Using the Fossil Record of Horned Dinosaurs to Test Hypotheses of Environmental and Ecological Associations in an Extinct Lineage

Location

Room 2905 B

Session Format

Paper Presentation

Research Area Topic:

Natural & Physical Sciences - Geology, Geography and GIS Systems

Abstract

In our continuing endeavors to understand the role ecology plays in evolution, the fossil record provides us the data to view macroevolutionary patterns through the lens of deep time. This perspective gives paleontologists the unique opportunity to tell the story of an evolving lineage from its origins to its extinction and how it responded and adapted to changing conditions. Ceratopsians, or horned dinosaurs, represent a diverse and widespread clade of non-avian herbivorous dinosaurs that are known from the fossiliferous formations of North America and Asia. The coexistence of multiple groups, both large and small-sized, in North America raises intriguing questions about ecological segregation, habitat preference, and the role functional traits played in niche partitioning. To test for this, I created a comprehensive database of fossil occurrences (49 genera) from the Paleobiology Database and a review of primary literature. Using published interpretations of the dinosaur fossil-bearing formations, I was able to characterize three environmental variables: temperature, precipitation, and paleoenvironment. For each genus, I assigned a rank score corresponding to its association with a given variable in a given formation. I then tested for environmental differences between three lineages: small-bodied basal species, large-bodied centrosaurines, and large-bodied chasmosaurines. Results indicated statistically significant differences between the three groups. While the small-bodied species seemed to be more associated with drier environments that were further away from the coasts, the large-bodied forms (chasmosaurines and centrosaurines) seemed to be more associated with swampy, coastal environments. Further partitioning among the large-bodied forms also indicates that centrosaurines might have been more associated with more temperate climates than the chasmosaurines. These results provide environmental and ecological context for answering additional questions regarding the evolutionary paleoecology of these dinosaurs and whether or not morphological traits (e.g. horns and frills, dentition) or other features (e.g. body size) were a result of adaptations to changing environmental conditions.

Presentation Type and Release Option

Presentation (Open Access)

Start Date

4-16-2016 1:30 PM

End Date

4-16-2016 2:30 PM

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Apr 16th, 1:30 PM Apr 16th, 2:30 PM

Using the Fossil Record of Horned Dinosaurs to Test Hypotheses of Environmental and Ecological Associations in an Extinct Lineage

Room 2905 B

In our continuing endeavors to understand the role ecology plays in evolution, the fossil record provides us the data to view macroevolutionary patterns through the lens of deep time. This perspective gives paleontologists the unique opportunity to tell the story of an evolving lineage from its origins to its extinction and how it responded and adapted to changing conditions. Ceratopsians, or horned dinosaurs, represent a diverse and widespread clade of non-avian herbivorous dinosaurs that are known from the fossiliferous formations of North America and Asia. The coexistence of multiple groups, both large and small-sized, in North America raises intriguing questions about ecological segregation, habitat preference, and the role functional traits played in niche partitioning. To test for this, I created a comprehensive database of fossil occurrences (49 genera) from the Paleobiology Database and a review of primary literature. Using published interpretations of the dinosaur fossil-bearing formations, I was able to characterize three environmental variables: temperature, precipitation, and paleoenvironment. For each genus, I assigned a rank score corresponding to its association with a given variable in a given formation. I then tested for environmental differences between three lineages: small-bodied basal species, large-bodied centrosaurines, and large-bodied chasmosaurines. Results indicated statistically significant differences between the three groups. While the small-bodied species seemed to be more associated with drier environments that were further away from the coasts, the large-bodied forms (chasmosaurines and centrosaurines) seemed to be more associated with swampy, coastal environments. Further partitioning among the large-bodied forms also indicates that centrosaurines might have been more associated with more temperate climates than the chasmosaurines. These results provide environmental and ecological context for answering additional questions regarding the evolutionary paleoecology of these dinosaurs and whether or not morphological traits (e.g. horns and frills, dentition) or other features (e.g. body size) were a result of adaptations to changing environmental conditions.