NEW BEARS ON THE BLOCK: What brought polar bears into existence some 150,000 years ago? Researchers are digging into DNA preserved in a rare bone to try to find out.
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Climactic changes might currently be threatening the survival of polar bears (Ursus maritimus), but similar shifts appear to have played an important part in bringing the species into existence in the not too distant past.
Researchers announced today that they have sequenced the mitochondrial genome of an ancient polar bear. The genetic traces they found in the bear's 110,000- to 130,000-year-old jawbone reveal that the species likely split from brown bears (U. arctos) just 150,000 years ago, at a time when specializing in arctic living quickly became an advantage rather than a liability.
The species' rapid evolution sheds new light on one of the emblematic species of climate change. Although the breed has become a popular flagship species for the issue, scientists knew little about how past climate affected the bear's evolutionary success.
The new genetic portrait gives a firmer frame to the polar bear's relatively rapid adaptations in the past. "From a conservation perspective it does tell us the polar bear has been through warming periods before," says Lisette Waits, a professor in the Department of Fish and Wildlife Resources at the University of Idaho, who was not involved with the research.
The bear's mitochondrial genome is the oldest one yet reported from a mammal—nearly twice as old as the mammoth genome. The results were published in the March 1 online edition of Proceedings of the National Academy of Sciences.
Parsing the polar bear
To arrive at the new portrait of polar bear evolution, the researchers used high throughput sequencing (a speedy DNA sequencing technique) to compare the genetic information gleaned from the ancient polar bear jawbone with that of six mitochondrial genomes of two modern polar bears and four brown bears from various habitats. They found that the polar bear whose jawbone was sequenced "existed very close to the most recent common ancestor of polar bears and brown bears." Previous estimates of polar bear evolution had placed the split any where from 70,000 years ago to more than one million years ago.
A mitochondrial genome does not give away physiological secrets like the more complete nuclear genome (such as the 4,000-year-old one recently completed for an ancient human). So the genetic fragments cannot tell us the color or thickness of this particular animal's fur. But it does lend some perspective to the genetic pedigree of the species and individual.
Judging from comparisons of modern bear genetics, it is estimated that the common ancestors of truly modern polar bears lived about 45,000 years ago, surviving what may have been a population bottleneck resulting from changing climate patterns.
Discovering the jawbone (from the bear's left mandible) was an accomplishment in itself. "Just finding such an ancient fossil was pretty magnificent," says Charlotte Lindqvist, a research assistant professor at the State University of New York at Buffalo and lead author of the study. As the researchers pointed out, because polar bears live primarily on sea ice, their remains often end up in the ocean. But this rare relic was found in 2004 on a small spit of land on the Norway's Svalbard Island.
Having been preserved in large part by the cold, dry climate, the fragment, which includes a canine tooth, still held some genetic remnants. "That was pretty astonishing as well," Lindqvist says. She and her colleagues were also able to ascertain a bit about the bear's eating habits. "From isotope analysis, we were able to get a good idea of its feeding ecology, and it fits very well at the top of the feeding chain of marine mammals" like polar bears today, she notes.
And even without the genetic revelations, the jawbone itself gives a few hints about the individual. "We can say it was probably a male adult polar bear of a size which can be found in modern polar bears and had a feeding ecology similar to today," Lindqvist says.
"I'm really impressed with their accomplishment," says Waits, who had previously published estimates about the genetic origins of polar bears that align closely with the new findings.
Kissing cousins
The news of these findings comes on the heels of a February report that grizzly bears have been encroaching onto polar bear territory in Canada's Wapusk National Park in Manitoba. The observation has concerned many conservationists, who worry about the grizzlies competing with—or even attacking—polar bears. But competitors though they may be, grizzly bears (being of the brown bear subspecies Ursus arctos horribilis) are such close relatives that the two species can produce fertile offspring.
