Vulnerability of sharks as collateral damage in commercial fishing shown by study

A new study that examined the survival rates of 12 different shark species when captured as unintentional bycatch in commercial longline fishing operations found large differences in survival rates across the 12 species, with bigeye thresher, dusky, and scalloped hammerhead being the most vulnerable. The study, led by researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science and UM Abess Center for Ecosystem Science and Policy, provides new information to consider for future conservation measures for sharks in the Northwest Atlantic. The unintentional capture of a fish species when targeting another species, known as bycatch, is one of the largest threats facing many marine fish populations.Researchers from UM and the National Marine Fisheries Service analyzed over 10 years of shark bycatch data from the western Atlantic Ocean and Gulf of Mexico tuna and swordfish longline fisheries to examine how survival rates of sharks were affected by fishing duration, hook depth, sea temperature, animal size and the target fish. Some species, such as the tiger shark, exhibited over 95% survival, whereas other species survival was significantly lower, in the 20-40% range, such as night shark and scalloped hammerheads.”Our study found that the differences in how longline fishing is actually conducted, such as the depth, duration, and time-of-day that the longlines are fished can be a major driver of shark survival, depending on the species,” said UM Rosenstiel School Ph.D student and lead author Austin Gallagher. “At-vessel mortality is a crucial piece of the puzzle in terms of assessing the vulnerability of these open-ocean populations, some of which are highly threatened.”The researchers also generated overall vulnerability rankings of species taking into account not only their survival, but also reproductive potential. They found that species most at risk were those with both very slow reproductive potential and unusual body features, such as hammerheads and thresher sharks. The paper’s authors suggest that bycatch likely played an important role in the decline of scalloped hammerhead species in the Northwest Atlantic, which has been considered for increased international and national protections, such as the U.S. Endangered Species List.The researchers suggest that high at-vessel mortality, slow maturity, and specialized body structures combine for the perfect mixture to become extinction-prone.”Our results suggest that some shark species are being fished beyond their ability to replace themselves,” said UM Research Assistant Professor Neil Hammerschlag. “Certain sharks, such as big eye threshers and scalloped hammerheads, are prone to rapidly dying on the line once caught and techniques that reduce their interactions with fishing gear in the first place may be the best strategy for conserving these species.”The study, titled “Vulnerability of oceanic sharks as pelagic longline bycatch” was published online in the open-access journal Global Ecology and Conservation.Story Source:The above story is based on materials provided by University of Miami Rosenstiel School of Marine & Atmospheric Science. Note: Materials may be edited for content and length.

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Land cover change over five years across North America revealed

A new set of maps featured in the CEC’s North American Environmental Atlas depicts land cover changes in North America’s forests, prairies, deserts and cities, using satellite images from 2005 and 2010. These changes can be attributed to forest fires, insect infestation, urban sprawl and other natural or human-caused events. Produced by the North American Land Change Monitoring System (NALCMS), a trinational collaborative effort facilitated by the CEC, these maps and accompanying data can be used to address issues such as climate change, carbon sequestration, biodiversity loss, and changes in ecosystem structure and function.This project, which seeks to address land cover change at a North American scale, was initiated at the 2006 Land Cover Summit, in Washington, DC. Since then, specialists from government agencies in Canada, Mexico and the United States have worked together to harmonize their land cover classification systems into 19 classes that provide a uniform view of the continent at a consistent 250-meter scale.To view examples of significant land cover changes in British Colombia, California, and Cancun, slide the green bars on the maps, found at: www.cec.org/nalcms.To view the full 2005-2010 land cover change map, visit www.cec.org/atlas and click on “Terrestrial Ecosystems” on the left. Under “Land Cover,” click on the plus sign next to “2005-2010 land cover change” to add the map layer to North America. Then zoom in and take a look at all the purple patches — these are the areas of North America where land cover has changed over the five-year period.North American Land Change Monitoring SystemNALCMS is a joint project between Natural Resources Canada/Canada Centre for Mapping and Earth Observation (NRCan/CCMEO), the United States Geological Survey (USGS), and three Mexican organizations: the National Institute of Statistics and Geography (Instituto Nacional de Estadstica y Geografa — Inegi), the National Commission for the Knowledge and Use of Biodiversity (Comisin Nacional para el Conocimiento y Uso de la Biodiversidad — Conabio), and the National Forestry Commission of Mexico (Comisin Nacional Forestal — Conafor), supported by the Commission for Environmental Cooperation (CEC).The North American Environmental AtlasThe North American Environmental Atlas brings together maps, data and interactive map layers that can be used to identify priority areas to conserve biodiversity, track cross-border transfers of pollutants, monitor CO2 emissions across major transportation routes and predict the spread of invasive species. Land Cover 2010 and Land Cover Change 2005-2010 are the latest in a series of maps that harmonize geographic information across North America’s political boundaries to depict significant environmental issues at a continental scale.Story Source:The above story is based on materials provided by Commission for Environmental Cooperation. Note: Materials may be edited for content and length.

