Ecological Modelling PhD: How Flow Shapes Microbe–Virus Coevolution

Ecological Modelling PhD: How Flow Shapes Microbe–Virus Coevolution

Quick Decision

Promising, with important scientific and practical questions still open. This computational PhD brings together physics, microbial evolution and marine ecology. It asks how flow-driven separation changes the shared evolutionary history of microbes and viruses: whether prior host–virus interactions shape encounters with new partners, how long that influence lasts, and what happens when descendants meet again. The proposed work progresses from individual-based simulations in a simple flow field to larger, ocean-like fields, with analytical calculations, machine learning and a hybrid model that combines concentration-based efficiency with agent-level stochasticity. The Exeter EPSRC Doctoral Landscape Award page lists a September 2027 entry call and a midday 8 December 2026 deadline. The project PDF names a Physics PhD and states no additional project-specific entry requirements. (official project description, Exeter award page, Ref 6022)

The project pairs a focused scientific question with a concrete methods challenge: preserve individual stochastic effects without making large, complex simulations prohibitively expensive. Before applying, ask which organism pair and flow fields will anchor the models, how results will be validated, and how supervision will be divided. Funding is competitive; the published 2026/27 stipend is a reference benchmark rather than a confirmed 2027/28 rate, and official Exeter pages disagree on the reference deadline. Before applying, confirm the reference date, exact project registration/start date, and the supervisors' intended model and validation plan.

Research Problem and Doctoral Work

What Is Unsolved and Why It Matters

In the project's model of coevolution, a microbial host changes in response to viral infection and the virus in turn adapts to host defences. Flow can separate these partners before either lineage goes extinct. Their descendants may continue evolving in isolation and encounter one another again later. The project therefore asks how a shared evolutionary past shapes new interactions and how long that past leaves a measurable signature. It targets a gap between two bodies of work: spatial or motile systems show that movement and structure can alter host–phage dynamics, while marine ecology supplies relevant environmental context, but the combined sequence of coevolution, flow-driven separation, isolated evolution and re-encounter remains poorly characterized.

Recent evidence makes the question timely without answering it. A 2026 study observed long-distance transport of lytic phage infection with migrating bacterial fronts and developed a PDE model for that pattern. Its authors explicitly left bacterial resistance evolution and phage counterdefence out of the model, so it is adjacent evidence for transport rather than a demonstration of coevolution under oceanic advection. (2026 study) Experiments in spatially structured environments have produced multiple bacterial–phage diversification cycles, while a separate marine Aeromonas study tracked phage resistance and host-fitness trade-offs over 180 days. Neither tested the proposed flow and re-encounter sequence. (structured coevolution study, marine Aeromonas study)

Work, Methods, and Potential Outputs

The advertised work follows a bottom-up progression:

1. Build agent-based simulations in a prototypical flow field.
2. Use those simulations to test biological hypotheses about how flow changes microbial–viral coevolution, including separation, memory persistence and descendant re-encounter.
3. Add analytical calculations and machine learning as supporting tools.
4. Extend and test the findings in larger systems with more complex fields intended to mimic oceanic conditions.
5. Develop a hybrid modeling approach that retains the computational efficiency of concentration-based models and the stochasticity of individual-based models.

As described, this is primarily a modeling and simulation project. Ask whether laboratory work or experimental validation is planned, which microbial system and ocean-like flow field will anchor the models, and what data will be available for calibration. Those choices matter: flow profile, encounter rates, population density and timescale can change whether an agent-based representation is necessary and how a hybrid model should switch between scales.

The hybrid-method challenge is supported by the Bath collaboration. Yates's group develops methods that connect stochastic, individual-level descriptions with deterministic continuum models. A 2025 paper by Cameron, Smith and Yates adaptively used a discrete stochastic reaction–diffusion model at low concentrations and continuum equations at higher concentrations, with tests on diffusion, morphogen gradients and travelling waves. That is a close methodological precedent, not proof that the same method will work for evolving viruses in ocean-like flow. (Yates research profile, 2025 hybrid-model paper)

Possible analytical angles—not promised deliverables—include measuring how long a host–virus history remains predictive as separation time increases, separating the effects of encounter frequency from coevolution, and identifying where individual-level noise changes outcomes enough to justify the hybrid model. The project needs an explicit validation target to make those comparisons convincing.

