Climate Change Increases Risk of Crop Slowdown in Next 20 Years

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The world faces a small but substantially increased risk over the next two decades of a major slowdown in the growth of global crop yields because of climate change, new research finds.The authors, from Stanford University and the National Center for Atmospheric Research (NCAR), say the odds of a major production slowdown of wheat and corn even with a warming climate are not very high. But the risk is about 20 times more significant than it would be without global warming, and it may require planning by organizations that are affected by international food availability and price.”Climate change has substantially increased the prospect that crop production will fail to keep up with rising demand in the next 20 years,” said NCAR scientist Claudia Tebaldi, a co-author of the study.Stanford professor David Lobell said he wanted to study the potential impact of climate change on agriculture in the next two decades because of questions he has received from stakeholders and decision makers in governments and the private sector.”I’m often asked whether climate change will threaten food supply, as if it’s a simple yes or no answer,” Lobell said. “The truth is that over a 10- or 20-year period, it depends largely on how fast Earth warms, and we can’t predict the pace of warming very precisely. So the best we can do is try to determine the odds.”Lobell and Tebaldi used computer models of global climate, as well as data about weather and crops, to calculate the chances that climatic trends would have a negative effect of 10 percent on yields of corn and wheat in the next 20 years. This would have a major impact on food supply. Yields would continue to increase but the slowdown would effectively cut the projected rate of increase by about half at the same time that demand is projected to grow sharply.They found that the likelihood of natural climate shifts causing such a slowdown over the next 20 years is only 1 in 200. But when the authors accounted for human-induced global warming, they found that the odds jumped to 1 in 10 for corn and 1 in 20 for wheat.The study appears in this month’s issue of Environmental Research Letters. It was funded by the National Science Foundation (NSF), which is NCAR’s sponsor, and by the U.S. Department of Energy (DOE).More crops needed worldwideGlobal yields of crops such as corn and wheat have typically increased by about 1-2 percent per year in recent decades, and the U.N. Food and Agriculture Organization projects that global production of major crops will increase by 13 percent per decade through 2030 — likely the fastest rate of increase during the coming century. …


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Temperature and ecology: Rival Chilean barnacles keep competition cool

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Here are two facts that make the lowly barnacle important: They are popular models for ecology research, and they are very sensitive to temperature. Given that, the authors of a new study about a bellwether community of two barnacle species in Chile figured they might see clear effects on competition between these two species if they experimentally changed temperature. In the context of climate change, such an experiment could yield profound new insights into the biological future of a major coastline that is prized for its ecological, aesthetic, and economic values.But in the study to be printed in the April 2014 issue of the Journal of Experimental Marine Biology and Ecology, the scientists found no significant effect of temperature on competition at all. That surprising non-finding may have its own implications.”The dominant if somewhat dated narrative in marine ecology, and ecology more broadly, is that competition is a major structuring force in natural communities,” said co-author Heather Leslie, assistant professor of environmental studies and biology at Brown University. “We know it’s a more nuanced story, but to find cases where it’s a bit of a draw is really unusual.”Moreover, temperature did not turn out to be the mediating factor.”Temperature wasn’t the beast that we often think of it being, which in itself is surprising,” Leslie said.Plenty of studies of other co-occurring barnacles would have suggested otherwise. In the North Atlantic, there is a well-documented and clear dynamic between two barnacle species, the little gray barnacle (Chthamalus fragilis) and the northern rock barnacle (Semibalanus balanoides). The little gray barnacle can only survive high up on the rocks, where it is hottest and driest, because farther down it gets thoroughly routed by the northern rock barnacle. Temperature, in other words, provides the little gray’s only refuge.The picture in Chile was downright unclear. Previous studies had yielded conflicting hints about how temperature might affect the competition between two southern hemisphere barnacle species, Jehlius cirratus and Notochthalamus scabrosus. Led by Emily Lamb, who began the work as a Brown undergraduate concentrating in environmental science and is now a research assistant at the Estacin Costera de Investigaciones Marinas (ECIM) in Chile, the team devised an experiment to get a more definitive answer.Made in the shadeLike their northern cousins, the Chilean barnacles Jehlius and Notochthalamus live in a clearly stratified society with Jehlius more abundant higher up and Notochthalamus more abundant lower down into the tide. …


