I graduated from the University of Birmingham with a First Class MSci Mathematics degree in July 2021. During my time at Birmingham, I developed a keen interest in mathematical biology and in particular, topics with interdisciplinary or real-world applications. My main research focus during my undergraduate studies was modelling and investigating the collective motion of birds, but I have also spent time exploring the field of human opinion dynamics.
I started my Integrated PhD in Statistical Applied Mathematics as a member of SAMBa Cohort 8 at the University of Bath in September 2021, obtaining an MRes qualification during my first year of study. I am currently in my final year of PhD study, on the topic of modelling the collective behaviour of Trinidadian Guppies.
My PhD project is titled "Collective behaviour under non-reciprocal pairwise interactions", supervised by Dr. Richard James and Prof. Tim Rogers. Preliminary experimental work and mathematical modelling suggest that sexual conflict can give rise to non-reciprocal interactions and anomalously fast diffusion of pairs of Trinidadian Guppies (Poecilia reticulata). In the long-term, their behaviour also results in key ecological and evolutionary processes such as population dispersal and invasion of alien species. To combine the biology of pairwise interactions through to population level consequences will require mathematical models of processes at different time, spatial and social scales. In biological terms, such problems lie at the intersection of movement ecology and collective behaviour. Using mathematical techniques from agent-based modelling, mean-field and coarse-grained approximations and continuous time PDE modelling, the aim of the project is to develop a general framework, or suite of mathematical models, to interpolate between and extrapolate from one social, spatial and temporal scale to the next, modelling the effect on non-reciprocal social forces in Trinidadian Guppies on large-scale population structure and the ecological and evolutionary consequences of their behaviour.
As part of my PhD project, I have also had the privilege of spending two weeks working at the University of Exeter with my external supervisors Dr. Safi Darden and Prof. Darren Croft, designing and carrying out experiments with Trinidadian Guppy Fish. The experiments aimed to investigate the role of sexual conflict in animal movement, and how significant a factor it is in driving it. Guppies were housed in tanks at different sex ratios and monitored for 24 hour periods. Within each tank, there was a waterfall leading to a separate area of the tank, requiring the guppies to make an active decision to leave their existing environment, we could then gain insight into which sex was more likely to jump at different ratios. Analysis of the data is ongoing, but the results from the experiments will eventually inform the mathematical modelling I develop, meaning it will be grounded in real-word observations and behaviours.
During my undergraduate degree, I had the opportunity to complete two research internships. The first of which, funded by EPSRC, was an in depth study of the Cucker-Smale and Cucker-Dong models of collective animal motion. I subsequently completed both my third year and Master's projects on the topic, both of which were supervised by Dr. Galane J. Luo. In the latter, I devised a new, agent-based model of collective motion, specifically designed to recreate the murmuration phenomena commonly observed in large flocks of starlings. The model was simulated numerically for a wide range of parameter values and the rich behaviours resulting from these simulations were investigated in detail. I was also part of a British Academy funded project which set out to develop a novel, agent-based model of human opinion dynamics. Agents in the model update their opinions based on interactions with others, providing the pair exceeds a certain "affinity threshold". The concept of memory was also introduced, creating a non-Markovian process of opinion updating. The model successfully recreates many socio-psychological phenomena, such as extremism, segregation and oscillatory opinions, more details can be found in our publication in the Journal of Mathematical Sociology.
Stokes, B.M., Rogers, T. and James, R., 2024. Speed and shape of population fronts with density-dependent diffusion. arXiv preprint arXiv:2407.07915.
Stokes, B.M., Jackson, S.E., Garnett, P. and Luo, J., 2022. Extremism, segregation and oscillatory states emerge through collective opinion dynamics in a novel agent-based model. The Journal of Mathematical Sociology, pp.1-39.
Mathematical Models in Ecology and Evolution and European Conference on Mathematical and Theoretical Biology - July 2024: "Speed and shape of population fronts with density-dependent diffusion" (Talk)
INI Mathematics of Movement Workshop - 17th - 21st July: "The Role of Density Dependent Diffusion in Reaction-Diffusion Systems" (Poster)
Soapbox Science Exeter - 10th June 2023: "Why birds only need to know how to count to 7!" (Talk)
British Applied Mathematics Colloquium - 4th April 2023: "Extremism, segregation and oscillatory states emerge in a novel agent-based model" (Talk)
Behind the Research is an initiative developed and run by PhD students in the Department of Mathematical Sciences at the University of Bath. The aim of the initiative is to demystify the world of academia, showcasing the daily lives, the highs and lows of a research student, and the real people “Behind the Research”.
We regularly live stream on Twitch, hosting guests from all walks of academic life, showcasing their honest, unfiltered experiences, as well as our own. You can find out more on our website!
The Piscopia Initiative is a UK-wide network of women and non-binary undergraduate students, PhD students, and researchers in Mathematics and related disciplines, with the aim of encouraging women and non-binary people to pursue a PhD in Mathematics. We also want to support and celebrate current postgraduate students and researchers at all career stages.
Piscopia have local committees at Universities across the UK and I lead the committee at the University of Bath. You can find out more about Piscopia and their nationwide activities on their website.