Project highlights

  • Gain expertise in the generation of high fidelity 3D digital data sets for fossils
  • Conduct fieldwork at key palaeontological sites in the USA and Europe
  • Develop a new model for the palaeoecology and evolution of pterosaurs in terrestrial environments


Pterosaurs, Mesozoic flying reptiles, were long considered to have been almost exclusively confined to aerial niches, with only limited mobility when on the ground (Unwin, 2005). Two lines of evidence have challenged this view: (1) a rapidly accumulating and increasingly diverse pterosaur track record (pteraichnites) that spans more than 80 million years; (2) digital modelling, based on skeletal remains and tracks, of pterosaur’s terrestrial locomotory abilities. These studies show that pterosaurs used a flat-footed, four-legged, but nevertheless highly efficient, stance and gait. They have also uncovered some unexpected behaviours, such as a quadrupedal launch, that point to a far more effective ability to take-off and land than previously suspected. These new findings suggest that pterosaurs played a much bigger role in Mesozoic terrestrial communities than previously realised (Witton, 2013), but the extent and evolutionary significance of this phenomenon remains unclear and controversial.

This project will use a multidisciplinary approach to reassess the contribution of pterosaurs to Mesozoic continental biotas and their impact on co-evolving groups such as early birds (Benson et al, 2014). New techniques including photogrammetric ichnology will form part of the first systematic analysis of the pterosaur track record. This work will generate a range of data sets that capture fine detail of prints and tracks that can be combined with contextual data including sedimentology, stratigraphy and associated ichnological and body fossil evidence.

These data sets will underpin three complementary strands of the PhD: (1) reconstruction of the locomotory styles and abilities of pterosaurs (stance, gait, speed, take-of and landing modes) based on key sites in the USA and Europe. (2) The first comprehensive integration of the ichnological and body fossil record of pterosaurs via 3D digitisation of prints and well preserved skeletal remains. (3) Identification and reconstruction of specific behaviours (e.g. feeding, flocking) set within current interpretations of the palaeoenvironments in which they occurred.

Results of these three studies will be combined with data on the relationships and temporal and biogeographic distribution of pterosaurs to determine the extent to which they contributed to Mesozoic terrestrial biotas and influenced the evolution of contemporaneous groups such as birds.



University of Leicester


  • Organisms and Ecosystems


Project investigator

  •  David Unwin, University of Leicester (



  • Mark Purnell, University of Leicester
  • Richard Butler, University of Birmingham
  • Peter Falkingham, Liverpool John Moores University
  • Brent Breithaupt, Bureau of Land Management, USA

How to apply


New approaches to collecting and interpreting prints and tracks including photogrammetry, pioneered by Breithaupt (e.g. Lockely et al., 2016) will be used to generate high fidelity 3D digital data sets based on key sites in the USA (Wyoming), France (Crayssac) and Spain (Asturias) that contain multiple individuals and exceptionally high quality impressions (Unwin, 2005; Witton, 2013). Identification of track-makers will take advantage of our rapidly expanding knowledge of pterosaur skeletal anatomy and the possibility of highly accurate comparisons between digitised sets of tracks and 3D skeletal elements of the hand and foot. This approach will be located within a well established phylogenetic framework developed by Unwin and others. Digital models have been shown to be highly effective at constraining likely stance, gait, velocity and manoeuvrability for extinct taxa (Falkingham and Gatesy, 2014) and will be applied here to both ichnological and skeletal data. The reconstruction of behaviours, palaeoenvironments and the evolutionary history of pterosaur terrestrial palaeoecology, supervised by Butler, will use quantitative approaches set within a phylogenetic framework.

Training and skills

Specialist training will include identification and interpretation of pterosaur tracks and skeletal anatomy, supervised by Unwin, photogrammetry as applied to palaeoichnology, supervised by Breithaupt and Butler, and analysis of locomotion, supervised by Falkingham. The student will also receive training, supervised by Butler, in data base construction with a particular emphasis on the statistical analysis of palaeontological data.

Partners and collaboration

Dr Unwin has 30+ years’ experience of research on pterosaurs, holds extended datasets on pterosaur skeletal anatomy, and palaeoichnology and has access to key specimens that will be studied during this project. Prof Purnell has extensive experience of research and management of palaeontological projects. Dr Falkingham has worked on fossil footprints for over a decade, using computational techniques including simulation (FEA, DEM, MBD) and digitization (laser scanning, photogrammetry) to study locomotion and footprint formation. Prof Butler has published widely on fossil reptiles, including pterosaurs, and has extensive experience in the application of quantitative approaches to analysis of palaeontological data. Dr Breithaupt has pioneered the development of photogrammetric ichnology, including its application to pterosaur tracks.

Further details

M. Unwin
University of Leicester,
19 University Road, Leicester LE1 7RF
Tel: +44 116 252 3947

Possible timeline

Year 1

Familiarisation with literature, existing datasets and palaeoichnological techniques including photogrammetry. Fieldwork in Spain and France to collect pterosaur track data. Analysis of these data. Presentation at PalAss (UK) and SVPCA (UK).

Year 2

Fieldwork in the USA to collect pterosaur track data. Continued analysis of all track data and integration with body fossil record. Analysis of pterosaur locomotory styles. Publication and presentation at SVPCA (UK), EAVP (Europe).

Year 3

Synthesis of results on locomotory abilities, behaviours and palaenvironments. Develop evolutionary history of pterosaurs in terrestrial environments. Publication and presentation at SVPCA (UK), SVP (USA). Write and submit thesis.

Further reading

Benson, R.B.J. et al. 2014. Competition and constraint drove Cope’s rule in the evolution of giant flying reptiles. Nature Communications, 5, 3567, doi: 10.1038/ncomms4567.

Falkingham, P.L. & Gatesy S.M. 2014. The birth of a dinosaur footprint: Subsurface 3D motion reconstruction and discrete element simulation reveal track ontogeny Proceedings of the National Academy of Sciences 111, 18279-18284.

Lockley, M.G. et al. 2016. Theropod courtship: large scale physical evidence of display arenas and avian-like scrape ceremony behaviour by Cretaceous dinosaurs. Nature: Scientific Reports, 6, nb 18952, doi:10.1038/srep18952.

Unwin, D.M. 2005. The Pterosaurs from Deep Time. Pi Press, New York, 347pp.

Witton, M.P. 2013. Pterosaurs: natural history, evolution, anatomy. Princeton University Press. 291pp.


In the event that Covid-19 is still an issue in late 2021/early 2022 the main impact on the project would be to delay fieldwork planned for summer 2022. This would be moved to 2023 with little long term impact on the project. If necessary, all other activities planned for Year 1 of the project (mainly revolving around existing digital resources) could be completed remotely and would not need access to campus facilities.