The arrival of grizzlies into polar bear country opens up a fresh set of questions about the polar bear's genetic future in the midst of new discoveries about their past. "We know from earlier observation that polar bears and brown bears can hybridize, so there's a whole new potential for change in speciation or change in the polar bear gene pool or change in the brown bear gene pool," Waits says.
See what we're tweeting about
33 Comments
Add CommentMar 01, 2010
Reply | Report Abuse | Link to thisCoffee supplies hit by rising demand, climate change
04:51 PM
More coffee drinking coupled with climate change have reduced supplies of beans, producers said at an international conference over the weekend.
Fish are shedding their fins
Bears are losing their fur
Coffee prices are steadily rising--
Things that concurrently occur.
Under the aegis of global warming
Now more popularly known as climate change,
Developments that have received much attention
Even though to many observers they're strange.
Perhaps that may be the secret!
Because they're so doggone obscure
They can be sold by unscrupulous snake oil salesmen (and women)
As self-afflictions that only snake oil will cure..
Mar 01, 2010
Reply | Report Abuse | Link to thisCoffee supplies hit by rising demand, climate change
04:51 PM
More coffee drinking coupled with climate change have reduced supplies of beans, producers said at an international conference over the weekend.
Fish are shedding their fins
Bears are losing their fur
Coffee prices are steadily rising--
Things that concurrently occur.
Under the aegis of global warming
Now more popularly known as climate change,
Developments that have received much attention
Even though to many observers they're strange.
Perhaps that may be the secret!
Because they're so doggone obscure
They can be sold by unscrupulous snake oil salesmen (and women)
As self-afflictions that only snake oil will cure..
Here in Mytown, we've also had to adjust to climate change for a long time. In fact, we have this old saying: If you don't like the weather here in Mytown, stick around - it'll change!
Reply | Report Abuse | Link to thisAt least during the Little Ice Age nobody was arguing about the data...
There is no such thing as Evolution.
Reply | Report Abuse | Link to thishttp://www.fossil-museum.com/fossils/
Those several thousand examples should show you that things didn't evolve. Its hard Science. Its a common myth that there is such a thing as Evolution.
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Even your top advocate for Evolution is stopped in His tracks with the simplist of Questions.
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http://creation.com/was-dawkins-stumped-frog-to-a-prince-critics-refuted-again
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And Fossils are the way we can be there along time ago, there then, to see the ancestors.
Nice article, but it's 'climatic' not 'climactic'.
Reply | Report Abuse | Link to thisScott_G - You wouldn't be arguing this position to, say, maybe, support some contradictory mythology, would you? Why not just declare yourself instead of hiding behind something you declare to be hard science?
Reply | Report Abuse | Link to thisMarch 1 2010
Reply | Report Abuse | Link to thisAfter reading about your sequencing of the mitochondrial genome of an ancient polar bear is about as accurate as counting the mileage between earth and the farthest speck of light. It might have been the grizzly that evolved from the polar bear. Scientist just do not know.
Make it up as you go science. Repeat your ludicrous claims often enough and the Lemmings will believe it eh?
Reply | Report Abuse | Link to thisMake it up as you go science. Repeat your ludicrous claims often enough and the Lemmings will believe it eh?
Reply | Report Abuse | Link to thisAre the trying to make us believe that climate wont really make them go extinct? Because that's what it sound like. I didn't find anything else new or interesting in this article other then a hint of big companies behind it.
Reply | Report Abuse | Link to thisIt is certainly not about the bears. This is about abstract computer modeling being falsely elevated to the level of science and then presented as if it were science. Modeling produces objective computer generated conclusions based upon input assumptions and processing. In order for models to be approximately predictive, the assumptions must be realistic and work backward as well as forward. In most complex cases, modeling is GIGO. GIGO is their real value; eliminating hypothetical possibilities.
Reply | Report Abuse | Link to thisPolitics operates on GIGO propaganda - secondary causation not on first principles. Science or first principles do not affect government decisions in democracies. When a politically correct model gives bankrupt politicians an advantage to manipulate naive voters, truth and democracy become irrelevant.
