Dr Joe Hoffman, from Bielefeld University and a scientist working on the CACHE-ITN project, is co-author of a paper published in Nature this week in which he looks at the genetic analysis of Antarctic fur seals, alongside decades of in-depth monitoring, to provide unique insights into the effect of climate change on a population of top-predators.
Researchers from the British Antarctic Survey and Bielefeld University in Germany analysed data gathered from as far back as 1981 to assess changes over generations of female fur seals on South Georgia, in the South Atlantic Ocean.
Dr Joe Hoffman from explains: “We found that, over the last two decades, the proportion of breeding females that are highly heterozygous has increased, as these individuals are more likely to survive the changing conditions. Strong selection by the environment can drive rapid evolution. However, in this case the seals do not appear to be evolving because surviving females do not pass their high heterozygosity on to their offspring.
“Therefore, with each new generation, the process of selection has to start all over again, with only those individuals that happen to be born more heterozygous having a good chance of survival. As the climate continues to change, many fur seal pups are not surviving to adulthood and the population is declining.”
Joe is a co-supervisor with CACHE, looking at ‘Quantification of natural variation in shell thickness and production across a latitudinal gradient and relation to environmental parameters and the underlying population genetics’ and is also on the CACHE Supervisory Board.
The paper Climate change selects for heterozygosity in a declining fur seal population by Jaume Forcada and Joseph Ivan Hoffman can be viewed here: http://dx.doi.org/10.1038/nature13542