About Me


I am a plant microbial ecologist currently working at Bangor University as part of the FUTURE OAK project. I am interested in the interactions between plants and their microbiomes, the complex collection of micro-organisms, such as bacteria and fungi, that inhabit the tissues of their host plants. In particular, I am interested in mutualism - interactions between the host and microbe that benefit both parties. These interactions can involve the provision of vital nutrients, stimulation of immune responses, and protection from pathogens. In particular, I am interested in how these beneficial interactions affect the ecology of the host plant - for example, how the ecology of these microbial species can affect disease prevalence within host populations, host geographic distribution, and the evolutionary responses of hosts to selection pressures.

I also have a strong interest in statistics and data analysis, particularly in mixed modelling and the analysis of multivariate data, particularly ecological community data. I am currently teaching myself to apply these concepts in a Bayesian framework, and am learning about causal inference. I am keen to help make these conceptual frameworks more common in Ecology and Evolutionary Biology, and to help share them through teaching, currently informally.

Current projects

I am currently working as part of the FUTURE OAK project at Bangor University. Acute Oak Decline (AOD) is a major current threat to oak trees in the UK, spreading widely across south and central England, which can result in tree death within five years of symptom onset. The disease is caused in part by a multispecies “pathobiome” of pathogenic bacteria, which work in concert to cause lesions and stem bleeding on affected trees. However, trees are also host to a wide array of other micro-organisms (the oak microbiome), many of which are beneficial for tree health. The aim of the FUTURE OAK project is to characterise the oak microbiome on oak trees across the UK, at sites with and without AOD, in order to find species of micro-organisms which may provide protection against AOD. We then plan to use these species to engineer a microbial biocontrol treatment to try and reduce the spread of this disease.

Past projects

I previously completed my PhD at the University of Edinburgh on the evolutionary ecology of interactions between Scots pine (Pinus sylvestris L.) and its ectomycorrhizal fungal symbionts. Ectomycorrhizal fungi are important symbiotic partners of pine, providing benefits such as nutrient provision and protection from disease in exchange for photosynthetic sugars. Previous work has shown that both the host and its fungal partners can evolve to maximise the benefits arising from these interactions, and that this may result in local adaptation. Using the Caledonian pinewoods in Scotland as a model system, I looked for evidence for genetic variation among and within populations of Scots pine in terms of their interactions with fungi, both in terms of growth and the communities of fungi colonising them. While I found evidence for genetic variation in terms of growth, I found no evidence for local adaptation, and no evidence for genetic variation in fungal community composition.



In chronological order:

  1. Downie, J., Taylor, A.F.S., Iason, G., Moore, B., Silvertown, J., Cavers, S., Ennos, R., 2021. Location, but not defensive genotype, determines ectomycorrhizal community composition in Scots pine (Pinus sylvestris L.) seedlings. Ecology and Evolution 11, 4826–4842. https://doi.org/10.1002/ece3.7384

  2. Downie, J., Silvertown, J., Cavers, S., Ennos, R., 2020. Heritable genetic variation but no local adaptation in a pine-ectomycorrhizal interaction. Mycorrhiza. https://doi.org/10.1007/s00572-020-00941-3