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Water samples taken from the Upper Ganges River shed light on the spread of potential "superbugs"

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Experts from Newcastle University, UK, and the Indian Institute of Technology in Delhi (IIT-Delhi), reveal the spread of antibiotic-resistance to one of the most pristine locations in Asia is linked to the annual human pilgrimages to the region. The research team are now calling on governments around the world to recognise the importance of clean drinking water in our fight against antibiotic resistance.The spread of antibiotic-resistance to one of the most pristine locations in Asia is linked to the annual human pilgrimages to the region, new research has shown.Experts from Newcastle University, UK, and the Indian Institute of Technology in Delhi (IIT-Delhi), sampled water and sediments at seven sites along the Upper Ganges River, in the foothills of the Himalayas.They found that in May and June, when hundreds of thousands of visitors travel to Rishikesh and Haridwar to visit sacred sites, levels of resistance genes that lead to “superbugs” were found to be about 60 times greater than other times of the year.Publishing their findings today in the journal Environmental Science and Technology, the team say it is important to protect people visiting and living at these sites while also making sure nothing interferes with these important religious practices.They argue that preventing the spread of resistance genes that promote life-threating bacteria could be achieved by improving waste management at key pilgrimage sites.”This isn’t a local problem — it’s a global one,” explains Professor David Graham, an environmental engineer based at Newcastle University who has spent over ten years studying the environmental transmission of antibiotic resistance around the world.”We studied pilgrimage areas because we suspected such locations would provide new information about resistance transmission via the environment. And it has — temporary visitors from outside the region overload local waste handling systems, which seasonally reduces water quality at the normally pristine sites.”The specific resistance gene we studied, called blaNDM-1, causes extreme multi-resistance in many bacteria, therefore we must understand how this gene spreads in the environment.”If we can stem the spread of such antibiotic resistant genes locally — possibly through improved sanitation and waste treatment — we have a better chance of limiting their spread on larger scales, creating global solutions by solving local problems.”Funded by the Engineering and Physical Sciences Research Council (EPSRC), the aim of the research was to understand how antibiotic resistance was transmitted due to a specific human activity. Local “hot-spots” of antibiotic resistance exist around the world, particularly densely-populated regions with inconsistent sanitation and poor water quality.By comparing water quality of the Upper Ganges in February and again in June, the team showed that levels of blaNDM-1 were 20 times higher per capita during the pilgrimage season than at other times.Monitoring levels of other contaminants in the water, the team showed that overloading of waste treatment facilities was likely to blame and that in many cases, untreated sewage was going straight into the river where the pilgrims bathe.”The bugs and their genes are carried in people’s guts,” explains Professor Graham. “If untreated wastes get into the water supply, resistance potential in the wastes can pass to the next person and spiralling increases in resistance can occur.”Worldwide, concern is growing over the threat from bacteria that are resistant to the so-called “last resort” class of antibiotics known as Carbapenems, especially if resistance is acquired by aggressive pathogens.Of particular concern is NDM-1, which is a protein that confers resistance in a range of bacteria. NDM-1 was first identified in New Delhi and coded by the resistant gene blaNDM-1.Until recently, strains that carry blaNDM-1 were only found in clinical settings, but in 2008, blaNDM-1 positive strains were found in surface waters in Delhi. Since then, blaNDM-1 has been found elsewhere in the world, including new variants.There are currently few antibiotics to combat bacteria that are resistant to Carbapenems and worldwide spread of blaNDM-1 is a growing concern.Professor Graham, who is based in the School of Civil Engineering and Geosciences at Newcastle University, UK, said the team had planned to repeat their experiments last year, but the region was hit by massive floods in June and the experiments were abandoned.The team has since returned to Rishikesh and Haridwar and hope their work will prompt public action to improve local sanitation, protecting these socially important sites. On a global scale, they want policymakers to recognise the importance of clean drinking water in our fight against antibiotic resistance.”What humans have done by excess use of antibiotics is accelerate the rate of evolution, creating a world of resistant strains that never existed before” explains Graham.”Through the overuse of antibiotics, contamination of drinking water and other factors, we have exponentially speeded-up the rate at which superbugs might develop.”For example, when a new drug is developed, natural bacteria can rapidly adapt and become resistant; therefore very few new drugs are in the pipeline because it simply isn’t cost-effective to make them.”The only way we are going to win this fight is to understand all of the pathways that lead to antibiotic resistance. Clearly, improved antibiotic stewardship in medicine and agriculture is crucial, but understanding how resistance transmission occurs through our water supplies is also critical. We contend that improved waste management and water quality on a global scale is a key step.”


