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Grolar Bears and Narlugas: Rise of the Arctic Hybrids
#1
Grolar Bears and Narlugas: Rise of the Arctic Hybrids
Grolar Bears and Narlugas: Rise of the Arctic Hybrids
By Bruce Barcott
December 15, 2010
Science & Technology Nature & Wildlife

Climate change appears to be igniting a sexual revolution among Arctic mammals -- and that’s not good news for some endangered species.

In 2006 an American hunter shot an animal in the far north of Canada’s Northwest Territories that shared characteristics of a polar bear and a grizzly. Earlier this year, a similar bear was killed less than 200 miles away, and DNA tests confirmed it was a mixture of the two species. The "grolar bear" thus joined a growing list of cross-species couplings -- beluga whales and narwhals, right whales and bowhead whales, various seal mixtures -- all confirmed to varying degrees by scientists in the Arctic over the past two decades.

What’s going on here?

In the December 16 issue of Nature, three American researchers argue that global warming is encouraging the formation of hybrid offspring among Arctic mammals. "The rapid disappearance of the Arctic ice cap is removing the barrier that’s kept a number of species isolated from each other for at least ten thousand years," says the article’s lead author, University of Alaska evolutionary biologist Brendan Kelly. That’s leading to some unusual pairings that could have dire consequences for endangered species in the Arctic.

http://www.onearth.org/article/grolar-be...ic-hybrids
The world is a dangerous place to live - not because of the people who are evil but because of the people who don't do anything about it.
- Albert Einstein
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#2
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
So, let me get this right. Some animals are now getting opportunities for sex with other animals that previously they couldn't.... and this is a bad thing?

Surely this is just survival of the (ex)-species? Endangered species coming together to create new species which will survive the changing environment better and increase the overall base population?

And regardless of whether the polar caps changing is a natural thing or a man made thing, its not the first time in the history of the earth that the polar caps and shrunk or expanded.

All sounds like hysteria.
A finite number of monkeys with a finite number of typewriters and a finite amount of time could eventually reproduce 4chan.
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#3
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
(December 16, 2010 at 8:52 am)Loki_999 Wrote: All sounds like hysteria.

Which part?
The world is a dangerous place to live - not because of the people who are evil but because of the people who don't do anything about it.
- Albert Einstein
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#4
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
(December 16, 2010 at 10:00 am)lilyannerose Wrote:
(December 16, 2010 at 8:52 am)Loki_999 Wrote: All sounds like hysteria.

Which part?

If you bemoan the fact that habitats and species composition is changing from what is really a very transient state which you so happened to think is the normal, then I don't share your alarm. There is no special validity in your normality. The state that is coming is as normal for a future age as the state you bemoan is for yours.

If you bemoan the fact that human economy, political boundary, and infrastructure was built around the state that you think is normal, and bemoan the high cost to human of economic realignment, social and political instability, and infrastructural early obsolescence, then I share your alarm. There is economic merit in holding on to this normality.



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#5
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
Polar bears evolved when a population of brown bears was cut off by glaciation.

http://www.geol.umd.edu/~candela/pbevol.html


What nature gives it also takes.

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#6
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
It's been a long held observation of mine that we don't necessarily want to "protect" anything...we just don't want it to change. People are like this in social settings too.

Suppose the rising temperature is both a combination of human and natural factors. We reduce our carbon footprint but the temps keep rising. No use bemoaning that the Earth USED to be a particular way. Shit changes. Adapt.
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#7
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
Creationist lunatics aside, the whole point of evolution by natural selection is that organisms evolve to deal with the conditions they are in. Those with the most beneficial adaptations survive to reproduce UNTIL conditions change again. Then, all bets are off and organisms must evolve again.
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#8
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
I found it of interest as I was not aware that adaptation to environment would occur so quickly. I do have a tremendous interest in science without the background so I also wonder what has "triggered" this adaptive reproduction in the animals?

The world is a dangerous place to live - not because of the people who are evil but because of the people who don't do anything about it.
- Albert Einstein
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#9
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
(December 16, 2010 at 2:51 pm)lilyannerose Wrote: I found it of interest as I was not aware that adaptation to environment would occur so quickly. I do have a tremendous interest in science without the background so I also wonder what has "triggered" this adaptive reproduction in the animals?

Lack of suitable mates often trigger the adaptive behavior of looking further afield and/or accepting less suitable mates. This could extend to mating outside the traditional mate pool. This results in testing of the definition of species. Traditionally a species of sexual organisms like humans, dogs and bears is defined to be any population sufficiently similar genetically and behaviorally so that when individuals of different sex of breeding age are brough together, they can mate and produce offspring that are both viable and fertile.

Clearly polar bears and brown bears can mate. The important remaining question remaining is are the hybrids of polar and brown bears viable and fertile? If they are, then in fact polar bear and brown bear represent merely major variations within same species, in principle similar to, but of a greater degree then, the variation between different population of human beings. In this case the mating is merely the continuation of the species and is no threat to any species. It may alter some traits of the resulting population, but that is just an exhibit of microevolution within species in response to conditions, sort of like creation of new breeds of dogs, or new population of humans resulting from intermixing of different previously isolated populations.

If the hybrids are not fertile or viable, then that proves our classification of them as different species to have been correct, and brown and polar bears are of different species. Their offspring with either die before mating, will not be able to mate, or will sire no offspring from any mating attempt. In this case, the presence of hybrid polar and brown bears is evidence of a threat to the continued existence of both species because because each act of such mating wastes the parents' mating capacity in producing hybrid offspring that can not carry on the species past their own lifetimes, but will potentially still compete with really viable and fertile offsprings for resource.




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#10
RE: Grolar Bears and Narlugas: Rise of the Arctic Hybrids
Quote:Lack of suitable mates often trigger the adaptive behavior of looking further afield and/or accepting less suitable mates. This could extend to mating outside the traditional mate pool. This results in testing of the definition of species. Traditionally a species of sexual organisms like humans, dogs and bears is defined to be any population sufficiently similar genetically and behaviorally so that when individuals of different sex of breeding age are brough together, they can mate and produce offspring that are both viable and fertile.


Thank you!

The world is a dangerous place to live - not because of the people who are evil but because of the people who don't do anything about it.
- Albert Einstein
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