Biosciences Seminar Series - Spring 2014
08 May 2014 - 1pm - Zoology Museum (Wallace 129)
Exploring the landscape of ageing and lifespan in the tree of life
|Photograph: Rodrigo Buendia/AFP/Getty Images|
Why do we age? Yes, we get older, but why does our mortality risk increase? Why does our fertility decrease with age? For example, at least some cells seem to be able to continue growing and dividing without a decline in performance (e.g. see here about the 'immortal' HeLa cells, the cells of Henrietta Lacks). One well-known idea is that aging is simple an inevitable outcome of evolution, as the famous evolutionary biologist W. D. Hamilton argued (see here). However, as our seminar speaker of this week, Dr. Owen Jones, has shown in a recent paper (see here and here), things look different once one starts to compare patterns of aging across species with contrasting lifespan and demographics, which strikingly had never been done before!
Owen is an evolutionary biologist and associate professor at the University of Southern Denmark, broadly interested in demographics and in using quantitative and comparative methods. After working on the famous Soay sheep project for his PhD at Imperial College London and the Macaulay Institute at Aberdeen, Owen worked for his first postdoc on the LITS project at Imperial College London, setting up a database of UK-based long-term individual-based time series data sets. Owen moved then to the Zoological Society of London to work on population genetics, after which he moved to the Max Planck Institute for Demographic Research in Rostock, Germany, where he stayed until joining the University of Southern Denmark last year.
During the seminar, Owen will present his latest work on the aging patterns across a wide range of organisms, ranging from humans the the hydra to long-lived trees.
Some species live for a very long time, others more fleeting. Animals like elephants, whales and tortoises are comparatively long lived and in the plant kingdom bristlecone pines have life spans of around 5,000 years. At the other end of the scale, creatures such as the mayfly or annual plants live for just a day or a year. Underlying these life span estimates are the demographic trajectories of mortality and fertility that respectively capture the changing probability of death and number of offspring produced, with age.
|Photo: Neil Miller|
The evolutionary theories of ageing suggest that senescence, a decline in fertility or an increase in mortality risk with age, is inevitable. Is it really? I will explore demographic data from the animal and plant kingdoms to question the inevitability of senescence and to highlight the need to examine a broad taxonomic range in order to understand the evolution of demographic traits.
Everyone is welcome to attend!