School, Programme and Field Context

The project PDF identifies the potential degree as a PhD in Physics and places the research in Exeter's Department of Physics and Astronomy and Living Systems Institute. The University of Exeter is therefore the confirmed institution for study and degree; Bath is named as a collaborator through Kit Yates. Ask whether Bath has any registration or joint-degree role. The LSI integrated PhD programme brings students from physics, mathematics, computational science, engineering and the life sciences together through interdisciplinary modules, workshops, advisory thesis committees and peer research discussions. Exeter's Physics PhD page describes second-supervisor or mentor support, subject training and seminars. (Physics PhD programme, LSI PhD programme)

Exeter's REF 2021 submission for UoA 9 Physics received a profile of 48% 4-star and 45% 3-star research. This is unit-level evidence from the 2021 assessment, not a rating of this project. The university's overall position is 136 in the QS World University Rankings 2027 and =170 in the THE World University Rankings 2026; these are overall institutional rankings, not Physics subject ranks. The more relevant signal is the LSI's stated integration of mathematical and physical theory with experimental biology and the Moebius Group's work on environmental effects in biological dynamics. (REF 2021 results, Exeter ranking table, LSI overview)

Exeter allows up to four years of full-time PhD registration, while the EPSRC DLA advertises up to 3.5 years of funding. Ask Exeter for the expected submission date and what support applies if registration continues after funding ends. The DLA call targets September 2027 entry; confirm the project's precise registration date. (Exeter degree-duration rules, EPSRC DLA information)

Supervisor and Lab Assessment

Supervisor Research Directions

Wolfram Moebius leads the project. His group studies how the physical world shapes biological dynamics, with a focus on environmental effects on populations expanding into new habitats. It uses physics-derived models, simulations and quantitative measurements; its stated model system includes T7 bacteriophage spreading on E. coli. This is a direct conceptual match for combining physical transport with phage–host evolution. (Moebius Group)

Daniel Kattnig is described in the project PDF as a physicist with expertise in large-scale simulations. The public theoretical-physics page highlights his research on magnetosensitivity and radical-pair dynamics. That work demonstrates a computational and physical-science background, but it does not establish his role in microbial ecology. Ask what he will contribute to model design, numerical methods and day-to-day supervision. (Exeter theoretical physics group)

Adam Monier is a marine microbiologist whose profile focuses on ecology and evolution of microbial eukaryotes and their associated viruses in oceans. This can help connect model parameters and ecological interpretation to marine settings, though much of his visible work concerns phytoplankton viruses rather than bacterial phages. Kit Yates at Bath contributes expertise in stochastic simulation and hybrid models. The research portal confirms his academic base is Bath. Ask whether Bath visits are expected, what Kit Yates's formal supervisory role will be, and how often he will meet the student. (Monier profile, Yates profile)

Recent Important Publications

• Bisesi et al., 2024, mSystems — “Bacteriophage specificity is impacted by interactions between bacteria.” Coauthored by Moebius, this study combines a microbial community system with mathematical modeling and shows that interactions between prey bacteria can affect whether phages behave as generalists or specialists. It supports testing the surrounding community context; it does not examine flow-driven isolation or ocean-scale simulations. (PubMed record)
• Cameron, Smith and Yates, 2025, Mathematics — “The Spatial Regime Conversion Method.” This paper is the closest methodological precedent: an adaptive hybrid of discrete stochastic and continuum reaction–diffusion representations. Its tests are one-dimensional diffusion and pattern/travelling-wave examples rather than host–virus coevolution. (Bath research record)
• Meyer et al., 2024, The ISME Journal — “Temperature modulates dominance of a superinfecting Arctic virus in its unicellular algal host.” Monier is a coauthor. The study shows that temperature changed competitive outcomes between viruses in an Arctic algal host, underscoring environmental sensitivity in marine viral systems. It does not test bacterial phages, fluid flow or coevolutionary memory. (PubMed record)

