Thursday May 15, 2008, 10:26 am
Polar bears and Grizzlies were the same species 100,000 years ago. They have probably been interbreeding forever, like dogs and wolves. Just because we just noticed it, doesn't make it a sign of doom.

Friday May 16, 2008, 7:52 am
More unfounded made up "facts" by Judy ROFL

Friday May 16, 2008, 8:15 am
Judy you remind me of those whom, as they were leading the Jews into the gas chambers, told them that everthing was fine & that "this" wouldn't hurt at all. Mankind is leading Mother Earth into the gas chamber. I was also wondering why you are even on this site. I thought it was for people who care about the Earth & all the creatures & plants that live within the Earth's atmosphere. It seems you don't quite fit into that quality of caring.

Friday May 16, 2008, 8:41 am
Oh, really now! That is just a bit much! Carrying on about "gaschambers' when the reality about CO2 is that it is a beneficial trace gas.
You guys are the ones in league with the extermination plan.

I care about the Earth enough to put up with abuse from know-nothings like you.

As for the relationship between Polar Bears and Grizzlies...

Evolution of Polar Bears
The fossil transitions leading to our knowledge of development of the Polar Bear species are very well documented. Bear fossils change through time; i.e., as higher levels of sediments and sedimentary rocks are examined, more recent fossils are found. For most of the transitions from one species to another, there is a well characterized series of transitional specimens leading right across the species "boundaries" Kurten (1976).

Somewhere during the mid-Pleistocene period (roughly 100,000 to 250,000 years ago), a number of brown (same as grizzly) bears (Ursos arctos) probably became isolated by glaciers. many probably perished on the ice; however, they apparently did not all disappear. Some survived due to the fact that "organisms vary" (Steve Gould's terminology and logic is used here), that is, every litter of grizzly's has a variation in coat thickness, coat color etc. which imparted a slight evolutionary advantage to some indivials of each litter. These successful individuals underwent an apparent rapid (rapid, probably because of the small population, and extreme selection pressure) series of evolutionary changes in order to survive (note they were not necessarily "better" in any absolute sense, or on any absolute "bear" scale of perfection - they were simply more in keeping with their new environment than their siblings). Today, polar bears are adapted to their harsh northern environment.http://www.geol.umd.edu/~candela/pbevol.html

Friday May 16, 2008, 6:37 pm
Mass extinctions have resulted from past warming events, so it certainly can happen again...

Fossil Study Links Extinctions to Warming

Four of the five major extinctions over 520 million years of Earth history have been linked to warmer tropical seas, something that indicates a warmer world overall, according to the new study published Wednesday.

http://www.care2.com/news/member/537645068/557088

Polar bears are just "the tip of the ice burg" - this just happens to be ONE species getting official recognition (there are many more going completely unnoticed)

The other trubbeling thing is that green house gasses are higher now than they have EVER been in 800,000 years! Polar bears (or other species including man) have NEVER seen these conditions before!!!!!

Greenhouse Gases Highest For 800,000 Years-Study

Carbon dioxide and methane trapped in tiny bubbles of air in ancient ice down to 3,200 metres (10,500 ft) below the surface of Antarctica add 150,000 years of data to climate records stretching back 650,000 years from shallower ice drilling.

http://www.care2.com/news/member/537645068/744364