McDonald Honours Projects

Experimental evolution of an artificial microbiome on the plant root.

Background: Microbial communities comprised of many interacting species - including plants - sustain all ecosystems. Anticipating the disruptive effects of microbial adaptation in response to shifts in the environment, such as climate change and the use of new antibiotics, is an important goal. Experimental studies of evolution have provided insights into the speed of adaptive change, and its genetic causes, but have not considered the unique conditions experienced by microbes cohabiting with other species. Since the members of a microbial community are themselves part of the environment, the presence of one species will alter the selective pressures faced by their co-habiting species. This interaction between ecology and evolution, or eco-evolutionary feedback, means that adaptation to a given antibiotic, nutrient source or temperature will be quite different for a species evolving in isolation than for a species embedded within a microbial community.

Project Aims:  Our model system comprises a small plant growing in agar, providing nutrients for a community of microbes that live on the roots. We are trying to work out the rates and genetic mechanisms of adaptation for microbes co-evolving with other species within a community, and how to drive their evolution in different directions.  You will measure the phenotypes of the plant and microbes, and carry gather whole-genome DNA sequence data for all populations to determine the adaptive changes, as well as to unravel the molecular details of specific instances of co-evolution.

Techniques:  Short and long-read genome sequencing, bioinformatic genome assembly, experimental evolution and molecular biology, plant propogation.

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