skip to primary navigationskip to content
 

Evolutionary drivers and consequences of plant evolutionary radiations

Supervisor: Andrew Tanentzap

Reference code: B137

Importance of the area of research concerned: Predicting the conditions that allow species to proliferate in diversity is a central question in evolutionary biology and has practical implications for modern conservation.  In many parts of the world, recent and rapid radiations have accompanied the expansion of habitats due to climatic and geological changes (Linder 2008).  However, the importance of niche-based evolutionary processes in not only generating diversity, but also influencing ecological dynamics, remains understudied.

Project summary: The aims of this studentship are to test how different types of niche formation influence in situ diversification rates and how shifts in speciation-extinction dynamics drive the formation of different vegetation types.  Addressing the first aim involves adapting a widely-used mathematical model of adaptive evolution to track genetic and trait responses of individual plants over thousands of generations in response to different reproductive isolation scenarios (Gavrilets and Vose 2005).  This will generate hypotheses that we will test experimentally in the laboratory (e.g. Koeppel et al. 2013) using model organisms, and by comparing empirical data among lineages with different levels of diversity.  The second aim will be tackled with an extensive database of plant fossils and evolutionary ages.

What the student will do: The student will program the theoretical model and refine the research questions.  They will also design and execute the laboratory experiment, measuring genetic variation among populations and genes underlying trait differences.  They will then use phylogenetic comparative methods to reconstruct the evolutionary history of lineages with different diversity levels, and analyse temporal shifts in speciation and extinction on phylogenetic trees using established approaches.  Where needed, the student will estimate time-calibrated molecular phylogenies.

Training to be provided: The student will be given training in computer programming and statistical modelling (including phylogenetic analysis).  Although some prior experience in these areas is helpful, a greater emphasis will be placed on molecular biology skills and bioinformatics associated with the experimental work.  Instruction on experimental design and scientific writing will also be provided.

References:

  1. Gavrilets, S. & Vose, A. 2005. Dynamics patterns of adapative radiation. Proceedings of the National Academy of Sciences, vol. 102, pp.10840-10845.
  2. Koeppel, A.F. et al. 2013. Speedy speciation in a bacterial microcosm: new species can arise as frequently as adaptations within a species. International Society for Microbial Ecology Journal, vol. 7, pp.1080-1091.
  3. Linder, H.P. 2008. Plant species radiations: where, when, why? Philosophical Transactions of the Royal Society B, vol. 363, pp.3097-3105.