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#Cancer, #Environmental, #Gene, #Graham, #King, #Newcastleuniversity, #Professor, #River

Fertilization destabilizes global grassland ecosystems

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A new study led by University of Minnesota researchers demonstrates that fertilization of natural grasslands — either intentionally or unintentionally as a side effect of global farming and industry — is having a destabilizing effect on global grassland ecosystems. Using a network of natural grassland research sites around the world called the Nutrient Network, the study represents the first time such a large experiment has been conducted using naturally occurring sites.Led by Yann Hautier, a Marie Curie Fellow associated with both the Department of Ecology, Evolution, and Behavior at the University of Minnesota and the Institute of Evolutionary Biology and Environmental Studies at the University of Zurich, the research team included U of M associate professors Eric Seabloom and Elizabeth Borer, and research scientist Eric Lind, along with scientists from institutions around the world including Andy Hector at Oxford University’s Department of Plant Sciences. The findings were published on February 16 in the journal Nature.The researchers found that plant diversity in natural ecosystems creates more stable ecosystems over time because of less synchronized growth of plants. “This is sometimes called the portfolio effect,” says Seabloom. “If you have money in two investments and they’re both stocks, they’re going to track each other, but if one is a stock and one is a bond, they’re going to respond differently to the overall economy and are more likely to balance each other.”The researchers collected plants from each of the sites, then sorted, dried, and weighed them to monitor the number of species of plants and total amount of plants, or “biomass,” grown over time. They used this information to quantify species diversity and ecosystem stability. Says Hautier: “It was really striking to see the relationship between diversity and stability” and the similarities to data collected from artificial grasslands as part of a research effort called BioDepth, indicating that the results from natural grasslands of the Nutrient Network could be predicted from the results of artificial grasslands.”The results of our study emphasize that we need to consider not just how productive ecosystems are but also how stable they are in the long-term, and how biodiversity is related to both aspects of ecosystem functioning,” says Andy Hector.The researchers also found that grassland diversity and stability are reduced when fertilizer is added. Fertilizers are intentionally used in grassland to increase livestock fodder. Fertilizer addition is also occurring unintentionally in many places around the world because nitrogen, a common fertilizer, is released into the atmosphere from farming, industry, and burning fossil fuels. Rainfall brings nitrogen out of the atmosphere and on to grasslands, changing the growth and types of plant species. …


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Environmental impact of Ontario corn production assessed

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Researchers at the University of Guelph examined the energy use and greenhouse gas (GHG) emissions associated with corn production in Ontario. Their findings are published today in the Agricultural Institute of Canada’s (AIC) Canadian Journal of Soil Science.The study reports estimated county-level energy and GHG intensity of grain corn, stover and cob production in Ontario from 2006-2011. According to the paper’s authors, most of the energy used during corn production comes from the use of natural gas and electricity during grain drying; the production and application of nitrogen fertilizers (which are also associated with GHG emissions); and the use of diesel fuel during field work.”Corn is a major economic crop in North America, and the renewable fuels developed from corn production are frequently used to mitigate the GHG emissions from fossil fuel use,” explained Susantha Jayasundara, lead author of the paper.”Assessing the GHG and energy intensity of corn production helps identify opportunities for efficiency and aids in improving the GHG mitigation potential of corn-derived renewable fuels,” continued Jayasundara. The authors note that reducing GHG intensity and improving energy efficiency during corn production can be achieved through the use of field-drying corn hybrids, reduced tillage and diminished nitrogen inputs.The article, “Energy and Greenhouse Gas Intensity of Corn (Zea Mays L.) in Ontario: A regional assessment,” by Susantha Jayasundara, Claudia Wagner-Riddle, Goretty Dias and Kumudinie Kariyapperuma, is available Open Access in the Canadian Journal of Soil Science.”Given the environmental and economic benefits of renewable fuels and the proliferation of their use in Canada, it is important to more fully understand the environmental impacts of their associated agricultural production,” added Serge Buy, CEO of AIC. “Essential studies such as this are of national significance and are certainly evidence of the need for targeted federal investments in agricultural science.”Story Source:The above story is based on materials provided by Canadian Science Publishing (NRC Research Press). Note: Materials may be edited for content and length.


