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From National Geographic

Week before last, temperatures in International Falls Minnesota reached 46 degrees below zero and that was the air temperature, without the windchill.  An Arctic blast of cold air broke free from its northern moorings and spread rapidly into Minnesota and nearby states. At those temperatures, breathing through your nose is a challenge, as ice crystals form within the nasal cavity and you quickly find it best to breathe through a scarf or some other device, like a face mask that quickly gets warmed by your breath. But in time, even these filters develop ice crystals and breathing through them can become more labored. Most Minnesotans know what to do under these conditions–they go outside only when they have to and spend more time indoors. Air hockey anyone?

All humans share a short nasal cavity; sufficient time has not elapsed to see if evolutionary adaptations might arise in Minnesotans, such as a longer nasal cavity that would serve to mitigate nasal ice crystal formation.  In response to this dry arctic air that crept into Minnesota week before last, I found myself shuttered inside, thinking about polar bears and the special adaptive features they have developed to make it through winters that actually don’t get a lot colder than what we observed recently in Minnesota (January temperatures in the Arctic get to about 58 degrees below zero, so we truly got a blast of real Arctic air), though they stay that way much longer. Polar bears are insulated by about 4 inches of blubber, lying immediately underneath their skin. They also have a larger head and a longer nasal cavity when compared to Brown bears. The longer nasal cavity is probably better at warming the cold air when breathing through the nostrils and polar bears have an olfactory apparatus that can detect minute odor levels miles away.  You have heard of the infrared cameras that one uses to gauge heat loss and identify areas in your home that are losing heat through poor insulation. Well, the polar bear is so well insulated that they are virtually invisible to an infrared camera. They are one of the most efficient animals for heat retention we know of.

Polar bears are the largest land-dwelling carnivores, with males reaching up to 1500 pounds; the largest polar bear on record weighed 2210 pounds. Yet, while they are the dominant predator of the Arctic circle, they are slated for extinction perhaps within the next 50 years. A guaranteed disappearance of a predator at the top of the food chain should bother the Hell of out of all of us, because we are predators at the top the biggest and widest food chain in the world. So if polar bears can disappear with the speed of essentially dimming a switch, why can’t this happen to us just as easily? Well of course, for one thing there are more of us–humans number more than 6 billion and by the middle of this century we are scheduled to reach 9 billion, while polar bears, restricted to the Arctic circle region, number about 20,000 to 25,000; their numbers are already declining while human numbers continue to grow. Then too, we occupy a different niche than polar bears and occupy more temperate zones and insure ourselves an adequate supply of food through agriculture and animal cultivation; most of us don’t have to hunt to eat. In contrast, the polar bears have an established a food chain niche that is critically dependent on the retention of sea ice for foraging. This projected elimination of the species is not because of threats from hunting or factors other than the expected conditions that will be brought about by global climate change and the early seasonal loss of sea ice that polar bears depend on for hunting their primary prey–seals. Persistent sea ice is essential for polar bears to hunt. Normally, the sea ice doesn’t break up until September, at which time polar bears are forced by circumstances to move off the sea ice onto land. In the fall, a pregnant female creates a hibernation den within the snow and enters into a state of semi-hibernation during which time, her cubs are born (2-4) and they feed exclusively on mother’s milk for three to four and a half months.

When a mother polar bear comes out of her winter hibernation, with cubs in tow, she will have lost several hundred of pounds of weight, as she had fattened up before hibernation in order to nurse her cubs that are born during the hibernation period. After the birth of the cubs, but still during the hibernation period, mother’s milk is the exclusive source of nourishment used to feed the cubs. So when she emerges with her cubs in the spring, they are old enough to have some mobility and her first need is to get food to nourish herself and keep producing mile to feed her cubs. It’s as if the termination of the hibernation period brings on a food crisis. Normally, when polar bears emerge from hibernation,  the arctic sea ice is still intact, which is far more conducive for catching seals, the main diet of polar bears.  Even when the sea ice begins to break up in the summer, large chunks of ice allow polar bears to hunt on the ice when seals break through their holes to breathe. But if the sea ice becomes too thin and breaks up into smaller chunks or disappears altogether, seals are no longer constrained to breathe through the ice and polar bears can no longer hunt efficiently.  There are reports of polar bears mating with grizzlies, the result of which is to produce hybrids that are less efficient as swimmers and at greater risk when marginal sea ice conditions appear.  So, the earlier that the sea ice melts or breaks up, the greater is the risk for polar bears. Reports of polar bear drownings have already appeared, presumably as a result of too much ice melting and making swimming distances between ice flows too great.