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Sterile flies save food crops, millions of dollars in eradication efforts

Irradiated, sterile flies dropped over seaports and agricultural areas to mate with unsuspecting females save food crops and millions of dollars in prevented infestations and the ensuing eradication efforts. But blasting these secret-suitor insects with radiation via electron beams, X-rays or gamma-rays, tends to make them weaker than typical males — and not so appealing to females as possible mates.What sterile-insect operations need, says University of Florida insect physiologist Daniel Hahn, is the insect world’s version of George Clooney: 52 years old, gray-haired and still dazzling the ladies.Hahn, an associate professor with UF’s Institute of Food and Agricultural Sciences, and his former postdoctoral associate, Giancarlo Lpez-Martnez, now an assistant professor at New Mexico State University, describe in research publications this month and last, that sterilizing insects in a low-oxygen environment helps create suitors who more closely resemble the suave Clooney than do those sterilized in a normal-oxygen environment.”Our males (insects) are not only more sexually competitive, they are maintaining their sexual competitiveness and their virility, into old age,” Hahn said, “and that has the potential to make them much better biological control agents.”The sterile insect technique, or SIT, has been used for decades and is considered a much preferable alternative to spraying pesticides over urban or suburban areas near major ports. In this biological control method, large numbers of sterile, male insects are released to compete with wild males for the attention of invasive wild females.A female duped into accepting a sterile male would then find herself without offspring, thus trimming the population and its threat to the state’s important agricultural crops. The technique has been used effectively against the Mediterranean fruit fly, called the Medfly, and the cattle-infesting screw-worm fly, among others.Florida spends roughly $6 million a year using SIT to prevent Mediterranean fruit fly infestations, while California spends about $17 million a year. Because of the inherent dangers in importing even one Mediterranean fruit fly into the state, in their recent studies, Lpez-Martnez and Hahn investigated the physiological effects of applying low-oxygen treatments prior to and during irradiation sterilization on two other plant pests: the Caribbean fruit fly and the invasive cactus moth.The “low-oxygen effect” has been known for decades, but the physiological basis for it had never been rigorously tested or analyzed, Hahn said. They suspected, and found, that under the low-oxygen conditions, the insects’ cells would produce antioxidants that can help better protect them from the off-target radiation damage.Some operations that rear and sterilize insects, such as one in Guatemala that produces many of the sterile medflies dropped over Florida’s major ports roughly every seven days, do employ low-oxygen conditions, called hypoxia or anoxia. But many others don’t, he said, including those who rear and sterilize the cactus moth.The reseachers found using a low-oxygen environment during sterilization boosted the sterile males’ longevity as well as their ability to attract and successfully mate. They found that the positive effects of low-oxygen treatments even extended into their ‘old age’ — in the insects’ case, about 30 days under cushy laboratory conditions.Treatments that both improve the sexual performance of sterile males and maintain high performance longer in older males can substantially increase the effectiveness and decrease the economic costs of SIT programs, Hahn said.The January paper was published by PLoS One, and the February paper in the Journal of Economic Entomology. Hahn and Lpez-Martnez were joined as authors of that paper by James Carpenter of the USDA’s Agricultural Research Service in Tifton, Ga., and Stephen Hight of the USDA-ARS at Florida A&M University in Tallahassee.