Bear protection is all about a mass movement that intends to destroy global prosperity by crowd control in the brave new world. NIMBY is the unintentional foremost philosophy of the enemies of our prosperity but by putting bears on an endangered list when they are not endangered is ‘new speak’, mind-control, and secondary reasoning all wrapped up in one, and it intrusive into someone else’s (Nunavut’s) back yard to boot. Science should not be secondary to modeling under any serious circumstances because there is too great a likelihood of missed assumptions and empty logic rendering the conclusion dead wrong.
However, it is certainly not about the bears. This is about abstract computer modeling being falsely elevated to the level of science and then presented as if it were science. Modeling produces objective computer generated conclusions based upon input assumptions and processing. In order for models to be approximately predictive, the assumptions must be realistic and work backward as well as forward. In most complex cases, modeling is GIGO. GIGO is their real value; eliminating hypothetical possibilities.
Reply | Report Abuse | Link to thisPolitics operates on GIGO propaganda - secondary causation not on first principles. Science or first principles do not affect government decisions in democracies. When a politically correct model gives bankrupt politicians an advantage to manipulate naive voters, truth and democracy become irrelevant.
Bear protection is all about a mass movement that intends to destroy global prosperity by crowd control in the brave new world. NIMBY is the unintentional foremost philosophy of the enemies of our prosperity but by putting bears on an endangered list when they are not endangered is ‘new speak’, mind-control, and secondary reasoning all wrapped up in one, and it intrusive into someone else’s (Nunavut’s) back yard to boot. Science should not be secondary to modeling under any serious circumstances because there is too great a likelihood of missed assumptions and empty logic rendering the conclusion dead wrong.
It is certainly not about the bears. This is about abstract computer modeling being falsely elevated to the level of science and then presented as if it were science. Modeling produces objective computer generated conclusions based upon input assumptions and processing. In order for models to be approximately predictive, the assumptions must be realistic and work backward as well as forward. In most complex cases, modeling is GIGO. GIGO is their real value; eliminating hypothetical possibilities.
Reply | Report Abuse | Link to thisPolitics operates on GIGO propaganda - secondary causation not on first principles. Science or first principles do not affect government decisions in democracies. When a politically correct model gives bankrupt politicians an advantage to manipulate naive voters, truth and democracy become irrelevant.
Bear protection is all about a mass movement that intends to destroy global prosperity by crowd control in the brave new world. NIMBY is the unintentional foremost philosophy of the enemies of our prosperity but by putting bears on an endangered list when they are not endangered is ‘new speak’, mind-control, and secondary reasoning all wrapped up in one, and it intrusive into someone else’s (Nunavut’s) back yard to boot. Science should not be secondary to modeling under any serious circumstances because there is too great a likelihood of missed assumptions and empty logic rendering the conclusion dead wrong.
Jtdwyer, It never crossed my mind to include God in the argument against Evolution or Global Warming.
Reply | Report Abuse | Link to this---
If you want to Pray and Ask God if he exists, no one is stopping you.
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As for Evolution, as I said, the Fossils prove otherwise. Not one or two, not forgeries, but thousands upon thousands.
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As for Global warming, I did the math, you could raise the oceans 7 meters if you could melt all of greenlands Ice.
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But the southern part of it, is melting about 1 meter a year. And its 3KM thick. That means if ALL of it melted, it would take 3000, years. Fortunately, Science and weather will not let that happen. The tilt of the earth and the temperatures ect. Will only let portions of it melt, and then they will be replaced. And some of that 3KM of Ice is also below sea level, so that portion won't raise sea levels either.
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You should be able to google it, even Wiki will tell you these things if you read down a little.
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The truth is, genetic information came, and then it has been degrading ever since.