The story behind the threat of polar bear extinction began  in 2007 and was provided by a report from the U.S. Geological Survey (USGS), indicating that within 50 years, the shrinking sea ice will leave only a small remnant of polar bear populations on the islands of the Canadian Arctic; those along the Alaskan and Russian coasts, which are the populations most often studied, will all be gone. These reports were provided to Congress; a year later, the polar bear was listed as a threatened species under the Endangered Species Act by the United States Department of the Interior.

The report of 2007 made the news in the Anchorage Daily News (article written by  Tom Kizzia, September 8, 2007) and, until recently, nothing had changed to alter these grim projections, based on scientific expectations derived from climate change modeling studies, using what is known as a general circulation model (GCM). Those studies indicated that sufficient carbon dioxide had already accumulated such that a “tipping point” had been reached and nothing could be done to reverse the fate of sea ice in the Arctic as it was shrinking at a much faster rate than earlier models had predicted. In a relatively short time, it was predicted that sea ice would disappear and get broken up earlier and earlier in the year, putting more pressure on polar bears. In these studies, the tipping point concept was based on the idea that ice normally provides a reflection of sunlight and thus returns energy from the surface of the earth, preventing some solar radiation from warming the oceans and land surfaces. But as ice surfaces diminish in area, earth and water surfaces get more sunlight exposure. This phenomenon is referred to as the “albedo” effect; it constitutes a positive feedback from melting ice–the more ice that melts, the more sunlight hits the earth and water surfaces and in turn melts more ice. The ice melt of 2007 was especially worrisome. Thus, USGA report of 2007 suggested that this positive feedback system, had already reached a point that future sea ice would melt, perhaps very rapidly, and eliminate most of the polar bear population within 50 years. According to that report a tipping point had already been reached so that no matter what future reductions in carbon emissions might be achieved, the polar bears were doomed.