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Legal harvest of marine turtles tops 42,000 each year

A new study has found that 42 countries or territories around the world permit the harvest of marine turtles — and estimates that more than 42,000 turtles are caught each year by these fisheries.The research, carried out by Blue Ventures Conservation and staff at the University of Exeter’s Centre for Ecology and Conservation, is the first to comprehensively review the number of turtles currently taken within the law and assess how this compares to other global threats to the creatures.All seven marine turtle species are currently listed on the IUCN Red List of Threatened Species.Frances Humber of Blue Ventures and a PhD student at the University of Exeter, who led the research, said: “This is the first study to comprehensively review the legal take of turtles in recent years, and allows us to assess the relative fisheries threats to this group of species. Despite increased national and international protection of marine turtles, direct legal take remains a major source of mortality. However, it is likely that a fraction of current marine turtle mortality take is legal, with greater threats from illegal fisheries and bycatch.”The first marine turtle harvest legislation was instigated in Bermuda in 1620 to protect “so excellent a fishe” and prohibited taking any turtle “under eighteen inches in the breadth or diameter.”But large scale commercial taking of turtles continued all over the world for centuries, with global capture peaking at over 17,000 tonnes in the late 1960s. For example, during the peak of Mexico’s sea turtle exploitation in 1968 it is estimated that the national take was over 380,000 turtles.Increased conservation awareness at an international scale has led to greater protection of marine turtles, with 178 countries now signed up to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) restricting the international trade of turtle products.The direct take of turtles has continued legally in many regions and countries, often for traditional coastal communities to support themselves or small-scale fisheries supplying local markets with meat, and sometimes shell. The fisheries are an important source of finance, protein and cultural identity, but information can be scarce on their status — despite often being listed as one of the major threats to turtle populations.The researchers collated data for all seven species of marine turtles from over 500 publications and 150 in-country experts.They estimate that currently more than 42,000 marine turtles are caught each year legally, of which over 80% are green turtles. Legal fisheries are concentrated in the wider Caribbean region, including several of the UKs Overseas Territories, and the Indo-Pacific region, with Papua New Guinea, Nicaragua and Australia together accounting for almost three quarters of the total.The data indicates that since the 1980s more than 2 million turtles have been caught, although current levels are less than 60% of those in the 1980s.Bycatch — the unwanted fish and other marine creatures trapped by commercial fishing nets during fishing for a different species — is thought to be a far higher cause of death for marine turtles, likely running into hundreds of thousands each year.Illegal fishing also continues to be a major cause of mortality, with the researchers estimating a minimum of 65,000 turtles taken from Mexico alone since the year 2000. The scale of global illegal capture is likely to be severely underreported due to the difficulties collecting information on such an activity.Dr Annette Broderick, of the Centre for Ecology and Conservation at the University of Exeter’s Penryn Campus in Cornwall, added: “We were surprised to find that there are 42 countries with no legislation in place that prohibits the harvest of marine turtles, although for many of these countries these harvests provide important sources of protein or income. It is however important to ensure that these fisheries are operating at a sustainable level.”Story Source:The above story is based on materials provided by University of Exeter. Note: Materials may be edited for content and length.

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Heavy air pollution in Canadian area with cancer spikes

Oct. 22, 2013 — Levels of contaminants higher than in some of the world’s most polluted cities have been found downwind of Canada’s largest oil, gas and tar sands processing zone, in a rural area where men suffer elevated rates of cancers linked to such chemicals.The findings by UC Irvine and University of Michigan scientists, published online this week, reveal high levels of the carcinogens 1,3-butadiene and benzene and other airborne pollutants. The researchers also obtained health records spanning more than a decade that showed the number of men with leukemia and non-Hodgkin’s lymphoma was greater in communities closest to the pollution plumes than in neighboring counties. The work is a dramatic illustration of a new World Health Organization report that outdoor air pollution is a leading cause of cancer.While the scientists stopped short of saying that the pollutants they documented were definitely causing the male cancers, they strongly recommended that the industrial emissions be decreased to protect both workers and nearby residents.”Our study was designed to test what kinds of concentrations could be encountered on the ground during a random visit downwind of various facilities. We’re seeing elevated levels of carcinogens and other gases in the same area where we’re seeing excess cancers known to be caused by these chemicals,” said UC Irvine chemist Isobel Simpson, lead author of the paper in Atmospheric Environment. “Our main point is that it would be good to proactively lower these emissions of known carcinogens. You can study it and study it, but at some point you just have to say, ‘Let’s reduce it.’ “Co-author Stuart Batterman, a University of Michigan professor of environmental health sciences, agreed: “These levels, found over a broad area, are clearly associated with industrial emissions. They also are evidence of major regulatory gaps in monitoring and controlling such emissions and in public health surveillance.”The researchers captured emissions in the rural Fort Saskatchewan area downwind of major refineries, chemical manufacturers and tar sands processors owned by BP, Dow, Shell and other companies in the so-called “Industrial Heartland” of Alberta. They took one-minute samples at random times in 2008, 2010 and 2012. All showed similar results. …