Lab, Resources, and Collaboration Environment

The LSI combines mathematical and physical sciences with experimental biological research and lists phage, virus and microbe research spanning transcriptomics, genome editing and microfluidics. Exeter Physics describes Linux computing and a Beowulf cluster previously used for some astrophysical and geophysical fluid-flow modeling. These sources support a relevant interdisciplinary and computational environment. Ask which HPC allocation, software stack and GPU access will be available, what parameter data can be used, and whether an experimental group will contribute. (LSI microbe research, Physics facilities and training)

Funding, Application, and Living Cost

The September 2027 EPSRC DLA call offers up to 16 awards across participating projects; it is a competitive scheme, not a guaranteed project award. The award page lists an indexed stipend for up to 3.5 years, the current 2026/27 rate of £21,805 per year, Home tuition fees and a £5,000 Research Training Support Grant over 3.5 years. The difference between Home and International tuition is covered by the University for successful international candidates, and the general 2027/28 guidance limits international-fee-status awardees to up to 30% of the cohort. Visa, healthcare surcharge and moving costs are excluded. Ask the award team to confirm the final 2027/28 stipend. (Award funding details, EPSRC DLA 2027 guidance, UKRI stipend table)

The stated application deadline is midday on Tuesday 8 December 2026. Applicants may apply to up to three projects, submitting a separate application for each and stating a preferred choice if applying to more than one. The general criteria are a First or Upper Second in an appropriate science, engineering or technology area, with Lower Second applicants considered if they also have a Master's degree or significant relevant non-academic experience. The project PDF says there are no additional project-specific entry requirements. Required application materials include a personal statement naming the project, CV, transcripts, two references and English-language evidence when applicable; all documents must be in English, and degree certificates require certified translations. (Exeter DLA application page, DLA eligibility and application information, official project PDF)

The reference deadline needs written clarification: Exeter’s project award page says 8 January 2027, while its general DLA information page says 15 February 2027. Both pages agree on the 8 December application deadline. The project award page also lists likely interviews for 15–24 February 2027; the general DLA page's overview gives the same 2027 window, but its application subsection retains 2026 interview and outcome text. Confirm the official schedule, and use the project page's 8 January date as the safe reference plan until PGR Admissions replies. (Project award page, general DLA information page)

Exeter estimates basic student living costs at £1,300–£2,000 per month, based on local spending in April 2026. The current stipend benchmark averages about £1,817 per month before any future rate change. Compared with the published cost range, that suggests an illustrative monthly headroom of around £517 at the low end, or a £183 shortfall at the high end. It is not a 2027/28 budget forecast. The university's 2026/27 accommodation examples vary substantially: self-catered halls are listed at £150–£270 per week, while private rooms are £135–£250 before bills. The current postgraduate accommodation guarantee applies only to eligible international-fee-paying postgraduates who meet its conditions; Home-fee PGR accommodation is not guaranteed for 2026/27. Rates and rules for a 2027 start should be checked again. (Exeter budgeting guidance, Exeter Room Finder, postgraduate accommodation rules)

Applicant Fit and Preparation

Required Background and Skills

Officially, the project adds no project-specific entry requirements. General EPSRC DLA eligibility expects a relevant science, engineering or technology degree at First or Upper Second level, or a Lower Second alongside a Master's degree or significant relevant experience. English proficiency evidence is required when applicable. The project is computational and model-led; a strong quantitative background is therefore highly relevant to the work, but the project PDF does not state a formal mathematics grade or prior-programming threshold.

