Fellowship: Adaption in complex senarios - Dr S Collins

This fellowship addressed fundamental questions relevant to evolutionary theory and has practical applications to climate change biology: how are the dynamics and outcomes of adaptation influenced by the presence of constantly changing environments or competition? The main aim was to first use laboratory experiments to test the results of simulation studies and to empirically test the role of competition in adaptive outcomes. A secondary aim was to develop a laboratory model system with a natural counterpart for examining microbial responses to global change.

One of the crucial elements of this work is that it established explicit (and where appropriate, quantitative) comparisons between community ecology, population genetic and experimental evolution methodologies.

Microbes can evolve quickly - in days or weeks. I'm interested in how green microalgae might evolve in response to climate change, particularly the high carbon dioxide conditions associated with ocean acidification. This collection of projects tied evolution (genetic change within populations) to ecology (changes in the environment around those organisms). It looked at how evolution differs when environments change quickly vs slowly and found that populations could evolve more when environmental change was slow. I also showed that evolving to successfully outcompete other algae was most likely in populations that were unable to adapt to changes in carbon dioxide. In addition, I worked directly with oceanographers to make sure that the tools of experimental evolution were used for marine experiments, and many of those experiments started during this fellowship are being published this year.

1. I produced empirical evidence that slower rates of environmental change fundamentally affect adaptive outcomes and dynamics, resulting in populations that are better adapted than those exposed to rapid changes of the same magnitude. 2. I published a quantitative framework that uses the Price equation to partition physiological, ecological, and evolutionary responses to changed environments, 3. I published an empirical study showing how competition between lineages and genetic adaptation within lineages interact when the two occur simultaneously, analysed in part using the framework from (2.). Lineages that were able to adapt to abiotic change were poor competitors so that communities subjected to environmental change were dominated by the least-adapted lineages. This challenges conventional predictions that lineages that adapt most to new environments will increase in frequency in those environments. 4. I have made tools directly available to oceanographers by publishing in oceanography journals , and was invited to speak at the Gordon conference for marine microbes (summer 2010), where I established several new collaborations. 5. Finally, I have characterized the algal communities in and around 3 independent CO2 springs,