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Rats! Humans and rodents process their mistakes

Oct. 20, 2013 — What happens when the brain recognizes an error? A new study shows that the brains of humans and rats adapt in a similar way to errors by using low-frequency brainwaves in the medial frontal cortex to synchronize neurons in the motor cortex. The finding could be important in studies of “adaptive control” like obsessive compulsive disorder, ADHD, and Parkinson’s.People and rats may think alike when they’ve made a mistake and are trying to adjust their thinking.That’s the conclusion of a study published online Oct. 20 in Nature Neuroscience that tracked specific similarities in how human and rodent subjects adapted to errors as they performed a simple time estimation task. When members of either species made a mistake in the trials, electrode recordings showed that they employed low-frequency brainwaves in the medial frontal cortex (MFC) of the brain to synchronize neurons in their motor cortex. That action correlated with subsequent performance improvements on the task.”These findings suggest that neuronal activity in the MFC encodes information that is involved in monitoring performance and could influence the control of response adjustments by the motor cortex,” wrote the authors, who performed the research at Brown University and Yale University.The importance of the findings extends beyond a basic understanding of cognition, because they suggest that rat models could be a useful analog for humans in studies of how such “adaptive control” neural mechanics are compromised in psychiatric diseases.”With this rat model of adaptive control, we are now able to examine whether novel drugs or other treatment procedures boost the integrity of this system,” said James Cavanagh, co-lead author of the paper who was at Brown when the research was done and has since become assistant professor of psychology at the University of New Mexico. “This may have clear translational potential for treating psychiatric diseases such as obsessive compulsive disorder, depression, attention deficit hyperactivity disorder, Parkinson’s disease and schizophrenia.”To conduct the study, the researchers measured external brainwaves of human and rodent subjects after both erroneous and accurate performance on the time estimation task. They also measured the activity of individual neurons in the MFC and motor cortex of the rats in both post-error and post-correct circumstances.The scientists also gave the rats a drug that blocked activity of the MFC. What they saw in those rats compared to rats who didn’t get the drug, was that the low-frequency waves did not occur in the motor cortex, neurons there did not fire coherently and the rats did not alter their subsequent behavior on the task.Although the researchers were able to study the cognitive mechanisms in the rats in more detail than in humans, the direct parallels they saw in the neural mechanics of adaptive control were significant.”Low-frequency oscillations facilitate synchronization among brain networks for representing and exerting adaptive control, including top-down regulation of behavior in the mammalian brain,” they wrote.In addition to Cavanagh, the lead authors are Nandakumar Narayanan, formerly of Yale and now of the University of Iowa, and James Cavanagh, formerly of Brown and now of the University of New Mexico. …

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The Greatest Escape Motorcycle Ride

Worthington & Caron, PC in association with Bartels’ Harley-Davidson and Pacific Meso Center is proud to present The Greatest Escape, a memorial motorcycle ride to celebrate the 50th anniversary ofThe Great Escapemovie starring Steve McQueen, whose life was cut short at the age of 50 on November 7, 1980 by malignant peritoneal mesothelioma.McQueen’s story is well known. After his diagnosis in Los Angeles in 1979, McQueen eschewed conventional therapies for untested nostrums in Mexico, such as laetrile, coffee enemas and cow fetus injections. The Hollywood icon died soon after in 1980.Join us Sunday, September 22, 2013 for a beautiful scenic ride on coastal Pacific Coast Highway beginning at Bartels’ Harley-Davidson in Marina Del Rey up to Sycamore Cove State Beach. The ride will be followed by a delicious tri-tip …

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World’s first mapping of America’s rare plants