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#Alzheimer, #Canadian, #Environmental, #Health, #Journal, #Major, #North, #Production

Air pollution increases risk for hypertension in pregnant women

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Breathing the air outside their homes may be just as toxic to pregnant women — if not more so — as breathing in cigarette smoke, increasing a mom-to-be’s risk of developing deadly complications such as preeclampsia, according to findings from a new University of Florida study.UF researchers compared birth data with Environmental Protection Agency estimates of air pollution, finding that heavy exposure to four air pollutants led to a significantly increased risk for developing a high blood pressure disorder during pregnancy. The research was published in the January issue of the Journal of Epidemiology & Community Health.The pollutants include two specific types of fine and coarse particulate matter, carbon monoxide and sulfur dioxide. According to the EPA, particulate matter includes acids, dust, metals and soil particles. These inhalable particles are released from industries and forest fires and can form when gases react with each other in the air. Sulfur dioxide is emitted from power plants and industries. Most carbon monoxide is produced by car exhaust.”Fetal development is very sensitive to environmental factors,” said Xiaohui Xu, M.D., Ph.D., an assistant professor of epidemiology in the colleges of Public Health and Health Professions and Medicine. “That is why we wanted to do this research. Hypertension (high blood pressure), in particular, is associated with increased morbidity and mortality, causing a lot of problems for the mother and fetus, including preterm delivery.”Hypertensive disorders such as gestational hypertension, preeclampsia and the deadly condition it leads to, eclampsia, affect about 10 percent of pregnancies. Despite the serious risks to mother and baby, little is known about what specifically causes these conditions to develop in pregnant women, the researchers say.To gain a better understanding of how environmental factors may play a role in increasing the risk of developing hypertension during pregnancy, the researchers examined data from women who gave birth in Jacksonville, Fla., between 2004 and 2005 and environmental data from their communities. The sample included more than 22,000 pregnant women.The researchers did not include mothers with chronic hypertension, those who had previously given birth prematurely or those whose babies were born with other complications in the sample. …


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#Colleges, #Ecology, #Environmental, #Epa, #Epidemiology, #Health, #Homes, #Science, #Story