The 2007 USGA report was not seriously challenged until a recent article appeared in Nature in December 2010 (volume 468, p. 955-958). This report re-examined the idea of a tipping point for sea ice and the future of polar bears. However, in these new modeling studies, the issue was examined based on the assumption that some reduction in greenhouse gases would take place in the future. Using a similar model to that used to project a poor outcome for polar bears, the paper by Amstrup et al accepted different levels of reductions in green house gases as a basis for generating different models that simulated whether or not a normal  sea ice pattern could be retained under these conditions of reduced carbon dioxide emissions. Five different models of reduced carbon emissions were used, including one proposal to keep the carbon dioxide levels the same as those of the year 2000 (Y2K model); other models used different scenarios for reducing the level of carbon emissions. First, this study confirmed the 2007 USGA results, strongly supporting the idea that if nothing is done, most polar bears are either doomed or will have to dramatically change their hunting habits (and are probably poorly equipped to do so).  However, with reductions in atmospheric carbon dioxide, the Amstrup modeling studies showed that the sea ice could be retained sufficiently to give safe harbor for polar bears. They did not find a “tipping point” that doomed the polar bears and for that reason alone, the study was very encouraging and carried an obviously reduced doomsday prediction. The December 2010 study is exemplary for several reasons. In addition to giving new hope to the polar bears if humans begin to reduce carbon emissions, the Amstrup paper also demonstrates the power of the internet. In a high impact journal such as Nature, papers are given a relatively small amount of space for a single paper–typically three pages or less for an article. But, because information can be stored on the internet, referred to and linked/downloaded while reading the on-line paper, the so called supplemental material can increase the length of the paper by several fold. The polar bear paper referred to was less than three double-sided printed pages in the magazine, but the supplemental material, which contained additional information on the models used, including more color figures and references, was 26 double-sided pages. A second mode of expansion can be seen in the reference section, where if you click on the section, it expands so that each reference has a “show content” link that takes you to an expanded explanation of the reference that has been quoted, what the reference says and why it may or may not be a source of valid observations and conclusions. In short, the Nature paper just described shows why there are no short papers anymore, particularly on a complex subject and within a high impact journal. Now we have three different levels of readership. First, there’s the casual reader, trying to get the general concept of the article, then there’s the serious reader who evaluates the main figures and can talk somewhat intelligently about the article and then there are the global climate change people and serious polar bear biologists who scour through the main article, all the figures, the material in the supplemental section and the expansion of the references, a sort of “why did I use this reference” section. The take home message of all this complexity is that first and foremost, the best and worst case for the future of our polar bears are both based on models–that is all we have to go on. But, increasingly, the models are fed by better and better data and such models are trying to reach down and resolve time limits not achieved in previous work. Instead of centuries long outcomes, models are getting down to half-century and even decades of time. We will see some of these changes within a single human lifetime. But, a single year of weather means nothing–the variables making up our annual weather patterns are too great to project our future from the weather that unfolds in a single season, tempting though it may be to project them forward in time. I seriously doubt that humans have the capacity to remember and log the long-term weather patterns, such that we can become reliable reporters of weather patterns that change over decades: most of us can’t really remember with certainty the weather events of last year. We remember really tough winters and hot summers and there is a sense that we are moving towards warmer conditions, but these transitions are not smooth hyperbolic curves we ride on and that’s why, as much as we like to talk about the weather, we rely on measurements to reveal the true weather trends. Those measurements show, that as the carbon dioxide emissions have increased, the air temperatures are rising, our oceans are warming and expanding, the ice masses are receding and species are threatened. Globally, 25% of mammalian species are threatened with extinction. Habitat loss is the main reason and for the polar bears, the threat of loss of sea ice is also a case of habitat loss, even though it is first and foremost attributed to global climate change and humanoid activity.

RFM

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The BP Macondo oil well that ruptured in the Gulf of Mexico on April 20, 2010, was capped on August 5, 2010, after five million barrels of crude were added to the waters of the gulf, fouling 632 miles of Gulf beach, including parts of Louisiana, Mississippi, Alabama and Florida. This oil spill, the largest oil leak in our history, will have an incalculable impact on the indigenous animal life, including the humans that populate the region or attempted to take a vacation in the area during the malevolent, visible violence of the oil surge. But, what our mainstream press want us to believe is “out of sight, out of mind,”  which doesn’t actually work when you live in the region and try to make a living from the traditional mode of fishing and shrimping. According to the reports we hear, the oil  is gone now thanks to the cleanup crews and the dispersant Corexit, which was liberally applied both deep, at the site of the oil leak, and on the surface. Writer Terry Tempest Williams spent time, beginning July 28, 2010 visiting the region, particularly Louisiana, which was hardest hit by the continuous movement of oil from the site of its release. Williams has written a searing piece in Orion Magazine describing her own experiences in the region and how she and her small crew got contaminated and had to go through detox process. Her article is entitled “The Gulf Between Us.” It is a passionate and well written account of her experiences and views as an environmentalist and activist. The reason we don’t hear more stories about the downside of the Gulf is that BP demands a confidentiality agreement from everyone they compensate, and since just about everyone in the region was affected in one way or another, there is a wide, effective gag order imposed on the very people that have to continue trying to make a living in a region damaged in ways that we may never understand. Yet these are the people that know most about the impact of the spill and Williams gives them voice in her article.

