Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UT researcher sheds new light on hybrid animals

18.09.2007
Recent findings raise new questions for conservation of endangered species

What began more than 50 years ago as a way to improve fishing bait in California has led a University of Tennessee researcher to a significant finding about how animal species interact and that raises important questions about conservation.

In the middle of the 20th century, local fishermen who relied on baby salamanders as bait introduced a new species of salamander to California water bodies. These Barred Tiger salamanders came into contact with the native California Tiger salamanders, and over time the two species began to mate.

"To give you a sense of the difference between these two species, they are about as closely related as humans and chimpanzees," said UT assistant professor Ben Fitzpatrick, a faculty member in the Department of Ecology and Evolutionary Biology.

Mating between two different species creates a hybrid offspring. According to Fitzpatrick, while such hybrids have been found to be successful in plant species, research has generally shown that animal hybrids are not able to sustain themselves -- in scientific terms, they lack "fitness."

This understanding made Fitzpatrick's findings especially surprising when he looked at the offspring of the two salamander species in California. He and colleague Bradley Shaffer of the University of California, Davis, found that the new hybrid salamanders were not only surviving, but in some cases, thriving.

"I thought I was studying hybrid dysfunction going into this study -- looking at how hybrids go wrong," said Fitzpatrick. "The level of vigor in these hybrids was completely unexpected."

Their research, funded by the National Science Foundation and the Environmental Protection Agency, will appear in the upcoming issue of the Proceedings of the National Academy of Sciences. It is among the first to show hybrid vigor among animal species, and Fitzpatrick noted that the work raises a number of questions for conservationists.

The California Tiger salamander, which is native to the area of the study, is listed as threatened under the U.S. Endangered Species Act, while the Barred Tiger salamander is not. The data in the article lead the researchers to predict that eventually all California Tiger salamanders will have some of the non-native genes. In a sense, the entire species would then have hybrid ancestry.

According to Fitzpatrick, the finding raises questions about whether this would be considered beneficial to the native species or not -- it depends on how conservationists choose to define the new hybrid.

"If they consider it an acceptable modification of the original species, then this could enhance the chances for survival of the California Tiger salamander," he said, "but others may consider the hybrids to be genetically impure and see hybridization as accelerating extinction."

It is not yet clear from the research what is causing the hybrids to thrive.

"Our prediction is that, because of their advantages, the hybrids will remain part of the gene pool," said Fitzpatrick. "What we don't know is if those advantages come from the synergistic interaction of certain genes -- that they are greater than the sum of their parts -- or if they simply get the 'best of both worlds' by a selection of useful individual traits from each species."

Because the research is in such early stages, Fitzpatrick and colleagues plan to broaden their study of these salamanders, and also explore the implications of these vigorous hybrids for other animals in their ecosystem.

They have expanded the number of genetic markers that they are analyzing in the hybrids to determine the extent of their genetic mixing. Given that the new hybrids are finding more success in their environment, the researchers also plan to study whether their success is reducing food supply or other resources from native species in the area.

Fitzpatrick notes that their discoveries place the work on the leading edge of hybridization studies.

"We're right at the front in thinking that these ideas may be much more generally applicable," he said. He pointed to two other studies in recent months that have explored the issue of hybridization in butterflies.

Jay Mayfield | EurekAlert!
Further information:
http://www.tennessee.edu

More articles from Ecology, The Environment and Conservation:

nachricht Scientists team up on study to save endangered African penguins
16.11.2017 | Florida Atlantic University

nachricht Climate change: Urban trees are growing faster worldwide
13.11.2017 | Technische Universität München

All articles from Ecology, The Environment and Conservation >>>

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 >>>