Brennen Fagan

Postdoctoral Research Associate,
Leverhulme Centre for Anthropocene Biodiversity

Mathematics of Biodiversity Change

brennen.fagan@york.ac.uk

Biography

I am a Postdoctoral Research Associate with LCAB and the Department of Mathematics studying the Mathematics of Biodiversity Change.

I received my undergraduate degree at California State University, Fresno with the Smittcamp Family Honors College and my PhD in Mathematics from the University of York on a departmental teaching studentship. My PhD studied historical war data with the York Historical Warfare Analysis Group to better understand human conflict.

LCAB provides grounds for interdisciplinary collaboration: I work with colleagues from Archaeology, Biology, and History regularly, and have been exploring topics with colleagues from Environment & Geography and English. This diversity of backgrounds allows for more holistic approaches to tackling some of the central problems of our time.

Research

At LCAB, I juggle dual roles relating to my interests in computational mathematics and statistical and mathematical modelling. My main project at LCAB uses a mathematical model of an ecosystem to investigate questions about how dispersal, land use change, and our ability to observe our environment change biodiversity and reports thereof. In particular, do two studies studying the same thing in different ways get the same results?

Outside my main project, I have collaborated on projects including modelling the evolution of maternal transmission and modelling the diversity of pollen grains over the Holocene. I’m also interested in exploring topics around decision making and past and fictional ecologies. I also am generally interested in the applications of statistical and computational methods, and so have been involved in various modelling, statistics and computing help groups in LCAB.

In parallel to my roles in LCAB, my research also touches on historical decision-making and modelling historical and socio/physical processes.

My collaborators and I are currently advertising for 3 PhD projects set to begin in September 2025. The three projects are each applied and involve modelling aquatic ecology, modelling connectivity, and modelling tree cover and carbon stocks respectively.

Publication highlights

Fagan, B., Pitchford, J. W., Stepney, S., & Thomas, C. D. (2023). Increased dispersal explains increasing local diversity with global biodiversity declines. Global Change Biology, 2023.06.09.544194. 

Fagan, B. T., Constable, G. W. A., & Law, R. (2024). Maternal transmission as a microbial symbiont sieve, and the absence of lactation in male mammals. Nature Communications, 15(1), 5341. 

Fagan, B., Horwood, I., MacKay, N., Price, C., & Wood, A. J. (2023). Quantifying Counterfactual Military History. CRC Press.

Funder

• The Leverhulme Trust