Oct. 17, 2013 — In collaboration with international colleagues, a research group at Aarhus University has contributed to the compilation of the most comprehensive botanical data set to date. PhD student Naia Morueta-Holme and her supervisor, Professor Jens-Christian Svenning, Department of Bioscience, spearheaded the analysis that reveals where rare species are found in the New World (North and South America) and the factors that determine whether a region is dominated by widespread or rare species.”The study shows that especially California, Mexico, the Caribbean islands, parts of the Andes, the south of South America, and the region around Rio de Janeiro are dominated by rare species. This came as a surprise to us, because the regions are very different in terms of climate and vegetation type. They include habitats such as wet tropical rainforests, dry subtropical regions, and even deserts, tropical mountains, and cool temperate grasslands and forests,” says Professor Svenning.However, the studies show that consistent processes are driving the distribution of the plants.”There are two factors in particular that are important for the distribution of the rare species. Firstly, a stable climate with relatively small seasonal differences, where the climate has remained much the same for tens of thousands of years. Secondly, only small areas of habitat are involved. The species are unable to spread, but the stability nevertheless enables them to survive for long periods of time, and to develop and specialise in the same place,” explains Naia Morueta-Holme.In large areas in the north of North America, on the other hand, the seasons vary significantly, and there have been distinct climate changes between ice ages (glacials) and warm ages (interglacials). Widespread species are dominant here, either because they can withstand a wide range of climate conditions or because they are good at dispersing and can track changes in climate over time. They can thus spread over the large habitat areas available.Rare species threatened by climate changeIn terms of the dominance of rare species, the close link between the size of the habitat area and a stable climate is of great concern regarding the impact of human-induced climate changes now prevailing in these regions.”Even though we’re expecting less climate change in the areas dominated by rare species than in North America, for example, it could well be that future changes may be beyond what the species can tolerate. …

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Flower research shows gardens can be a feast for the eyes – and the bees

Oct. 16, 2013 — Are our favourite garden flowers attractive to hungry visitors such as bees and butterflies to feed on?Researchers at the Laboratory of Apiculture and Social Insects (LASI) at the University of Sussex have completed one of the first scientific studies to put the business of recommending pollinator-friendly garden flowers on a firmer scientific footing. The study’s findings are published today (17 October 2013) in the journalFunctional Ecology.Gardens are more important than ever as a source of food for a wide variety of insects who feed on the nectar and pollen found in many flowers: pollinators such as bees and butterflies are in decline globally, with one of the main causes being the loss of flowers, especially in the countryside.As popular support for wildlife continues to grow, gardeners are increasingly looking for ways to help bees and other insects by providing attractive flowers in their gardens for insects to feed on. To do this, they often rely on “pollinator-friendly” plant lists. But these lists are generally based on opinion and experience rather than scientific research.The study, funded by the Body Shop Foundation, involved repeatedly counting flower-visiting insects over two summers as they foraged on 32 popular summer-flowering garden plant varieties in a specially planted experimental garden on the University’s campus (each variety in 2 1x1m beds), with two smaller additional gardens set up in year two to check the generality of the results.Plant varieties studied included 19 species and hybrids, both native and exotic to Britain, with particular focus on 13 varieties of lavender (Lavandula spp.), as it is known to be attractive to bees, and also four dahlias. All the plants studied had to be popular garden plants, be widely and easily available for purchase, and had to flower mainly or exclusively in July/August.2One key result found by researchers Professor Francis Ratnieks and his PhD student Mihail Gaburzov was that garden flowers attractive to the human eye vary enormously (approx 100-fold) in their attractiveness to insects, meaning that the best plants for bees and other insects are 100 times better than the worst. So it pays to make an informed choice of plants from the thousands available to gardeners.Bees (87 per cent) and hoverflies (nine per cent) were the most frequent visitors, with butterflies and moths just two per cent and all other insects also two per cent. The researchers observed clear differences in the mix of bee and insect types attracted by different varieties, indicating that careful plant choice can not only help insects in general, but also help a range of insects.Other findings were:Some cultivated varieties and non-native flowers – usually seen as ornamental only – can be helpful to wildlife. For example, open dahlias attracted many bees, especially bumblebees, but pom-pom or cactus dahlias attracted few insects, because their highly-bred flowers make it difficult for insects to reach the flowers’ pollen and nectar. Highly bred varieties of lavender, including those of novel colours, such as white or pink, or hybrid lavenders, proved highly attractive to insects. …

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Action-inaction balance in cultural values more common in East Asian countries