So, if we wanted to conduct an experiment on the environmental impact of a major oil spill–now is our chance. But BP is attempting to silence the scientists who are examining the impact of the spill, as I wrote earlier. Whatever we have done to the ecology of the region will not be known for decades and many issues will probably never be fully understood. Right now, thanks to the use of Corexit, there is a layer of oil on the bottom of the Gulf, the magnitude and distribution of which is presently unknown: I seriously doubt there is any method that can measure it.  But that is the area where many fish breed (including some species of blue fin tuna), so the future of fish that spawn in the gulf is unknown and since the number of fish caught is rapidly diminishing world wide (virtually all Atlantic salmon that we buy in the store is farmed fish), it will be hard to pin any change in fish numbers on the Gulf oil spill of 2010.  Not entirely unrelated is how we destroyed the cod fishing in the North Atlantic: once fishing trawlers came along that could reach with their nets down to the bottom of the ocean, the cod started to disappear because that’s where the big cod go down to breed and where the newly hatched cod stay to grow. So, while cod was once considered to be an inexhaustible source of seafood, and built the early economy of New England, the major cod fisheries have been closed since the early 1990s. Will oil on the bottom of the gulf achieve what the trawlers did to the cod fishing industry in the Atlantic?   Williams’ article also reveals that many residents of the Gulf region have been tested for contamination and show up with elevated levels of benzene and cadmium. So, we haven’t just intoxicated the wild life of the region, we must also think about the long-term impact on humans. Williams adds another point that should spark instantaneous sobriety: the five million barrels of oil spilled into the gulf would have provided the United States with about four hours of our daily oil diet. It is government collusion with the oil industry that produces this kind of outcome, though many feel that BP is an outlier when it comes to safety issues. The PBS program FRONTLINE did a major documentary on the safety record of BP and its convoluted history. You can watch it here. I have also commented on BP and the Gulf oil spill in articles here and here.

Who can lead us out of this toxic quagmire of excessive, American-style capitalism that puts humans below profits and stock values over human safety and protection of the environment? It is as if our frontal lobes, the region of our brain where we stand the best chance of evoking some longitudinal thinking and perhaps realizing that we are on an unsustainable path–that region of the brain has died of the atrophy of disuse, especially by our government and its collusion with international corporate objectives. But, as the saying goes, “we have met the enemy and it is us.” If we demanded a change and forced refocus of our culture on a sustainable path, compatible with the environment and the other animals that live within it, we could change things beginning now. We are too late to avoid impact from global climate change and we are too late to avoid a rise in sea levels, but we are not too late to save the planet from an insurmountable catastrophe that lies in our path if we do nothing. If we should lose the Greenland, Antarctic and Arctic ice, the ocean levels will rise by about 70 meters, Florida will be completely underwater and the Mississippi River will drain into the Gulf at Tennessee. While the earlier projections did not foresee this kind of catastrophe during the 21st century, the ice is melting faster than we thought, by mechanisms we cannot yet model, nor do we understand. So, while it is still true that we control our own destiny, that is probably only true today for a subset of the global population. It doesn’t mean we can’t improve, but we are already late.

RFM

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Our most effective pollinator, the honey bee, has been dying off in massive numbers through an unknown process described as Colony Collapse Disorder (CCD): bees leave the hive and don’t return, while the hive is essentially destroyed as member numbers decline. CCD has not shown any signs of decline over the years and represents a serious threat to the future of our food supply, as about 1/3 of the food we eat depends on pollination from bees. The almond business in California has been especially hard hit by this problem, as almond trees need massive levels of pollinators during a short critical period; honey bees are now delivered by trucks during the pollination season, but the spreading nature of CCD has caused almond tree farmers to destroy many of their trees for lack of access to pollinators. Some trucks arrive with bees that themselves experience CCD during the almond pollination season. The problem is not just confined to America, but has also seriously impacted Europe, asia and India. Multiple, different explanations for massive bee hive loss have been suggested, including fungal, viral and mite disease and also the possibility that bees are more stressed due to the collective load of pesticides, herbicides and other unidentified toxic chemicals that are increasingly abundant in our environment. The idea is that bees leave the hive in search of food but get disoriented because of the disease and die far removed from the hive. For that reason, the sick bees are hard to study because they get lost.

