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 p
|Contact: Jay Mayfield|
University of Tennessee at Knoxville