A Project of Sage Steppe Wild
I didn’t know that the huge cave bears were vegetarians. Changing climate wiped out their food.
Story on the extinction of cave bears. By Alister Doyle, Environment Correspondent. Reuters.
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Dr. Ralph Maughan is professor emeritus of political science at Idaho State University. He was a Western Watersheds Project Board Member off and on for many years, and was also its President for several years. For a long time he produced Ralph Maughan’s Wolf Report. He was a founder of the Greater Yellowstone Coalition. He and Jackie Johnson Maughan wrote three editions of “Hiking Idaho.” He also wrote “Beyond the Tetons” and “Backpacking Wyoming’s Teton and Washakie Wilderness.” He created and is the administrator of The Wildlife News.
Comments
Research into human genetic markers has shown that early human ethnic groups in Europe/Asia migrated back and forth to stay on the edge of the ice as it advanced and retreated. Perhaps the size of the bear and its reliance on caves prohibited this on the grand scale. In addition, it is hard to imagine a modern brown or black bear surviving a hard winter without the pre-winter access to meat based protien and fat, be it grubs, ground squirrels. salmon or fawns.
Good story, The human population such a long time ago would be more hard pressed to cause the extinction of an entire species all by themselves compared to how easily we can and do have an effect with our overpopulation of today.
The problem with these models that attempt to explain certain species going extinct due to climate change always run into the same dilemma.
As with the mastadon, dire wolf, camels, and other species that went extinct 10,000-30,000 years ago, many climatologists have claimed it was the last ice age (and subsequent climate change) that caused the extinction of these species.
However, not a single one of these studies claiming it was the climate has ever successfully explained why these same species survived many other ice ages of the same duration and severity. Ice ages have come and gone many times during these species time.
Yet, it was the last one that killed them off? Why this last one and not the dozens of other ice ages that preceded it?
Until this question is answered to science’s satisfaction, I would caution anyone to believe the “climate change killed them off” theory.
It is simply incomplete and lacks the proper evidence to back it up. A very interesting debate to be sure, but one that is still raging with no end in sight, despite all the studies that keep surfacing one way or the other.
Mike said: “In addition, it is hard to imagine a modern brown or black bear surviving a hard winter without the pre-winter access to meat based protien and fat, be it grubs, ground squirrels. salmon or fawns.”
Mike, the species living in North America 10,000-25,000 years ago have lived through many ice ages.
Yet, those species always survived all those previous ice ages by adapting successfully.
The question is, what was different about this last ice age? Science still debates this question quite rigorously, and the camps are still split between those that think it was climate change, and those that think the human presence made the difference in the high extinction rates.
Both sides of course think they are correct, but no one has demonstrated concrete proof of either theory. There seems to be contradictory evidence of both, so perhaps there is a middle ground between them.
We may never know conclusively.
I theorize that it was more likely a combination of factors. Granted, they had survived previous ice ages, but I would assume they (like every other living thing) has continued to evolve between them. Perhaps between the previous ice age and the one where they went extinct, they changed in a way that would make them more vulnerable to an ice age. At the same time, perhaps they were coming under increasing pressure from those pesky humans. There may have been geographical changes that prevented most of the population from moving away from the spreading glaciers at the same time and or segmented the population to the point that it could not maintain genetic diversity.
We are looking at the same time of thing (on a smaller scale) with the grizzlys. Pine beetles are killing off a large portion of the white back pines that they need for a protein boost in the fall. People are constantly nibbling away at their available habitat and we have created huge barriers to their ability to migrate to other areas, both for more readily available food and to provide the genetic diversity that a species must have to survive in the long term.