Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Telomere length as an indicator of life expectancy for the southern giant petrel

18.01.2011
The length of telomeres, the DNA fragments that protect the ends of chromosomes from deterioration, could be an indicator of life expectancy in the southern giant petrel (Macronectes giganteus), an emblematic species of the Antarctic and sub-Antarctic regions, according to an article published in the journal Behavioral Ecology by an international group of researchers including Dr. Jacob González-Solís, from the UB’s Department of Animal Biology and the Institute of Research of the Biodiversity (IRBio) at the University of Barcelona.

The project on which the article is based, which is directed by the expert Pat Monhagan (University of Glasgow, UK), also reveals that adult male giant petrels have shorter telomere lengths than females, a genetic difference that had not been documented until now in a scientific study of a bird species.

Telomeres, situated at the terminal end of chromosomes, are key elements in cell division. According to international research studies, telomeres shorten progressively with each cell division, and this reduction in length is associated with cell aging. The 2009 Nobel Prize for Medicine, awarded to Elizabeth H. Blackburn, Carol W. Greider and Jack Szostak, reflects the importance of the biological role of telomeres in cellular and molecular machinery.

The article in Behavioral Ecology focuses on a study of the giant petrel, a large scavenger found in the Arctic and sub-Antarctic regions which displays significant differences between males and females (size, behaviour, diet, etc), carried out in a breeding colony on Bird Island in South Georgia. “The giant petrel is a bird that can live over 50 years, making it ideal for studies of longevity”, says Dr. González-Solís, who nevertheless explains that, “It is not easy to study the effects of longevity in wild species. You need to be able to work with communities that have been extensively observed since the mid-part of the 20th century, which is the case of the colony on Bird Island, where we have been able to monitor petrels in different age groups”.

Why telomere length is different?

Male telomere length is known to be shorter in humans and in other animal species such as rats. The article in Behavioral Ecology looks at the genetic material of red blood cell samples taken from giant petrels and is the first research study to reveal differences in telomere length between males and females of the same bird species, raising the question of why telomere shortening is more pronounced in males than females. There appears to be no single explanation, although for González-Solís the different lifestyles of males and females may be one, if not the only, explanation: “There is a clear division of roles between males and females, particularly as regards feeding: males compete for the prey of seals and penguins on Antarctic beaches, whereas females feed on marine species including fish, squid or krill”. When animals have to compete for food, size is an advantage, and González-Solís explains that, “the specialized feeding strategies of males have led to an increase in body size, which raises the cell division rate and creates greater oxidative stress, hence the telomere shortening observed”. As he explains, “this is not consistent with observations in other dimorphic species such as the wandering albatross or the European shag, in which telomere length is similar between sexes”.

The difference in telomere length between males and females is also found in chicks, a finding that cannot be accounted for by lifestyle differences, since, as González-Solís explains, “At this stage the birds have not begun to display different behavioural patterns, so the different roles of males and females cannot be the only reason for the disparity in telomere lengths. In the case of chicks, perhaps it is simply that sexual dimorphism imposes different growth rates, which may promote greater telomere shortening in males. At the moment there are a number of theories and more research will be needed to work through them”.

Telomere length and bird survival

Another interesting finding of the study is the relationship between telomere length and bird survival, with those that died during the 8-year period after sampling having significantly shorter telomere lengths on average at the time of measurement. This suggests that telomere length may partially determine the life expectancy of giant petrels, independently of age and sex.

The southern giant petrel, a frequent victim of accidental capture by trawlers, is included on the Red List of Threatened Species maintained by the International Union for Conservation of Nature (IUCN). With an adult population that has fallen to 100,000, it is believed that thousands of these birds were killed inadvertently by illegal fishing vessels during the 1990s. In its future work, the team behind the study will focus on population genetics studies of colonies of giant petrels, a species with an extreme life-history strategy combining longevity and a low reproductive rate – females lay only one egg in each breeding season – that makes adults highly vulnerable to any type of survival threat.

Rosa Martínez | alfa
Further information:
http://www.ub.edu

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>