Sep. 3, 2013 — People in East Asian countries seem to strike the best balance between liking action and inaction, whereas someone from the Mediterranean area of the world are far less likely to have achieved the same balance.This balance between action and inaction is best displayed in Asia, where Labor Day is not observed until May.A two-year-long study involving over 4,000 volunteer participants (age 19 to 30) from 19 countries and looked at the degree to which a culture holds attitudes toward rest and activity. It was led by Dolores Albarracín, Ph.D., the Martin Fishbein Chair at the Annenberg School for Communication and Professor of Psychology at the University of Pennsylvania and included volunteers from Hong Kong, Japan, China, Singapore, England, Norway, Philippines, Switzerland, Argentina, Spain, Bolivia, Israel, Mexico, USA, Colombia, and Portugal. Key collaborators included co-Investigator Hong Li from Battelle Organization and Ethan Zell, Assistant Professor of Psychology from University of North Carolina at Greensboro, as well as researchers from 18 other countries.The results are reported in the September issue of the journal Social Psychological and Personality Science. Understanding the dynamics of attitudes toward action and inaction can be of benefit when developing public service announcement campaigns, health awareness messages, or other advertising campaigns, as well as understanding patterns of rest and risky behavior and how these attitudes are communicated within a culture.People from East-Asian societies can see opposites as coexisting — as in the balance that exists between “Yin” and “Yang” — and actually value action and inaction to a more similar, moderate degree than Europeans, North Americans, and Latin Americans, who, according to the study, overvalue action.Animals regulate their amount of activity through biological mechanisms that ensure sleep and wakefulness cycles. Humans have these mechanisms as well, Dr. Albarracín said, but they are also socially conditioned to be active or rest through their attitudes and beliefs. Dr. Albarracín and her team have been studying these attitudes and finding that all cultures in their research value action more than inaction. “Ideally, people should value both action and inaction,” she said, “because valuing only action could make you engage in indiscriminate, manic, even risky activity (think addictions, overeating, aggression), and valuing only inaction could make you too passive and perhaps even depressed.”For display purposes, the following list ranked from highest to lowest and developed from Dr. …

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Dueling infections: Parasitic worms limit the effects of giardia, and vice versa

Aug. 30, 2013 — If the idea of hookworms makes you shudder, consider this: Those pesky intestinal parasites may actually help your body ward off other infections, and perhaps even prevent autoimmune and other diseases.Studying members of the Tsimane, an indigenous population in the lowlands of Central Bolivia, UC Santa Barbara anthropologists Aaron Blackwell and Michael Gurven found that individuals infected by helminths — parasitic worms — were less likely than their counterparts to suffer from giardia, an intestinal malady caused by a flagellated protozoa. Similarly, those with giardia tended to be less infected by helminths. The researchers’ findings appear in the Proceedings of the Royal Society B.Treatment of one parasite also led to a greater likelihood of having the other later, the researchers found. The study used longitudinal data on 3,275 Tsimane collected over six years, which thereby permitted the authors to make more definitive causal inferences. This represents a distinct improvement over common correlative studies.”People living in developing countries are often burdened by simultaneous infections,” said Blackwell, an assistant professor of anthropology and the paper’s lead author. “The key finding in this study is that worms and giardia have antagonistic effects on one another, such that infection with one limits infection with the other.”The researchers’ findings also suggest that treating one infection might allow the other to run rampant, which raises questions about currently accepted protocols for dealing with parasites.According to Gurven, a professor of anthropology and co-director of the Tsimane Health and Life History Project, a collaboration between UCSB and the University of New Mexico, more than 1.5 billion people in the developing world have soil-transmitted intestinal worms. To determine which particular individuals are infected — and require treatment — however, is a very costly endeavor.”There are campaigns in many developing countries to give every child under five de-worming medication, but if the basic infrastructure that leads to infection doesn’t change — like sanitation and access to shoes and clean water — re-infection is likely to happen within six months,” he said. “And if intestinal worms are protective against giardia, there’s a tradeoff, and then the question is, which of the two is worse?”Diagnosis and treatment of parasites usually happen on an organism-by-organism basis, continued Gurven, a co-author of the paper. Further, he argues that in the case of hookworm and giardia, the relationship between the parasites needs to be taken into account in order to maintain the overall health of the individual involved.That one intestinal parasite has the ability to limit the pervasiveness of another also sheds light on the significance of parasites in general. …

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Anthropologists study testosterone spikes in non-competitive activities