Madagascar sells first forest carbon credits to Microsoft

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The Government of Madagascar has approved carbon sales with Microsoft and its carbon offset partner, The CarbonNeutral Company, and Zoo Zurich. The carbon credit sales will support the Government of Madagascar’s REDD+ Project (Reducing Emissions from Deforestation and Forest Degradation “plus” conservation) in the Makira Natural Park and mark the first sale of government-owned REDD+ credits in Africa.Through carbon credit sales from avoided deforestation, the Makira REDD+ Project will finance the long-term conservation of one of Madagascar’s most pristine remaining rainforest ecosystems harboring rare and threatened plants and animals while improving community land stewardship and supporting the livelihoods of the local people.Through a unique funding distribution mechanism designed by WCS and the Government of Madagascar, the funds from carbon sales will be used by the Government of Madagascar for conservation, capacity building, and enforcement activities, and by WCS to manage the Makira Natural Park. The largest share of the sale — half of the proceeds — will go to supporting local communities in the areas surrounding Makira for education, human health and other beneficial projects.”The Government of Madagascar is thrilled to have played the role of pioneer in carbon sales in Africa. Makira is a highly valued part of our natural heritage and the revenues from this sale will not only protect this oustanding area, but represent an important step in our plan to develop sustainable sources of financing for the whole protected area network. We hope that other organizations will follow the lead of Microsoft, The CarbonNeutral Company, and Zoo Zurich and join us in this effort to conserve Madagascar’s unique biodiversity through the sale of future carbon credits,” said Pierre Manganirina Randrianarisoa the Secretary General of the Ministry of Environment and Forests.Said WCS President and CEO Cristin Samper “These sales represent a first for WCS, a first for Africa, and a first for Madagascar in advancing the use of carbon credits to fight climate change while protecting biodiversity and human livelihoods. We are thankful to Microsoft, The CarbonNeutral Company and Zoo Zurich, and we look forward to future purchases by other forward-thinking organizations.”Said Rob Bernard, Chief Environmental Strategist at Microsoft: “Supporting forest conservation and community building projects like Makira is an important part of Microsoft’s strategy to reduce its environmental impact, support sustainable economic growth, improve health and education, and address societal challenges. The project’s important role in protecting a crucial area of biodiversity value also aligns with Microsoft’s own focus on using technology, information and research to develop new approaches and solutions to sustainability.”Said Jonathan Shopley, Managing Director of The CarbonNeutral Company: “Increasingly our clients are looking for opportunities to manage the entire environmental impact of their organisation, driven by the need to build resilience in their supply chains. The Makira project enables clients to do this by selling carbon credits while also delivering biodiversity value and community support.”Makira contains an estimated one percent of the world’s biodiversity including 20 lemur species, hundreds of species of birds, and thousands of plant varieties, including many found nowhere else on earth. The Makira forest spans nearly 400,000 hectares (more than 1,500 square miles), making it one of the largest remaining intact blocks of rainforest in Madagascar. In addition, Makira’s forests serve as a zone of watershed protection, providing clean water to over 250,000 people in the surrounding landscape.WCS, which has worked in Makira since 2003, is the delegated manager of the park and is responsible for implementing the REDD+ project that aims to safeguard the Makira Natural Park, one of Madagascar’s largest protected areas.Last September the Government of Madagascar and WCS announced that 710,588 carbon credits had been certified for sale from the Makira Forest REDD+ Project. …


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#Africa, #Alternative-Medicine, #Cancer, #Chief, #Environmental, #Government, #Health, #Madagascar, #Microsoft, #President, #Redd, #Wcs

Change in guidelines for type 2 diabetes screening tests may lead to under-diagnosis in children

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New American Diabetes Association (ADA) screening guidelines may lead to the missed diagnoses of type 2 diabetes in children, according to a new study by University of Michigan.The research, published in the Journal of Adolescent Health, finds that both pediatric and family medicine providers who care for children are using screening tests for type 2 diabetes that may result in missed diagnoses for children, says lead author Joyce Lee, M.D., M.P.H., associate professor in U-M’s Departments of Pediatrics and Communicable Diseases and Environmental Health Sciences.In 2010, the ADA recommended that physicians use Hemoglobin A1c screening tests, rather than glucose tests for identifying children and adults with pre-diabetes and diabetes. However, this change has been controversial, because of lower test performance of HbA1c in children compared with adults.The study found that when presented with the ADA screening guidelines, 84% of physicians reported that they would switch from using glucose tests to using HbA1c tests.”This potential for increased uptake of HbA1c could lead to missed cases prediabetes and diabetes in children, and increased costs,” says Lee.”A number of studies have shown that HbA1c has lower test performance in pediatric compared with adult populations, and as a result, increased uptake of HbA1c alone or in combination with non-fasting tests could lead to missed diagnoses of type 2 diabetes in the pediatric population.’”Also, a recent analysis of screening strategies found that HbA1c is much less cost-effective than other screening tests, which would result in higher overall costs for screening.”The study was based on a national sample of providers from pediatrics and family practice.”Greater awareness of the 2010 ADA guidelines will likely lead to increased uptake of HbA1c and a shift to use of non-fasting tests to screen for adolescents with type 2 diabetes. This may have implications for detection rates for diabetes and overall costs of screening.”Story Source:The above story is based on materials provided by University of Michigan Health System. Note: Materials may be edited for content and length.