A recent  NYT article describes a possible breakthrough in discovering the etiology of CCD.  The Times article was based on an extensive study described in the on-line science journal Plos One (public access is available). The combined force of academic researchers and a group of army researchers studying proteomics, extensively analyzed  and compared stable, unstable and collapsed bee colonies. They used a very powerful method of mass-spectrometry based proteomics. With this approach, instead of looking for genomic evidence, they were able to analyze thousands of different proteins and infer back to identify the organisms that generated them. The field of proteomics has exploded in the last decade and is becoming an increasingly powerful way of looking at gene control through analysis of the proteins they generate. Although many pathogens have already been detected in bees and many were also discovered in the Plos One study, two different organisms seemed to consistently track one another and correlate best with CCD, including a large DNA virus, not described in bees previously, and referred to as the invertebrate iridescent virus (IIV; Iridoviridae); however samples also consistently contained a microsporidia Nosema apis (fungus); the co-localization of these two pathogens was more consistent with CCD than either one alone. Once a hive was infected, forager flights began to decline, as dead honey bee samples showed increasingly high peptide counts from the two pathogens. Using pathogen injections into single bees (see figure), they were able to show that bee toxicity was far more evident when both pathogens were injected as opposed to either one alone.

Injection of single bees

The take home message from this study is twofold: first MSP is a powerful tool for studying the pathogenic origins of bee infections and secondly, perhaps a dual infection with a previously unknown (in bees) large DNA virus (Iridoviridae) and a  fungal agent (Nosema apis) accounts for beehive collapse in America. The authors are quick to point out that  CCD in other countries may be attributed to different pathogens and that their analysis may only account for the problem in North America. It is still not clear whether the dual infection is the cause of CCD or whether it is a sign of imminent colony collapse, but the injection studies certainly point to these two pathogens as the cause rather than an indicator. The obvious question is that if the double pathogen theory is correct, how can CCD be treated and can beehives be restored to centers of industry and productivity? Many workers in the field seem to believe that treating the fungus may be the best approach, but as the graph shows, fungus control alone may not solve the entire problem. Injections with either pathogen reduced bee lifespan over controls. Perhaps on the way to recovering normal beehive function, we may have a period in which beehive lifespan is reduced, while still serving a pollinating function. The other possibility that is difficult to eliminate is that healthy bees can effectively fight off these infections, while bees that are environmentally intoxicated through other means cannot. Thus, one can ask whether CCD in North American bee colonies reflects the globalization of pathogen exposure or have these pathogens always been in the environment and now have opportune moments for bee infection, because their hosts decline in health through other mechanisms? Only time and a lot more research can answer these questions. The good thing about the Plos One report is that a new bee pathogen has been discovered and it may hold important clues to the future of pollination and the security of our own food supply.

Let’s see now, how would the free market  respond to the pollination problem we are facing in America? No, they would not invest in the development of electronic pollinators because the development time is too long (remember that the lifespan of a CEO is about five years, so investment must yield something substantial within that time frame).  Only the shaky and uncertain thrust of venture capitalism would respond with long-term investments and the hope of a payoff down the road. That sector of our financial repertoire  is about the only healthy element  that remains, but it is too small to be a broadly effective source of financing.  In the meantime, thank God we have a government who will support these studies, though I find it worrisome that a U.S. Army MSD apparatus was necessary, rather than having one available to the scientists on their own, together with the expertise required to run the machine and interpret the data. This is what happens when grants get cut to the bone and research is limited because of limited funding. I counted eighteen authors on the Plos One article and thirteen different institutional locations. A problem of the depth and magnitude of CCD can only be approached through highly collaborative scientific efforts.  CCD is truly one of the more profoundly disturbing components of our modern culture and, in my view,  should be ranked with global climate change as a looming threat for which we need to mobilize a strong research effort, preferably one that doesn’t require the American military. On the other hand this story represents a good union of vital resources and technologies that proved essential to unravel this part of what remains as a serious whodunit problem.

RFM

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