The John C. Marsden Medal

£1,000 and a medal awarded for the best doctoral thesis in biology.

Dr John C. Marsden was the Executive Secretary of the Society from 1989 to 2004 and was elected as a Fellow honoris causa in 2005 in recognition of his services to the Society. The medal is awarded annually in Dr John C. Marsden's memory for the best doctoral thesis in biology. It is open to any candidate whose research has been carried out whilst registered at any UK institution. Theses on the full range of biology are eligible. Nominations are received from the Head of Department or the supervisor of the candidate.

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Eligibility Criteria:

  • Open to PhD candidates whose doctorate has been awarded during the previous 18 months (from closing date of nomination).
  • PhD candidate can be any nationality, but research to have been carried out whilst registered at a UK institution
  • The thesis must be of outstanding quality and be on any aspect of biology
  • Nominations to be made by the Head of Department or supervisor of the candidate
  • Up to two candidates may be nominated per department
  • Nominee cannot, at the time of nomination, be a member of Council
  • Nominee does not need to be a Fellow of the Society
  • We do not accept self-nominations

Evaluation criteria will include (scores in parentheses):

  1. Writing and organisation (0-10)
  2. Presentation (format, illustrations) (0-10)
  3. Intrinsic interest of question (0-20)
  4. Contextualization of problem (0-10)
  5. Quantity of data collected (0-10)
  6. Quality of data collected (0-10)
  7. Data analysis (0-20)
  8. Discussion depth and breadth (0-10)
  9. Published papers (0-10)
Tomos Potter
Photo credit: Analise Fussell

Dr Tomos Potter, Florida State University, John C. Marsden Medal 2023

Dr Tomos Potter’s PhD involved complex statistical analyses of observational data, and theoretical modelling. Studying the freshwater stream ecosystem of Northern Trinidad, his focus was on guppies. This work revealed how eco-evolutionary feedback could result in environmental impacts on phenotypic trait expression and cryptic evolution, and involved the analysis of one of the largest pedigrees ever constructed for a free-living population of fish; it is destined to become a classic.

Dr Timothy AC Lamont

Dr Timothy AC Lamont, University of Exeter, John C. Marsden Medal 2022

Thesis titled 'The changing sound of the sea: soundscapes as indicators and drivers of ecosystem transition on tropical coral reefs'

Timothy Lamont’s doctoral thesis took an unexpected turn after a catastrophic coral bleaching event devastated his field site. He turned this to advantage, developing innovative ways of documenting the change in the soundscape after biodiversity loss, and conducted two ambitious field experiments to assess impacts of changes in the acoustic landscape on future recruitment of coral reef fish. His results showed the importance of sounds, even underwater, to the eventual recovery of natural reef ecosystems. He turned his gained knowledge towards finding solutions, leading to the exciting potential of “acoustic enrichment” to restore fish communities on degraded coral reefs. This method, with its association acoustic toolkit, is now being trialled at restoration programmes around the world. His exceptional PhD journey has established him as a global voice for marine conservation and habitat restoration.

Benjamin Van Doren

Dr Benjamin Van Doren, University of Oxford, John C. Marsden Medal 2021

Thesis titled 'Flexibility in an avian migration across scales'

Migratory birds form a network of organisms that connect the world, serving as indicators of ecosystem health and biodiversity on a hemispheric scale, but they are threatened by the rapidly increasing pressures of global change. Understanding the capabilities of migratory birds to respond to established and emerging challenges requires knowledge of the complex interactions among individuals, populations, species, and natural and built environments. Benjamin van Doren’s thesis surveys the drivers of bird migration across scales. Using both a wide variety of data from different sources, he focussed on the contributions of the innate migratory program, birds’ responses to environmental cues and conditions, and the influence of human activity on migratory behaviour. He showed how natural selection can act on birds’ migratory strategies and that ongoing responses to climate change in long-distance migrants involve not only phenotypic plasticity, but also evolutionary change.

Benjamin also developed methods to reliably predict nightly avian migratory movements; the resulting “migration forecasts” have generated wide interest among scientists, conservationists, aviators, and the public. Finally, he showed that artificial light at night can drastically affect migratory journeys and that human activity can impact not only the in-flight behaviours of migrating birds, but also their broader ecology. The thesis shows that flexibility observed in migratory birds stems from a range of sources, innate and external, and that variation in migratory phenotypes may be key to responding to environmental change. Several chapters have already been published in high impact journals, and methods for prediction will have wide-ranging application.

Patrick Kennedy

Dr Patrick Kennedy, University of Bristol, John C. Marsden Medal 2020

Thesis titled 'Uncertainty and the evolution of altruism: Theory and fieldwork in the paper wasps of Central and South America'

Patrick's thesis considers two major topics of broad biological relevance: how unpredictability in environmental conditions can impact the evolution of altruism (costly helping of others), and why some individuals in social wasp populations drift between nests (helping other colonies). He tackled the first using complex analytical modelling and evolutionary simulations, while the second involved arduous fieldwork, experimental manipulations and sophisticated statistics. Patrick's work shows exceptional width of approaches and expertise. All hypotheses are introduced lucidly with wide-ranging referencing of not just biological literature but also economic, biochemistry and medicine. In fact, there is enough material for not one but two theses.

The thesis includes several original ideas. He drove a theoretical reworking of Hamilton’s rule; possibly the most-famous, widely applicable and influential equation in behavioural ecology, since it relates to inclusive fitness and altruism. The paper is already generating considerable follow-up theoretical attention and empirical testing in various taxa. Another submission to Nature is imminent, combining analytical modelling of three proposed hypotheses for drifting behaviour, Markov-chain modelling of ¼ million field data points to test the most plausible (the non-linear returns hypothesis), and evolutionary simulations to assess the likely selection pressures. At least six more primary research and review/opinion papers are planned from the thesis. Patrick has been active in outreach to schools internationally, as well as an invited speaker at meetings in UK, Portugal, Switzerland, Brazil and Panama.

Dr Sarah Hill, Medal winner 2019
Dr Sarah Hill, Medal winner 2019