Preferred Experience and Suggested Preparation

The advertised tasks imply that experience with mathematical modeling, stochastic or agent-based simulations, scientific programming, numerical analysis and machine learning would help an applicant engage quickly. Those are suggested preparation based on the work, not stated admissions prerequisites. A useful application would make concrete the applicant's experience with one or more of: implementing and validating simulations, translating ecological assumptions into equations or algorithms, analyzing noisy data, and explaining model limitations to collaborators in another discipline. The research proposal and interview can distinguish these competencies without claiming that any one programming language or software package is required.

The transferable skill set could map to academic computational biology or mathematical biology, scientific software and modeling, environmental or ocean systems analysis, and data-intensive research roles. This is an inference from the project methods and Exeter Physics destination examples, not a placement promise. Skills England projects growth in UK life-sciences priority occupations and highlights digital literacy, numeracy and scientific/data analysis, but the forecast is sector-wide, uncertain and not specific to a microbial-ecology PhD. (Exeter Physics career information, Skills England life-sciences assessment)

Next Actions and Questions to Verify

Before Applying

1. Ask PGR Admissions to confirm whether referees must submit letters by 8 January or 15 February 2027, and get the response in writing.
2. Confirm the exact 2027 registration/start date, application route and time zone for the midday 8 December 2026 deadline.
3. If applying for international-fee-status funding, confirm eligibility under the EPSRC residency rules and how the 30% cohort limit is applied.
4. Confirm that 2027/28 funding covers the full expected registration period and ask when the indexed stipend rate will be set.

At Interview

1. Which microbe–virus system and evolutionary mechanisms will anchor the models? What parameters will be estimated from published data or measured experimentally?
2. Which flow fields, spatial scales and oceanic conditions will be tested, and how will a more complex simulation be validated against the simpler model?
3. What is the proposed hybridization rule between agent-based and concentration-based representations, and what measurable benchmark will demonstrate its efficiency and accuracy?
4. What are the respective responsibilities of Moebius, Kattnig and Monier, and how will Bath collaborator Kit Yates contribute? How often will each supervisor meet with the student?
5. Is any experimental collaboration planned to validate the model, or is the PhD intended to remain computational? What HPC/GPU access and project-specific computing allocation are available?

Before Accepting an Offer

1. What is the confirmed stipend for 2027/28, the award's payment schedule and the exact tuition/fee status in the written offer?
2. How does the up-to-3.5-year award align with the University's maximum four-year full-time PhD registration period, and what support is available if submission falls after funding ends?
3. For an international award holder, which visa, healthcare surcharge, relocation or other costs remain uncovered, and is the stated Exeter fee waiver confirmed for the full expected study period?
4. What is the confirmed accommodation cost range and eligibility for 2027/28, including whether utility bills are included?

Evidence and Sources

Project and Programme

• EPSRC DLA award, Ref 6022
• Official project description PDF
• EPSRC DLA application page
• EPSRC DLA eligibility and application information
• Physics PhD and Research Degrees
• Exeter research degree durations
• LSI PhD Programme in Complex Living Systems
• Living Systems Institute overview
• Exeter Phages, Viruses and Microbes research area

School, Group and Supervisory Team

• Moebius Group
• Adam Monier profile
• Exeter Theoretical Physics research centre
• Kit Yates research profile
• Exeter REF 2021 results
• Exeter rankings table

Publications and Field Evidence

• Bacteriophage specificity and bacterial interactions, 2024
• Bacterial resistance and viral coexistence, 2024
• The Spatial Regime Conversion Method, 2025
• Arctic virus competition and temperature, 2024
• Stable phage infection transport with migrating hosts, 2026
• Spatiotemporal bacterial–phage coevolution, 2022
• Marine Aeromonas–phage coevolution, 2023

Funding, Living Cost and Careers

• UKRI stipend and fee levels
• Exeter living-cost budgeting guidance
• Exeter Room Finder
• Postgraduate accommodation rules and guarantee
• Skills England Life Sciences assessment