Wednesday, December 15, 2010

Global Warming Impacts - Arctic Cross-Breeding

Polar bears breeding with grizzlies, bowheads breeding with right whales, narwhals with belugas, even porpoises with seals.   This is apparently going on in the Arctic.

In a commentary published in Wednesday's peer-reviewed journal Nature, National Oceanic and Atmospheric Administration marine biologist Brendan Kelly and his co-authors say rapidly disappearing sea ice means the barrier that once kept Arctic species apart is literally melting away.

" In addition to that, marine mammals are particularly infamous for hybridizing,"  says Kelly. " It turns out their genes haven't changed so much that they can't interbreed."

Co-author David Tallmon, a marine biologist with the University of Alaska, says while it's unlikely hybridization is widespread in the Arctic, no one has looked systemically at the issue. He and Kelly, along with Andrew Whiteley, a conservation geneticist at the University of Massachusetts, say the question of whether to try to stop animals from crossbreeding needs immediate attention.
" It's likely to become increasingly important as the summer ice diminishes and is ultimately lost,"  says Tallmon. " Hybridization is essentially impossible to reverse once it has begun on a large scale. So, we want to be sure to halt any hybridization before it becomes unmanageable and unique lineages are lost forever."


Read more: http://www.cbc.ca/technology/story/2010/12/15/science-arctic-hybrids.html#ixzz18D6wBHIy

5 comments:

doconnor said...

I'm pretty sure porpoises can't breed with seals. Porpoises are in order Cetacea which includes whales, but seals are in order Carnivora which includes wolves, tigers and bears. The only thing they have in common is that they are both mammals who live in the water.

The Mound of Sound said...

I know, that one sounded pretty dodgy to me too. Narwhals and Belugas, however, that sounds doable if they're really, really careful.

LMA said...

Isn't it just possible that interbreeding may allow these animals to adapt to changing conditions? Why oh why do humans always feel the need to manage nature? We have already altered the climate and created a situation which requires these animals to adapt, now we are going to interfere because we want to preserve "unique" lineages? Then we will have to build bigger zoos to house these lineages because their natural habitat will be gone. Haven't we have already done enough damage?

The Mound of Sound said...

I think the fear is that this isn't an evolutionary thing, a way that creatures adapt, as much as it is climate change-driven, essentially man-made, and that it may have disastrous impacts on the original species. I see their point.

LMA said...

Yes, I made the point that this hybridization is not a natural process, that it is driven by climate change, but nonetheless I feel we should leave the situation alone. The original species are facing extinction in any case because of loss of habitat due to AGW. There is no chance of evolutionary adaptation for these animals because global warming is happening too fast. Maybe nature has another plan, and for once we should stop trying to manage other species.