I’m going to discuss this a bit more clearly in an actual blog post, but for the meantime here is the Abstract for the MSci project which I will be working on until Janurary.
The completeness of the fossil record of pterosaurs: implications for their origin and diversity through the Mesozoic
Pterosaurs were a diverse group of flying archosaurs that formed an important component of terrestrial and marginal marine ecosystems throughout the Mesozoic, before their extinction at the Cretaceous/Paleogene boundary. Although a number of studies have examined pterosaur diversity throughout their 160 million year time span, including attempting to ameliorate for sampling biases in the fossil record, none of these analyses have considered the quality of the specimens themselves. Time intervals dominated by fragmentary and incomplete specimens may obscure macroevolutionary events such as radiations and extinctions, including clouding our understanding of the origin of pterosaurs, as well as hindering our ability to test for competitive replacements by other groups (e.g. birds).
The student will compile a dataset on the completeness of all pterosaur species, utilising a recently devised character completeness metric, and using The Paleobiology Database (PBDB) as a starting point for taxonomic data. This dataset will then be used to examine how pterosaur completeness varied through time, and statistical tests will be implemented to analyse whether there is any correlation with pterosaur diversity, sampling proxies (such as numbers of collections), and also fluctuations in sea level. Furthermore, the student will examine whether completeness varied between terrestrial and marginal marine environments. Lastly, comparisons will be made between pterosaur completeness and existing datasets for Mesozoic birds and sauropodomorph dinosaurs to investigate whether there are differences in completeness between small bodied animals with delicate skeletons (i.e. pterosaurs and birds) and large bodied robust forms (sauropodomorphs). Such comparisons will also help to understand the impact of Lagerstätten deposits on our reading of deep time diversity patterns.
This project will help shed new light on the evolutionary history of pterosaurs, as well as add new information to the growing body of work investigating the effect of sampling on our understanding of the fossil record. The student will gain firsthand experience of compiling a dataset based on using the literature and the PBDB, and will learn how to implement a number of statistical methods for analysing past diversity, as well as develop an understanding of the problems palaeobiologists face when attempting to investigate macroevolutionary patterns in the fossil record.