Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Loss of Arctic Ice May Promote Hybrid Marine Mammals

16.12.2010
Scientists have expected for some time that the Arctic Ocean will be ice-free in summer by the end of this century. Writing in today’s issue of the journal Nature, a trio of researchers say the seasonal loss of this ice sheet, a continent-sized natural barrier between species such as bears, whales and seals, could mean extinction of some rare marine mammals and the loss of many adaptive gene combinations.

Marine mammalogist and first author Brendan Kelly of the National Oceanic and Atmospheric Administration’s marine mammal lab in Juneau, with conservation geneticist Andrew Whiteley of the University of Massachusetts Amherst and evolutionary biologist David Tallmon of the University of Alaska, say genes developed over millennia in isolated populations have given many Arctic marine animals sets of fine-tuned adaptations, helping them uniquely thrive in the harsh environment.

Their article for the first time looks ahead to speculate on what biologists can expect as these populations meet, hybridize by interbreeding and mix their gene pools.

The authors call for immediate monitoring and stepped-up study of many already rare, threatened or endangered bears, whales and seals in the coming decades, before discrete populations begin to disappear through interbreeding.

As Whiteley explains, the picture is complicated and it is hard for biologists to know exactly what to expect because hybridization can have beneficial consequences in the first generation. But in later generations, the process begins to have more negative effects as genomes mix and any genes associated with environment-adapted traits are recombined. Genes related to any trait that once allowed the animal to thrive in a specific habitat can be diluted, leaving the animal less well suited to surviving and reproducing there.

In some cases hybridization, which is one of nature’s sources of evolutionary novelty, might not be so bad, the authors acknowledge. But in other cases such as interbreeding between the rare North Pacific right whale, with fewer than 200 individuals believed to be left, and more numerous bowhead whales, interbreeding could mean extinction of the rarer, smaller population.

In a chart accompanying their Nature article, Kelly, Whiteley and Tallmon identify 22 marine mammal species they believe may be at risk of hybridization. They report that several Arctic hybrids have been documented already by DNA testing. For example, hunters shot a white bear with brown patches in 2006 that later was confirmed to be a polar bear-grizzly bear hybrid.

At UMass Amherst, Whiteley’s usual primary research interest is in exploring questions related to a variety of species in Massachusetts and elsewhere, such as how evolutionary fitness works in wild populations and the effects of habitat fragmentation and climate change on species’ evolutionary potential.

Andrew Whiteley | Newswise Science News
Further information:
http://www.umass.edu

More articles from Earth Sciences:

nachricht Filling the gap: High-latitude volcanic eruptions also have global impact
20.11.2017 | Institute of Atmospheric Physics, Chinese Academy of Sciences

nachricht Antarctic landscape insights keep ice loss forecasts on the radar
20.11.2017 | University of Edinburgh

All articles from Earth 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

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>