Excerpts: from the Sunday Times: Polar bear is a ‘new’ species
by Jonathan Leake
Polar bears may have come into existence only 150,000 years ago, when trapped brown bears had to adapt to an ice age
Polar bears may have come into existence only 150,000 years ago, when brown bears were trapped by an ice age and had to adapt quickly to survive, scientists have found.
The suggestion follows the discovery of the jawbone of an animal that died up to 130,000 years ago, making it the oldest polar bear fossil found. The bone has yielded new insights into the origins of Earth’s largest land predator.
One is the possibility that polar bears owe their existence not only to past climate change, including ice ages, but have also survived at least one long period of global warming.
The bone was discovered at Poolepynten on the Arctic island of Svalbard by Professors Olafur Ingolfsson, of the University of Iceland, and Oystein Wiig, of the University of Oslo.
…
In a paper they said: “Brown bears of the ABC islands may be descendants of ancient ursids [bears] that diverged from other lineages of brown bears and subsequently founded the polar bear lineage.” This view is expected to get support from new research, out this week, based on DNA extracted from the Poolepynten jawbone.
It means polar bears have already survived a global warming that affected the northern hemisphere from 130,000 to 115,000 years ago, when the Greenland ice sheet and the Arctic ice cap were smaller than now. Professor Chris Stringer, of the Natural History Museum in London, an expert in ice ages, said: “Early polar bears would not have had all the specialisations of modern animals and we know nothing about their behaviour.
“Living through a warm period back then does not mean they are resilient to climate change now.”
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
land;
Since all of your assertions are false, I’ll restrict myself to the final one.
“Population centers” in the Arctic are minuscule. And warming provides MUCH MORE food for the bears, not less. Though the bears like town dumps, because they don’t run away or hide. But that’s just a few percent.
Polar bear populations are booming, and will continue to do so.
rbateman (10:21:59) :
“Seems to me I watched a special where Polar Bears that bore their young in an ice-free environment had cubs that were brown. As if they are programmed to adapt to whatever the cycle is doing.
So, do humans revert back to neanderthals in an ice-age?”
Given Al Gore and his lemmings, I would say we are already showing signs of reverting.
Pat Moffitt (11:39:11) :
“DeNihilist
The most dangerous teaching of Darwin was that species are merely a taxonomic human convenience. We draw lines where often there are none. The hybrid polar/ brown bear shot was fertile. In the old days before the definition of species evolved- this would imply that brown bears and polar bears are the same species.”
Yes isn’t it interesting that the polar bear is considered a separate species from the brown bear yet a caucasian and a negro are considered the same species even though the evolutionary mechanism that caused the development of both “whites” is the same: migration to a different niche environment where lack of pigment is advantageous, or at least not lethal.
Yup; it’s all sliding scales and mixes of slightly and significantly different genes. So we may end up ignoring species and just worrying about the survival of particular genes, since we’ll be able to mix and match them at will anyway.
Lots of possibilities! If tyrannosaurs had feathers, why not grizzlies? And so on …
LOL
I know this is sacrilege to environmentalists but the picture of the brown bear and the polar bear made me wonder about the scientific basis of the Endangered Species Act.
The polar bear emerged as a species 150,000 years ago as an adaptive response to ice age glaciation. The brown bear adapted to a niche environment to take advantage of the opportunities this environment had to offer. Several thoughts come to mind:
1) It shows the flexibility of a species genes to adapt to a changing environment. It is still a brow bear that just happens to be white now and has developed skills to hunt seals instead of being an opportunistic omnivores like its southern cousins.
2) It suggests the brown bears that turned into polar bears were less competent than their southern cousins. The ice ages didn’t descend in a day; there had to be thousands of years where the less competent bears were forced into marginalized conditions by other more aggressive members of their species. Life had to be much easier to he south, how did polar bears wind up in the far north? Only the timid fled north.
3) Animals and plants that live in niche environments are Nature’s losers. They evolved from more robust members of their species but they fell short in some way. They adapted themselves to live in niche environments because the better members of their species didn’t wanted to live there. That makes them fragile for a good reason; Nature has put them on the path to extinction. We only meddle with Nature by forestalling the inevitable.
4) What is a species? The cute polar bear you see? It’s just as reasonable to say the physical embodiment an an animal, plant or us is Nature’s way of replicating chromosomes. Like all living things we are born, we procreate and we die; just like Mayflies we serve our duty and then die. Would the hypothetical “Man from Mars” report back that chromosome replication is the essence of the life process or say it’s observed physical body?
5) If the purpose is to pass on chromosomes, then the matter of how that’s accomplished takes on less significance. Polar Bear or California Condor, it doesn’t matter. One is a bear, the other is a bird. Both are Nature’s losers because they were forced by inherent incompetence to conform to a niche environment. Birds, brown bears, rats, cockroaches and others will always prosper because are potent and virulent species. They may have offshoots but Nature prunes that tree.
6) So what’s the Endangered Species Act about? It’s purpose is to act against Nature and not cull out Nature’s mistakes. The Sacramento Delta Smelt is a perfect example. It is a perfectly useless niche environment little fish. It evolved from more competent smelt. It is one of Nature’s mistakes. Because of it, billions of gallons of fresh water everyday wash out into the Pacific instead of being diverted south into aqueducts. The San Joaquin Valley, the breadbasket of the US is going to desert and it is to no good purpose.
Mariss;
Concerning #3;
How do you think superior species evolve? Sometimes the adaptations the marginalized populations develop turn out to have wider value and benefit. The theory of “punctuated evolution” suggests that small isolated groups evolve fastest, and some end up with traits that lead to general dominance. A particular group of pre-humans were probably reduced to a small group on the west coast of Africa at one point, and changed enough to open up evolutionary paths to dominating the planet much later.
But >99.9% fail and die out. In other words, there are (at least) 1000 species gone extinct for every one that is still around.