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The Truth is the Trilobite which is one of the first things in the fossil record had complex eyes, like the Bee today. So things were complex from the start.
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Reveiw the fossil record, find everything from fish to crabs, to flys, even plants, with NO change over 100's of millions of years. Even with all the climate change, and movement of the plates, and changes in the Enviroment.
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http://www.fossil-museum.com/fossils/
I happen to put in Heat pumps, and have a Patient on some Grout, and I love the fact people are into saving energy. But lets not lie to each other.
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Wind power amounts to bird blending machines that only work here and there, and need the whole carbon based system anyways.
And Solar Power, only works during the day. and when no snow is on the PV panels. who knew.
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Geothermal Heatpumps work, and pay for themselves in 7-10 years.
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The ONLY invention worth researching is a PV panel that can be used with Nuclear waste. If that can be rolled up into a battery. We would have cars that recharge, by themselves, and last 10 years without fuel.
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It does work, but the PV panel material decays to fast. But, when thats fixed. The world will change.
Scott_G - You've certainly convinced me with your fantastically factual proclamations. I had done the math, too, but I had miscalculated. I am now ready to receive whatever wisdom you subscribe to, but I still don't know what it is. Thank you so much.
Reply | Report Abuse | Link to thisScott_G - I do apologize for my rude witless sarcasm. Sometimes it unfortunately gets the better of me. You have every right to express your own opinion. I'm sorry.
Reply | Report Abuse | Link to thisThis article once again rides the coattails of climate change headlines with only the weakest association to it. The only real connection I can find is the presumption that the genetic changes of mitochondrial DNA, from which no associated climatic adaptations can be determined, is the product of climate change, and a few young conservationists apparently looking to qualify for a climate change funding grant, like everyone else. The use of climate change to publicize this research could have been justified if it had determined some specific adaptations that could be directly attributed to specific climatic changes, but this is not the case.
Reply | Report Abuse | Link to thisHow long does it take to get a different breed of dog, eg poodle?
Reply | Report Abuse | Link to thisThe planet has been warmer in the past, CO2 levels are believed to have been 5x and 20x higher in ancient past. Will 0.3x be a disaster?
Will weapons of mass destruction becoming easier to make become a disaster? What will happen if any bright kid with a million dollars can gene splice his own "better" yeast that turns into a fast spreading killer.
I do not see how this has anything to do with computer models being some part of a giant conspiracy, the only connection this has with climate change is that apparently polar bears are more adaptive than we thought.
Reply | Report Abuse | Link to thismultilis: There was a time when CO2 levels exceeded 2,000 ppm, more than 6x higher than today. Do you know what also happened at that time? The Great Permian Extinction, when nearly everything on the planet was wiped out. To say that Anthropogenic Climate Change could do that would be complete BS, the highest, absolute worst case scenarios I've ever seen put the figure at 80% of all life being wiped out, but I think that is overly pessimistic. However, super high CO2 levels, coupled with other effects also triggered by the Siberian Traps, are believed to have been the primary cause of the Great Permian Extinction.
There Is no Climate change. Weather for the History of Mankind has been Crazy. Its the nature of it. In one moment, a Chili Earthquake can move an ocean of water, changing thing. The Moon could line up and increase the tide, A forest fire, a Volcano, a Solar event, extra cloud cover can change the BTUH entering or exiting this planet. Winds Change, and Flip around causing Snow on a whole Continent and the Reflection removes Trillions of BTUH's from our planet. These things line up randomly.
Reply | Report Abuse | Link to this----
We have no choice over the Sun. We cannot control or be responsible for everything.
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And to think A bear changed because of a bit of weather, because of a false theory of Evolution proven False by the Fossil record is just one more unscientific notion propigated by People who happen to go to school and call themselves scientists.
I was looking forward to an erudite article about the evolution of polar bears published by none other than Scientific American, when, to my utter dismay, in the very first sentence, incredulous, I read the word "climactic" instead of the correct--in this context--"climatic".
Reply | Report Abuse | Link to thisHow anti-climactic! Shame on you, Scientific American!
Oh, here the come, the legions of dimwits. This article's really bringing them out: you get the morons who think they've got some clue as to the reality of climate change and the drooling religious idiots who know literally NOTHING about evolution and think that's enough to disprove it. It never ceases to amaze me that after billions of years of evolution, there are still humans that are as utterly stupid as some of those that post on this forum. Even better, these are people who ignore evidence and eschew scientific advancement and knowledge...but they still populate a forum on the topic. It's almost like they've been lead here like sheep by their cosmic zombie voodoo priests to come and try and refute reality...which, of course, they find terribly scary and confusing. That's why they turned to christianity in the first place.
Reply | Report Abuse | Link to thisSad, pathetic creatures, still mired in the thinking produced in the smallest, most reptilian portion of their brains. They lash out at anything that contradicts their worldview, and the more evidence you have against it, the harder they scream and gnash their teeth. It's okay, though, we're winning. Their numbers are diminishing every year. Each new generation brings fewer and fewer religious nutjobs into the mix...which is why the world is continually becoming a better and better place. If we can keep them from destroying the world for another couple of decades, we might just be able to pull out of this dive and achieve a world without religion...a world of peace, morality and freedom.
Yeah, I know...it's an insane idea, but hope springs eternal!
Hey spoonman, this one's for you!
Reply | Report Abuse | Link to thishttp://spq.sagepub.com/cgi/content/abstract/0190272510361602v1
I looked for some religious stuff, to see if there was any actual evidence for that prayer stuff, I mentioned you could try to find out if God existed, If thats your thing. I found these these three Items that as close to evidence as I could find.
Reply | Report Abuse | Link to thishttp://www.tangle.com/view_video.php?viewkey=9172a7a5bc47b0890074
http://www.tangle.com/view_video.php?viewkey=96b28bcf34828e67b040
http://www.youtube.com/watch?v=7CIHPor_haA
I think the Fossil record is a much better hands on argument against Evolution. The Live video and personal accounts are much harder to believe.
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As for this Bear being evolved. I don't see any evidence supporting that Idea, and no chain of fossils over the years to prove it.
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Also here is another problem with UnScientific facts.
The age of the Universe and the size of the universe make it impossible for us to see the stars, yet we do.
http://en.wikipedia.org/wiki/Age_of_the_universe
http://en.wikipedia.org/wiki/Observable_universe
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The Universe is too big and moving away from the centre too fast. That means the Light from the stars we see would be stopped in time and space. The Red shift doesn't make sense.
Infact. It means the age part, adding in the folding of space etc, makes the Big Bang theory false.
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In simple terms. If you are traveling 100 miles an hr. and throw a ball out the back window at 100 mph. the ball will remain Stopped compared to that location. So, that would mean, Light leaving stars traveling away from us at the speed of light or even 1/2 that speed, would not be seen, and wouldn't have reached us. That means, these stars which we see, are already far far farther away than what we see, and that they are not moving away as fast as some Science says.
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That means the Universe is 100's of times Older than it is. OR that the Universe was as Neuton said, before he was hoodwinked to believe in the Big Bang, was Large, was already out there, and then started expanding.
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And that means what we see in space has been there for 10 to 100 times longer than we thought, and everything from Carbon Dating, the age of our sun etc. is wrong.
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How does this relate to Bears. The Whole Evolution Religion is propogated by Priests we call Scientists. The Catholic Church used to hoard information, Till the Printing press, took the Bible away from their hands so that people would make up their own minds. Then progress was made.
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Likewise the Internet, formal Education and the Utube etc, takes the control of Truth away from false science.
wow......please turn off your computer man....i mean just wow...
Reply | Report Abuse | Link to thisyou're joking right? no one is this dumb?
I agree that cosmologists and astrophysicists are far from figuring it all out, and much of what they think they know is wrong. But that's just me, and I haven't figured the universe out yet, either. I can tell you with certainty that its far more complex than you now imagine.
Reply | Report Abuse | Link to thisVery simply, if you throw a ball out the back of a car, it will be traveling at a speed determined by the speed of the car and the its speed relative to the speed of the car (keeping direction of motion in mind). It will not be motionless relative to the Earth. These things are far trickier than they seem: you have to keep after them.
Scot G that is going on fundies say the darnest things!
Reply | Report Abuse | Link to this@Scott_G, please consider for one moment that the reason science doesn't make sense to you is because you are ignorant. That's ok. I am ignorant of lots of stuff too. I am ignorant of many sports, like Cricket for example. Cricket makes no sense to me. Still, you won't find me trolling Cricket sites telling them that Cricket isn't a sport, or that the rules of Cricket are all wrong. I acknowledge my ignorance and defer matters of Cricket to those that care. You are ignorant of evolution, cosmology, science in general and rational thought. But for some reason you seem to think that your minutes of dedicated research and regurgitation of tired creationist arguments will somehow pursuade us that all science is wrong. Keep in mind that most of us are interested enough in science to have at least read one or two books on the subject. And the scientists who you claim, "just happened to go to school", have actually done much more than that. Instead of wasting their time squatting in a church, grovelling for forgiveness, they have actually done real science; that means field work, experiments, analysis; then submitted their work for review by their peers. They didn't just steal everything from a Watchtower pamphlet or creationist blog. The power of science is that it is a transparent process that can be followed by anyone, rather than an arbitrary set of rules, dictated by self-proclaimed spokesmen for God Inc. We spent the last century fighting dictators. Why do "the faithful" submit to them so easily?
Reply | Report Abuse | Link to thisThe extent of your delusion is incredible. It borders on mental illness or intellectual defect. If so, sorry, we can't do much about the cards we are dealt. The best thing you can do for yourself is, instead of starting with a proposition which you desperately need to have validated, study what defines a logical argument. Read about logic, critical thought and logical fallacies. Study the scientific method, not just what it is but how it came about. Then let those guide you to the truth. Science doesn't tell us the answers; it shows us how to ask questions. On the other hand, religion doesn't allow us to ask questions, it dictates the answers. The rule-of-thumb I try to live by is, the idea that you should trust the least is the one you find easiest to believe.
I think the title of this piece is trying to mislead us into believing that global warming, er climate change will change the polar bear, but really it is talking about the past 150,000 years. So really, this article really posits that global warming er climate change will NOT endanger the polar bear...
Reply | Report Abuse | Link to thisJust a couple of quick thoughts:
Reply | Report Abuse | Link to thisa) Why are polar bears white? Because they do most of their hunting from ice. It is already common for polar bears to fast through late summer, when there is no ice they can swim to that also has seals around it. Obviously, there is a limit to how long an animal can fast. So, as summer sea ice melts earlier and refreezes later, there will be less of an advantage to being a white bear.
b) Dunning-Kruger rules the day.
Your idea that there is no such thing as evolution is ludicrous in and of itself. I know that the creationist community passes off as fact that evolutionary scientist are stumped and made speechless by creationist questions but that is a creationist myth. An evolutionary scientist could only be made speechless by the sheer adacity and lack of intellectual honesty by creationist claims.
Reply | Report Abuse | Link to thisour idea that there is no such thing as evolution is ludicrous in and of itself. I know that the creationist community passes off as fact that evolutionary scientist are stumped and made speechless by creationist questions but that is a creationist myth. An evolutionary scientist could only be made speechless by the sheer adacity and lack of intellectual honesty by creationist claims.
Reply | Report Abuse | Link to this@Chris G,
Reply | Report Abuse | Link to this"b) Dunning-Kruger rules the day."
You can say that again. Notice all the instant physicist and biologists that have suddenly sprouted.