I inferred time-calibrated phylogenies for the tropical plant genus Ipomoea, and used this a a framework to address theoretical questions about the kinds of information about evolution that can be derived from a phylogeny constructed from genomic sequence data. I focused particularly on understanding temporal patterns of evolutionary diversification, and showed that there are fundamental limitations to the precision with which inferences can be made - even when analysing genomic scale datasets. These limitations have been overlooked in previous studies, resulting in inferences that are misleadingly precise. Nonetheless, I showed that when specific hypotheses are addressed, novel insights can be derived from time calibrated phylogenies. In the context of Ipomoea we showed that the sweet potato (Ipomoea batatas) evolved in pre-human times, and that there are marked increases in speciation rates in specific clades within Ipomoea that are of a scale equivalent to some of the most iconic radiations in the plant kingdom.
Current Research/employment
Phylogenomics and Macroevolution of Saxifraga. I have been working on building a phylogeny for Saxifraga, and estimating a timescale for the evolution of this alpine plant genus. This will be used as a basis to investigate how species of Saxifraga disperse between mountain ranges, and adapt to different habitats. I am also working on theoretical aspects of divergence time estimation, and more generally determining the types of information about evolution that can be derived from phylogenies.
Was your D.Phil relevant to what you are doing now?
