Much of past human history can be written without too much reference to the effects of the physical environment, much less the results of our own impacts on it. But human numbers and their increasing impacts have now grown to the point where their scale rivals the planet’s natural biogeochemical processes which created the biosphere and which struggle to maintain it. The talk will document this statement, and suggest some implications for, as it were, the post-Metternich age of relations among nations.

Lord May of Oxford, OM AC Kt, is former President of the Royal Society (2000-2005), and holds a Professorship jointly in the Department of Zoology, Oxford University, and at Imperial College London. For the five-year period ending September 2000, he was Chief Scientific Adviser to the UK Government, and Head of its Office of Science and Technology. Lord May studied theoretical physics, but for the last 25 years he has applied mathematics to the study of the way population structure affects ecology, especially in the context of infectious diseases. His research interests centre on the causes, consequences, and magnitude of biological diversity; mathematical models of the population dynamics of the immune system; transmission of, and defences against, viral infections and other disturbances in complex networks, including ecological food webs, infectious diseases, and IT systems.