<a id="top" name="top"></a>Research Projects
The research on ageing is progressing along two main paths: fundamental research is seeking to discover the general genetic framework for the evolution of ageing; applied research is seeking medical interventions that can postpone or slow down ageing and ameliorate the effects of age-related diseases. Recent advances on both of these frontiers suggest that we may have to reconsider some of the core theoretical foundations of the evolutionary theory of ageing. By combining novel theory, experimental evolution, data sets from long-term field studies, quantitative genetics and the latest developments in genomics, we aim to provide a deeper understanding of why and how ageing evolves. We also have a special interest in understanding the phenomenon of sex differences in senescence, which are ubiquitous across the animal kingdom and represent a long-standing challenge in biology. Males and females differ not only in how long they live and when do they start to senesce, but also in how they react to environmental interventions aimed at prolonging their life span or postponing the onset of ageing. Sex differences in lifespan and ageing have therefore important implications beyond the questions posed by fundamental science. Our research on ageing is currently funded by the European Research Council (ERC), the Swedish Foundation for Strategic Research (SSF), the Swedish Research Council (VR), the Wenner-Gren Foundation and Carl Trygger’s Foundation.
<a id="proj1" name="proj1"></a>Why and how ageing evolves?
Senescence evolves because the strength of natural selection declines with age. A classic prediction based on this logic is that an increase in extrinsic mortality leads to evolution of rapid senescence. However, this prediction can be modified, and even reversed, if mortality is condition-dependent. Since mortality in nature is likely to be condition-dependent, resolving this problem is key to our understanding of how ageing evolves. We are testing these fundamental questions using an experimental approach.
<a id="proj2" name="proj2"></a>Sex differences in lifespan and ageing
Sex differences in lifespan and ageing are ubiquitous across the animal kingdom and represent a long-standing challenge in evolutionary biology. We are interested in understanding how differences in life-history strategies and associated mortality rates generate sex-specific senescence and whether intra-locus sexual conflict prevents the sexes from reaching their sex-specific optima in resource allocation between somatic maintenance and reproductive effort. Last but not least, we are keen to investigate the role of condition-dependent selection in generating sex differences in ageing.
<a id="proj3" name="proj3"></a>Evolutionary consequences of lifespan extension
Several environmental manipulations (e.g. dietary restriction) are known to extend reproductive lifespan. However, what are the long-term consequences of evolving under such conditions? Different theoretical conjectures predict different evolutionary scenarios. We are testing this directly by subjecting populations of fruit flies to evolve under a variety of nutritional conditions with known effects on lifespan and reproduction.
People currently involved: Felix Zajitschek, Tuo Jin, Cindy Canton, Urban Friberg, Alexei Maklakov
<a id="proj4" name="proj4"></a>Sex-specific genetic variation in ageing
In this project we are characterizing within population genetic variation in ageing and lifespan, with a special emphasis on sex differences. We are also looking into how this variation is distributed over the genome and how selection is acting on it.
People currently involved: Urban Friberg
<a id="proj5" name="proj5"></a>Somatic mutations and ageing
Despite large efforts, our understanding of the direct mechanisms that cause ageing are still not well understood. One hypothesis suggests that increased probability of death with age is caused by continuous accumulation of somatic mutations. In this project we are testing this hypothesis by investigating if within-population variation in lifespan is associated with the pace by which genotypes accumulate somatic mutations.
People currently involved: Rebecca Dean, Alexei Maklakov, Urban Friberg