PhD: Spatio-temporal dynamics of the oldest deep-sea communities from the Ediacaran (~565 million years ago)

Brief summary:
This project will investigate the spatio-temporal dynamics of some of the first animals to ever have existed, those found in the Ediacaran time period 600 million years ago.
Importance of the area of research concerned:
Animals first appear in the fossil record during the Ediacaran time period (631-541 million years ago). It is during the Ediacaran animals evolved some of their most important traits: most obviously large body-size but also tissue-differentiation, mobility, bilateral symmetry and ecosystem engineering (reef-building). The study of Ediacaran organisms is fraught with difficulties because commonly-used morphological approaches have only limited use due to the unique anatomies of Ediacaran organisms. Fortunately, the preservation of Ediacaran fossils is exceptional with thousands of immobile organisms preserved where they lived under volcanic ash. Therefore, the position of the fossil on the rock surface encapsulates their entire life history: how they reproduced and how they interacted with each other and their environment (Mitchell et al. 2015). As such, ecological statistics provides a novel approach for investigating fundamental issues in early animal evolution.
Project summary :
Ediacaran beta diversity is exceptionally high, however the underlying mechanisms for this high diversity and differences between communities are not well understood. This project will investigate the spatio-temporal dynamics for the oldest deep-water Ediacaran communities, the Avalonian and determine the extent to which different communities represent different stages of ecosystem development and/or are determined by stochastic processes.
What will the student do?:
The student will analyse data from existing photographic and laser-scan data as well as their own fieldwork data to reconstruct maps of Avalonian Ediacaran communities (cf. Mitchell et al. 2019). These maps will then be used to extract the sizes, areal coverage (as a proxy for biomass) and taxonomic identification for all specimens. To determine how different taxa interact with each other, each community will be analysed using spatial point process analyses and Bayesian network inference. The relative maturity of the communities will be estimated using calculations of community biomass, population size distributions and number of reproductive events. These analyses will enable the comparison of how taxa interactions change with relative community maturity, enabling the student to determine the driving factors behind Avalonian Ediacaran community composition.
References - references should provide further reading about the project:
Mitchell, E. G., Kenchington, C. G., Liu, A. G., Matthews, J. J., & Butterfield, N. J. (2015). Reconstructing the reproductive mode of an Ediacaran macro-organism. Nature, 524(7565), 343.
Mitchell, E. G., Harris, S., Kenchington, C. G., Vixseboxse, P., Roberts, L., Clark, C., ... & Wilby, P. R. (2019). The importance of neutral over niche processes in structuring Ediacaran early animal communities. Ecology Letters 22(12) 2028-2038.
Clapham ME, Narbonne GM, Gehling JG. (2003) Paleoecology of the oldest known animal communities: Ediacaran assemblages at Mistaken Point, Newfoundland. Paleobiology. 29(4):527-44.