The fossil record is not a faithful chronicle of the history of past life, but is instead beset by sampling and preservational biases that need to be accounted for if we are to understand biodiversity patterns in the past. Although many biases are well understood, and can be corrected for using a variety of statistical procedures, one which has not previously been investigated is a taxonomic identification bias.
The taxonomic identification bias arises from the potential for some taxa to be more readily identified because the bones on which their diagnostic characteristics are found are more likely to be preserved. This is important, because if a taxon can be identified, it is more likely to be described in the scientific literature and thus included in large databases, such as the Paleobiology Database from which many biodiversity studies derive their data.
The aim of this study is to investigate whether a taxonomic identification bias is present among meat-eating dinosaurs in the Upper Jurassic Morrison Formation, western USA. The Morrison Formation is a sequence of rocks deposited by rivers and on flood plains 155-145 million years ago. The formation has received much attention since the discovery of its diverse and well-preserved dinosaurian fauna in the latter part of the nineteenth century. Eleven meat-eating dinosaurs are currently recognised from the Morrison, but the well-known taxon Allosaurus is by far the most abundant, comprising 66% of reported finds. In this project, we test the hypothesis that the high abundance of Allosaurus is because it is more easily identified than other Morrison theropod taxa, since its diagnostic characteristics occur on bones more likely to be preserved.
Dinosaur bones preserved in a sandstone deposited by a river in the Upper Jurassic Morrison Formation near Capitol Reef National Park, Utah.
Picture: Susannah Maidment
This project runs from June 2017 to September 2017.
The objectives of this research are:
To follow on completion of the project
Dr Susannah Maidment
Mr Will Richardson (University of Brighton Undergraduate student)