PhD: The late Silurian-early Devonian adaptive radiation (‘explosion’) of vascular plants

The origin of land plants and their invasion of the land is one of the most important events in the history of life on Earth. It had far-reaching consequences in terms of: (i) evolution (origin and diversification of one of the three kingdoms of multicellular life); (ii) environment (directly affecting all of the major geochemical cycles and hence atmospheric composition and climate). However, much remains to be discovered regarding this transformative evolutionary episode. Following the invasion of the land by plants in the Mid Ordovician vegetation remained diminutive, simple and of limited aerial coverage for at least 40 million years. It was not until the late Silurian that land plants began an adaptive radiation characterised by dramatic increases in size and disparity resulting in increased biodiversity and aerial/ecological coverage. This adaptive radiation is hypothesized to have been triggered by the evolution of vascular plants. This project will analyse the early land plant fossil record from the classic latest Silurian-earliest Devonian sequences of the Anglo-Welsh Basin. Evidence from dispersed spores will be used to quantitatively analyse changes in diversity and disparity and rates of evolutionary turnover. Evidence from in situ spores preserved in plant megafossils will be used to interpret the dispersed spore record in terms of the biological affinities of the plants. This will shed light on the tempo of the shift in dominance from stem group embryophytes (so-called cryptophytes) to vascular plants and their immediate precursors.

The research student will undertake fieldwork in the Anglo-Welsh Basin and be trained in both palynological and palaeobotanical processing and analytical techniques. Time will be spent working at the Natural History Museum, London (CASE partner) examining the extensive collections housed therein and working with experts from this institution.