So in celebration of one of the greatest ideas ever put forth Discovery ran a show called Evolutions on 3 animals and how they've evolved into the modern Turkey, Whale, and Bear. They showed how a wolf sized land animal turned into the modern whale, etc.
Anyways, the polar bear was descended from the brown/grizzly bear because it got separated by ice and became genetically isolated from the brown bear. It grew a biggers stomach, better nose, clear outer coat etc.
With the shrinking ice, the Polar bears have now come in contact with there cousins the brown bear. Looks like they've started actually mating...enter the GROLAR Bear. Some scientists are thinking this could be a new species of bear and that we're actually witnessing evolution in action. The fact that the polar bear became isolated only a couple thousand years (IIRC) and evolved this fast and are that adaptable is astounding.
I'm just a simple engineer, but this is absolutely fascinating to me. I just caught the end of the show (PVR'd) so I will have to watch it again. Anyone else heard about this bear??
There really isn't anything all that special about this bear. The Grizzly bear and Polar bear habitat have always crossed over. What is new is a confirmed case in the wild and has a lot more to do with advances in genetics that have made tests for this kind of stuff easier.
It sounds like they have made up this backstory about ice clearing and evolution as some kind of political point about global warming.
Cross breeding does not equate to evolution, forward or backward.
The rapid evolution of the polar bear is definitely fascinating, but this thing is pretty normal. The only thing that makes it unusual is the relative low numbers of both species which mathematically limits how often this can happen.
__________________ I am in love with Montana. For other states I have admiration, respect, recognition, even some affection, but with Montana it is love." - John Steinbeck
Yup, as species diverge it's not unusual for them to crossbreed. Speciation isn't a hard line it's fuzzy. A population that gets separated and starts to diverge will go through stages from easily breeding with each other to more difficult, to offspring being sterile, to not being able to breed at all.
Ring species are a good example of this.
__________________ Uncertainty is an uncomfortable position.
But certainty is an absurd one.
Yup, as species diverge it's not unusual for them to crossbreed. Speciation isn't a hard line it's fuzzy. A population that gets separated and starts to diverge will go through stages from easily breeding with each other to more difficult, to offspring being sterile, to not being able to breed at all.
Ring species are a good example of this.
I had my doubts, but the fact you have a learned looking man smoking a pipe as an avatar has convinced me.
Evolution in Reverse/Action...Grolar Bear