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Plastic shopping bags make a fine diesel fuel

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Plastic shopping bags, an abundant source of litter on land and at sea, can be converted into diesel, natural gas and other useful petroleum products, researchers report.The conversion produces significantly more energy than it requires and results in transportation fuels — diesel, for example — that can be blended with existing ultra-low-sulfur diesels and biodiesels. Other products, such as natural gas, naphtha (a solvent), gasoline, waxes and lubricating oils such as engine oil and hydraulic oil also can be obtained from shopping bags.A report of the new study appears in the journal Fuel Processing Technology.There are other advantages to the approach, which involves heating the bags in an oxygen-free chamber, a process called pyrolysis, said Brajendra Kumar Sharma, a senior research scientist at the Illinois Sustainable Technology Center who led the research. The ISTC is a division of the Prairie Research Institute at the University of Illinois.”You can get only 50 to 55 percent fuel from the distillation of petroleum crude oil,” Sharma said. “But since this plastic is made from petroleum in the first place, we can recover almost 80 percent fuel from it through distillation.”Americans throw away about 100 billion plastic shopping bags each year, according to the Worldwatch Institute. The U.S. Environmental Protection Agency reports that only about 13 percent are recycled. The rest of the bags end up in landfills or escape to the wild, blowing across the landscape and entering waterways.Plastic bags make up a sizeable portion of the plastic debris in giant ocean garbage patches that are killing wildlife and littering beaches. Plastic bags “have been detected as far north and south as the poles,” the researchers wrote.”Over a period of time, this material starts breaking into tiny pieces, and is ingested along with plankton by aquatic animals,” Sharma said. Fish, birds, ocean mammals and other creatures have been found with a lot of plastic particles in their guts.Whole shopping bags also threaten wildlife, Sharma said.”Turtles, for example, think that the plastic grocery bags are jellyfish and they try to eat them,” he said. Other creatures become entangled in the bags.Previous studies have used pyrolysis to convert plastic bags into crude oil. …


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Solving an evolutionary puzzle: Atlantic killifish thriving in highly polluted water

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For four decades, waste from nearby manufacturing plants flowed into the waters of New Bedford Harbor — an 18,000-acre estuary and busy seaport. The harbor, which is contaminated with polychlorinated biphenyls (PCBs) and heavy metals, is one of the EPA’s largest Superfund cleanup sites.It’s also the site of an evolutionary puzzle that researchers at Woods Hole Oceanographic Institution (WHOI) and their colleagues have been working to solve.Atlantic killifish — common estuarine fishes about three inches long — are not only tolerating the toxic conditions in the harbor, they seem to be thriving there. How have they been able to adapt and live in such a highly contaminated environment?In a new paper published in BMC Evolutionary Biology, researchers found that changes in a receptor protein, called the aryl hydrocarbon receptor 2 (AHR2), may explain how killifish in New Bedford Harbor evolved genetic resistance to PCBs.Killifish are prey fish that do not migrate. They live their whole lives in the same area, generally within a few hundred yards of the spot where they were hatched. Unlike fish that may come in and out of the harbor sporadically during the summer months to feed, the killifish are there year round and spend winters burrowing into the contaminated sediment.Normally when fish are exposed to harmful chemicals, the body steps up production of enzymes that break down the pollutants, a process controlled by the AHR2 protein. Some of the PCBs are not broken down in this way, and their continued stimulation of AHR2 disrupts cellular functions, leading to toxicity. In the New Bedford Harbor killifish, the AHR2 system has become resistant to this effect.”The killifish have managed to shut down the pathway,” said Mark Hahn, a biologist at WHOI and coauthor of the paper. “It’s an example of how some populations are able to adapt to changes in their environment — a snapshot of evolution at work.”The research team, which includes colleagues from the Atlantic Ecology Division of the U.S. Environmental Protection Agency, the Boston University School of Public Health, and the University of North Carolina at Charlotte, used a “candidate gene” approach, sequencing the protein-coding portion of three candidate resistance genes (AHR1, AHR2, AHRR) in fish from the New Bedford site and six other locations, both clean and polluted, along the northeast coast.Looking for single nucleotide polymorphisms (SNPs) or subtle variations in the DNA sequence, they found differences in AHR2, which plays an important role in mediating toxicity in early life stages.”The function of this receptor is what mediates the toxic effects,” said Sibel Karchner, a coauthor and biologist in Hahn’s lab. “If you don’t have a functional receptor, then you’re not going to get the toxic effects as much as a fish that does.”AHR2 in killifish has 951 amino acids and nine of those vary among individuals. …


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#Agriculture, #Bedfordharbor, #Environmental, #Major, #National, #Professor, #River, #Science