. Dempsey. We thank them for transferring their work to the public domain or through a creative commons license. Geochemical analyses conducted in this work were partly supported by the Agence Nationale de la Recherche (SEBEK project no. ANR-19-CE31-0006-01 to J.E. Martin), by the Centre National de la Recherche Scientifique, Institut National des Sciences de l’Univers (CNRS INSU), and by École Normale Supérieure de Lyon (ENS Lyon), Lyon, France. RTMP provided authorization for specimen sampling and supported fieldwork at Dinosaur Provincial Park. The final version of this work benefited from the comments of Editor R. Strachan, Associate Editor B. Pratt, as well as two anonymous reviewers.
PY - 2022/9/1
Y1 - 2022/9/1
N2 - Reconstructing dinosaur trophic structure prior to the Cretaceous–Paleogene (K–Pg) boundary may provide information about ecosystem organization and evolution. Using calcium isotopes, we investigate preserved biogenic isotope compositions in a set of dinosaur teeth from three continental formations from Alberta, Canada, to assess latest Cretaceous food web structure. Tooth enamel δ44/42Ca values are presented for tyrannosaurids (n = 34) and potential large herbivorous prey (n = 42) in the upper Campanian Dinosaur Provincial Park Formation, upper-most Campanian–Maastrichtian Horseshoe Canyon Formation, and upper Maastrichtian–lower Paleocene Scollard Formation, spanning the last ~10 m.y. of the Cretaceous. The influence of diagenesis is assessed in a subset sample through major and trace elemental concentrations and ultraviolet (UV) Raman spectra, which provides a framework for interpreting calcium isotope values. In the Dinosaur Park Formation, hadrosaurid δ44/42Ca values are systematically heavier than ceratopsid values, a difference that is interpreted to reflect niche partitioning among megaherbivores. Tyrannosaurid δ44/42Ca values are scattered but on average, they are 44Ca-depleted relative to herbivorous dinosaurs in all three formations. As interpreted from the Dinosaur Park data set, tyrannosaurids may have preferentially fed on hadrosaurids. These analyses offer possibilities for testing whether trophic structure among non-avian dinosaur ecosystems changed several millions of years prior to the K–Pg boundary.
AB - Reconstructing dinosaur trophic structure prior to the Cretaceous–Paleogene (K–Pg) boundary may provide information about ecosystem organization and evolution. Using calcium isotopes, we investigate preserved biogenic isotope compositions in a set of dinosaur teeth from three continental formations from Alberta, Canada, to assess latest Cretaceous food web structure. Tooth enamel δ44/42Ca values are presented for tyrannosaurids (n = 34) and potential large herbivorous prey (n = 42) in the upper Campanian Dinosaur Provincial Park Formation, upper-most Campanian–Maastrichtian Horseshoe Canyon Formation, and upper Maastrichtian–lower Paleocene Scollard Formation, spanning the last ~10 m.y. of the Cretaceous. The influence of diagenesis is assessed in a subset sample through major and trace elemental concentrations and ultraviolet (UV) Raman spectra, which provides a framework for interpreting calcium isotope values. In the Dinosaur Park Formation, hadrosaurid δ44/42Ca values are systematically heavier than ceratopsid values, a difference that is interpreted to reflect niche partitioning among megaherbivores. Tyrannosaurid δ44/42Ca values are scattered but on average, they are 44Ca-depleted relative to herbivorous dinosaurs in all three formations. As interpreted from the Dinosaur Park data set, tyrannosaurids may have preferentially fed on hadrosaurids. These analyses offer possibilities for testing whether trophic structure among non-avian dinosaur ecosystems changed several millions of years prior to the K–Pg boundary.
UR - http://dx.doi.org/10.1130/b36222.1
U2 - 10.1130/b36222.1
DO - 10.1130/b36222.1
M3 - Article
SN - 0016-7606
VL - 134
SP - 2548
EP - 2560
JO - Geological Society of America Bulletin
JF - Geological Society of America Bulletin
IS - 9-10
ER -