Navigation Links
Genetic study shows major impact of climate change on Antarctic fur seals
Date:7/23/2014

Genetic analysis of Antarctic fur seals, alongside decades of in-depth monitoring, has provided unique insights into the effect of climate change on a population of top-predators. Published in Nature this week, the findings show that the seals have significantly altered in accordance with changes in food availability that are associated with climate conditions. Despite a shift in the population towards 'fitter' individuals, this fitness is not passing down through generations, leaving the population in decline.

Environmental change is expected to affect many species and biological systems throughout the world. To understand these changes long-term monitoring is required. The British Antarctic Survey's unique Long Term Monitoring and Survey programme has given researchers a rare opportunity to explore how fur seal life histories have changed over time in relation to the climate and food availability.

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.

Lead author, Dr Jaume Forcada from the British Antarctic Survey explains:

"Compared with 20 years ago, we can see that female fur seals are now born with a lower weight, those that survive and return to breed tend to be the bigger ones and they have their first pup later in life than they used to. Such changes are typically associated with food stress.

"An important food source for the seals is Antarctic krill. Decades of data collected at South Georgia show how changes in the seal population have occurred over time with changes in krill availability. Even if krill is very abundant, environmental variation determines its availability in the seals' feeding grounds. This environmental variation is driven by the climate which impacts local atmospheric, sea ice and oceanographic conditions. Adverse climatic conditions are typically associated with low krill availability, and reduce the survival and breeding success of fur seals."

The researchers found that females who did survive to motherhood were likely to be more 'heterozygous'. This is where an individual possesses a higher level of genetic variation and is associated with higher fitness in many species. Whilst these females are more likely to survive and breed, their pups will only have the same advantage if they too are heterozygous. However, the heterozygous characteristic is not inherited; it depends on which male the female mates with and so arises mostly through chance. This means that many seals are born who are not heterozygous and are therefore less able to cope with the changing environment.

Co-author, Dr Joe Hoffman from Bielefeld University 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."

Climate change is already altering environmental pressures on many species, and scientists do not yet know how populations will cope with these new environments. This study shows that natural selection on a fur seal population has altered as a result of climate change and that the seals have been unable to evolve in response.

Impacts on one species can affect a whole ecosystem. The world continues to change and, if we are to adapt, it is essential to anticipate future changes in natural systems. Long-term data sets are a valuable resource for biologists who must forecast how species will respond to future environmental change.


'/>"/>
Contact: Paul Seagrove
psea@bas.ac.uk
44-012-232-21414
British Antarctic Survey
Source:Eurekalert

Related biology news :

1. Nearby chimpanzee populations show much greater genetic diversity than distant human populations
2. Will a genetic mutation cause trouble? Ask Spliceman
3. UC Santa Barbara researchers discover genetic link between visual pathways of hydras and humans
4. Perception and preference may have genetic link to obesity
5. A foot in the door to genetic information
6. Genetic survey of endangered Antarctic blue whales shows surprising diversity
7. Epigenetic signatures direct the repair potential of reprogrammed cells
8. Epigenetics and epidemiology -- hip, hype and science
9. Genetic variation in East Asians found to explain resistance to cancer drugs
10. First complete full genetic map of promising energy crop
11. Genetic research develops tools for studying diseases, improving regenerative treatment
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/21/2017)... 2017 Der weltweite Biobanking-Sektor wird ... einem Gespräch mit mehr als 50 Vertretern aus verschiedenen Branchen ... gilt, um diese Prognose zu realisieren. ... Zu den ... finanziellen Mittel für die Biobank, die Implementierung Zeit sparender ...
(Date:2/14/2017)...  Wake Forest Baptist Medical Center today announced Julie Ann ... officer (CEO). Freischlag joins the medical center on May ... M.D., who last year announced that he would transition ... leading it since 2008.   As CEO, ... Baptist,s academic health system, which includes Wake Forest School ...
(Date:2/13/2017)... -- Former 9/11 Commission border counsel and Special Counsel ... of Identity Strategy Partners, LLP, today releases the ... Order: Protecting the Nation From Foreign Terrorist Entry Into ... President Trump,s ,Travel Ban, Executive Order gains more notoriety ... travel ban, it is important that our national discourse ...
Breaking Biology News(10 mins):
(Date:2/24/2017)... -- China Biologic Products, Inc. (NASDAQ: CBPO) ("China Biologic" or ... China, today announced its financial results for the fourth quarter ... 2016 Financial Highlights Total sales in ... terms, or increased by 13.6% in USD terms to $77.6 ... Gross profit increased by 13.3% to $46.8 ...
(Date:2/23/2017)... , ... February 23, 2017 , ... ... Discovery Services portfolio to include an array of biochemical analyses critical for ... data to drive their hit-to-lead and SAR programs, including inhibitor potency and selectivity, ...
(Date:2/23/2017)...  Imanis Life Sciences announced today the launch ... viruses for virotherapy research. These viruses are licensed ... vaccinia virus-based technology platform for research use. ... partnership with Genelux to offer researchers, for the ... in research," said Dr. Kah Whye Peng ...
(Date:2/23/2017)... ... ... The Greater Gift Initiative, Inc , (GGI) a Winston-Salem, NC 501(c)3 non-profit, ... is to advance global health and highlight the greater good of clinical trial participation ... trial volunteer. The vision of GGI is to serve as a philanthropic connector between ...
Breaking Biology Technology: