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    Climate Change Implicated In Polar Bear Stress
    By News Staff | January 25th 2014 11:06 AM | 12 comments | Print | E-mail | Track Comments

    A group of researchers say they have established a new biomarker for how stressed polar bears are about climate change.    

    Last year, a team reported that fluctuations in climate and ice cover are closely related to stress among polar bears in East Greenland as indicated by levels of the stress hormone cortisol in hair samples. The team is hopeful this type of analysis will be beneficial once others learn that it can now be done with much greater reliability.

    "Nobody else has done this so far," says Jerrold Meyer of the University of Massachusetts Amherst, who calls himself a behavioral endocrinologist. "We've not only been one of the key developers of the technique but we have also have worked very hard to demonstrate its reliability and validity. In collaboration with Melinda Novak, chair of the psychology department, we were among the first to show in a major controlled study that a prolonged or major life stress does lead to a demonstrable increase in cortisol in hair. Now we're making the technique available to others and we hope it spurs new collaborations with our lab."

    Meyer says that over the past 40 years techniques have become not only much more sensitive and precise, but safer for researchers as they have been able to move away from using radioactive substances. "We can now measure much lower levels of substances than we could when I was a grad student," he recalls. "And with new enzyme immunoassay techniques read by a microplate reader, the work has become not only safer for researchers, but for lab workers and the environment."  

    To analyze cortisol levels in hair, the researchers need a sample about 3 cm long and weighing about 5 mg, that is, 10 or 12 strands. In humans, this amount cut from the scalp outward represents about three months of hormone activity as human hair grows an average 3 cm per month, Meyer notes. In his UMass Amherst lab about six undergraduates are currently learning the exacting techniques for washing and drying samples, grinding them to powder, extracting the cortisol, and conducting the enzyme immunoassay.

    For the collaboration with Thea Bechshøft of Aarhus University and colleagues, Meyer's lab received blind hair samples from 88 polar bears legally killed between 1988 and 2009 in Greenland by indigenous people who have an arrangement with researchers to provide biological samples. Cortisol will persist in hair for hundreds of years, Meyer explains. 

    "We have analyzed this hormone in several blind samples of polar bear hair from museum specimens that were killed and stuffed in the late 1800s, and we had no trouble measuring it 125 years later," he says. "Others have measured cortisol concentrations in Peruvian mummies 1,500 years old. It's one of the beauties of hair cortisol, you can measure it in archival specimens."


    Citation: Meyer, J., Novak, M., Hamel, A., Rosenberg, K. Extraction and Analysis of Cortisol from Human and Monkey Hair. J. Vis. Exp. (83), e50882, doi:10.3791/50882 (2014).


    Comments

    And 31 years of needless CO2 panic to billions of innocent children is a war crime for history to judge.
    Not one IPCC warning ever agreed beyond "could be" yet you "believe".

    Hank
    Do you have anything constructive to ask or comment about this study, or do you just go around the Internet alleging 9/11 Truther-type conspiracies about neuroscience?
    Yes, Kyle. Agree with the premise of the study, or shut up. It's a very scientific ultimatum, you see.

    Hank
    Well, no, but this gives me a chance to flesh out the point. By spamming articles with irrelevant nonsense and vitriol, it makes any climate skepticism look like it's all idiots just parroting the same talking points over and over. There are legitimate criticisms of this study that could be made but every commenter is just busy saying how stupid climate science is, and not a single one has a clue about how to interpret a result, much less make a model.

    The anonymity of the Internet gives you the comfort of sniping people without any recourse - but it just makes you look like a crackpot. Make your own model and show it to the world. Instead of dumping on science, do some and show us all how to to it right.
    Here’s the reality Hank.

    If you’d like to be thought of as a semi-intelligent authority figure on the matter, then it’s important for you to begin to use words correctly. For instance, “spamming” would entail endless postings for free trips to Hawaii, work-at-home opportunities, and male enhancement supplements. “Spamming” does not at all entail the posting of comments and opinions that you may find disagreeable, even if they remark on the preposterous nature of the entire concept as a whole, and even if those comments contain vitriol. Thought I’m not quite sure what is more vitriolic and anti-scientific than calling people “idiots” or “crackpots.” Traditionally name-calling has existed primarily in the realm of the adolescent high school and grade school student, so these kinds of hyperbolic errors places you directly into the “crackpot” bin as well. Remember, anyone can run a website.

    Attempting to force a commenter into a position where they are expected to comment on the nature of the study when the entire underpinning concept is highly suspect, facilitates dishonest debate. It’s essentially the same as demanding someone comment on the culture of the fairies captured in the Cottingley photographs, and then calling them cranks if any of them dare point out that the fairies were hoaxed to begin with. At the end of the day, much of what passes for “climate science” is in fact deeply stupid. Furthermore, a person need not know how to read a Richter Scale to know when an earthquake is occurring.

    The anonymity of the Internet also gives me the ability to protect myself from intolerant zealous activists who are becoming increasingly willing to do harm to anyone who expresses views contrary to their own belief system. While I'm certain that you may consider inflicting "recourse" onto your debate opponents to be an integral part of today's scientific method, remember, anonymous speech has a long and proud history going back to the pamphleteers of the American Revolution, perhaps earlier, and has provided society with many benefits by allowing unpopular opinions to be voiced in openly hostile climates.

    Besides, putting forth the effort to create a model to prove this flim-flam is analogous to spending the time to create a model proving the migration patterns of the chupacabra. Thinking people don’t need politically motivated and funded models to understand what pure bunk is.

    Hank
    Spare us all the amateur invective. In reality, you hide behind anonymity and childish posturing because you don't know what you are talking about. 

    If you read the article beyond the title, and have basic reading comprehension, you would know that your claim about "the entire underpinning concept is highly suspect" is gibberish. You are contending that science cannot measure the levels of cortisol in hair samples, which means you are clueless.
    Remember when science had some semblance of respectability? Been awhile. Since global temperatures have been flat for the past 9-17 years depending on who's data you examine then once should expect no particular alarm from polar bear hair samples collected recently. Or perhaps the stress has more to do with the number of nature photographers snapping photos of them while they are trying to eat. The scientific community is well on it's way to losing the last few shreds of credibility that may remain.

    Amen, DC!
    With no religious connection inferred!

    Seriously?
    The fact (maybe) that polar bears are stressed out some time in their (hair) lives (not to be confused with their entire lives) is some sort of unequivocal proof that climate change is the source of their stress?
    This doesn't even rise to the level of straw grasping!
    Eighty eight bears legally killed, right?
    That means they were hunted.
    You don't think that might have been just a bit stressful?
    The tenuous, if not vacuous, links by researchers eager to dip into the "climate change" budget has become one of the most laughable pursuits in science these days!

    More of these cracked urns that call themselves scientists from what assilum did these nuts come from?

    I wondering how they are going to determine what the stress was caused by? Attributing stress to changes in climate seems a stretch to me. How do they control for mating season, competition for food and other factors? I would think these things would be difficult to determine in archival samples.

    "The polar bears will be fine" - Freeman Dyson commenting to calm his wife's concerns over algore's movie.