Tom Green

University of Leicester


A hidden record of early animal evolution? Exploring the Cambrian diversity of acritarchs and small carbonaceous fossils


  • Dr Tom Harvey, University of Leicester
  • Professor Mark Williams, University of Leicester

PhD Summary

Acritarchs are organic-walled microfossils of unknown affinity, extracted using standard palynological laboratory techniques. In contrast, more gentle procedures yield larger, more delicate Small Carbonaceous Fossils (SCFs) that represent a range of organisms, including a diversity of animals. The two methodologies and datasets overlap and recent combined approaches have begun to shed light on the affinity and importance of acritarchs and SCFs in a pivotal interval in earth’s history, The Cambrian. This project will initially focus of the acritarch and SCF assemblage of the Forteau Formation, Newfoundland, Canada (Cambrian, Stage 4). Analysis of material from the Forteau has already yielded palynomorphs derived from Priapulid worms, arthropods, slug-like Wiwaxiids as well as several enigmatic problematica. The Forteau material offers an unrivalled opportunity to resolve affinities and ecologies of otherwise mysterious Cambrian microfossils. Any insights will enable us to constrain larger scale patterns in Cambrian diversity and ecology, reconstruct palaeo-plankton structure and tell us about how ecosystems responded to major evolutionary events.

Previous activity

Before my PhD I studied an MGeol degree in Geology with Palaeobiology at the University of Leicester. I’ve been interested in Cambrian fossils for several years, conducting my undergraduate dissertation on the taphonomy of the Burgess Shale, British Columbia, Canada. In my masters thesis I investigated the variety cuticular structures, attributable to Priapulid worms, in the Small Carbonaceous Fossil (SCF) assemblage of the Cambrian Deadwood Formation, Saskatchewan, Canada to track macroevolutionary trends in disparity. Between my masters and starting my PhD I’ve worked on a vineyard and as a cook and have travelled around Australia and South Africa.

Why did you choose doctoral research?

Throughout my degree I was fortunate enough to be able to get involved with research going on in the department at Leicester. Projects I was involved with included preparing shark dermal sample for analysing hydrodynamic properties and collecting paraconodont elements from the Alum shale, Sweden. In 2020 I was awarded a PALASS studentship to research dental microwear in treeshrews as a proxy for interpreting palaeodiet. These experiences along with my masters project fostered my passion for research.

Why did you choose CENTA?

I was attracted to CENTA because of the broad range of training opportunities they offer and fantastic links to institutions such as the Natural History Museum and the British Geological Survey. In addition to the draw of a funded opportunity to study a PhD title perfect for me.

Future plans

In future I am interested in continue in research. My PhD project in conjunction with CENTA training will provide me the opportunity to gain essential technical and research skills and to build my CV further enabling me to apply for future placements or jobs.