Scheme: University Research Fellowship
Organisation: University of Sheffield
Dates: Sep 2008-Jun 2013
Summary: I work on a novel field at the interface between evolutionary biology, medical epidemiology, history, demography and anthropology to achieve a comprehensive assessment of the ecological and demographic factors influencing senescence rate and lifespan in humans. Ageing, senescence and death are universal processes of virtually all living things, and fundamental concepts which preoccupy the mind of every human at some stage. In evolutionary terms, all organisms should seek to maximise the number of grandchildren they produce, a goal that is normally achieved by breeding throughout life. Humans are exceptional: women are virtually unique among animals in experiencing menopause and a prolonged postreproductive lifespan and why male lifespan is comparable to their sterile partner is perplexing. One explanation is that both increase their numbers of grandchildren by directing their resources to offspring already produced, rather than by producing more. Whether or not this is the case is unknown, but my research shows that women have the potential to increase grandchildren numbers by helping their adult offspring to reproduce (Nature 2004). This has fascinating implications: All animals (humans included) have finite resources which must be split between reproduction and self-maintenance. Theory suggests that evolutionary success is maximised by optimising the inevitable trade-off between investments in current versus future offspring. Humans might not only have to optimise this trade-off, but consider the trade-off between investment in parenting and grandparenting. How humans achieve this and how the trade-off is modified by ecological, social and demographic circumstances is rarely considered, but is essential to understanding the ecological and genetic basis of reproductive effort, senescence and lifespan in humans and animals in general.
Dates: Sep 2003-Aug 2008
Summary: This project summary is not available for publication.