Aug. 13, 2013 — The everyday physical activities of an isolated group of forager-farmers in central Bolivia are providing valuable information about how industrialization and its associated modern amenities may impact health and wellness.Studying short-term spikes in the testosterone levels of Tsimane men, UC Santa Barbara anthropologists Ben Trumble and Michael Gurven have found that the act of chopping down trees — a physically demanding task that is critical to successful farming and food production — results in greater increases in testosterone than does a directly competitive activity such as soccer. Their research appears in the early online edition of the journal Evolution and Human Behavior.”With the Tsimane, we see an environment that is more like that in which humans evolved, and for which our systems are calibrated,” said Trumble, a postdoctoral researcher in anthropology at UCSB and the paper’s lead author. The paper was written with Gurven, a UCSB professor of anthropology and co-director of the Tsimane Health and Life History Project, a collaboration between UCSB and the University of New Mexico.According to Trumble, whose research lies at the intersection of hormones, behavior, and the environment, testosterone levels are closely related to the availability of food energy. When young men skip even a single meal, their testosterone levels can drop as much as 10 percent. Fast for a couple of days, and they decrease to castrate levels.”The same is true for infection,” he added. “An infection from a pathogen or parasite — even injuries, burns, or surgery — all cause an immediate decrease in testosterone.”The body uses food energy for a number of critical processes. Among them are building muscle mass and maintaining proper immune function. When food energy is limited, the body has to choose between one and the other. For populations in industrialized countries like the United States, there isn’t much of a tradeoff,” Trumble said. …

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Crowdsourcing weather using smartphone batteries

Aug. 13, 2013 — Smartphones are a great way to check in on the latest weather predictions, but new research aims to use the batteries in those same smartphones to predict the weather.A group of smartphone app developers and weather experts created a way to use the temperature sensors built into smartphone batteries to crowdsource weather information. These tiny thermometers usually prevent smartphones from dangerously overheating, but the researchers discovered the battery temperatures tell a story about the environment around them.Crowdsourcing hundreds of thousands of smartphone temperature readings from phones running the popular OpenSignal Android app, the team estimated daily average temperatures for eight major cities around the world. After calibration, the team calculated air temperatures within an average of 1.5 degrees Celsius (2.7 degrees Fahrenheit) of the actual value, which should improve as more users join the system.While each of the cities already has established weather stations, according to the new method’s creators it could one day make predictions possible at a much finer scale of time and space than is currently feasible. Whereas today, weather reports typically provide one temperature for an entire city and a handful of readings expected throughout a day, the technique could lead to continuously updated weather predictions at a city block resolution.”The ultimate end is to be able to do things we’ve never been able to do before in meteorology and give those really short-term and localized predictions,” said James Robinson, co-founder of London-based app developer OpenSignal that discovered the method. “In London you can go from bright and sunny to cloudy in just a matter of minutes. We’d hope someone would be able to decide when to leave their office to get the best weather for their lunch break.”The work was published today in Geophysical Research Letters, a journal of the American Geophysical Union.Smartphone sensorsRobinson’s OpenSignal app collects information voluntarily sent from users’ phones to build accurate maps of cellphone coverage and Wi-Fi access points. The app boasts about 700,000 active users according to Robinson, about 90 percent of which opt in to providing statistics collected by their phones.Robinson originally wondered whether smartphones running on newer, 4G networks ran hotter than those running on older networks. When no difference showed up, he looked for other potential uses of the temperature information available on Android-powered devices.”Just sort of for fun we started looking to see if there was a correlation with anything else,” said Robinson. “We got some London weather data for comparison and found the two sets of temperatures were offset, but they had the same sort of shape.”While OpenSignal is available to iPhone and iPad users, the temperature readings on those devices are not accessible like on their Android counterparts.Cellphone thermometersAfter finding the correlation between smartphone and air temperatures in London, Robinson and his fellow developers assembled temperature data from other major cities where they had a large number of users. …

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Strangers invade the homes of giant bacteria

Aug. 7, 2013 — Life is not a walk in the park for the world’s largest bacteria, that live as soft, noodle-like, white strings on the bottom of the ocean depths. Without being able to fend for themselves, they get invaded by parasitic microorganisms that steal the nutrition, that they have painstakingly retreived. This newly discovered bizarre deep ocean relationship may ultimately impact ocean productivity, report researchers from University of Southern Denmark now in the scientific journal Nature.At the bottom of the eastern Pacific off Mexico we find one of the largest bacteria in the world: Thioploca. It is so large that it can be seen with the naked eye, and it lives together with other family members in bundles of long fluffy white cell strands that look like Chinese noodles. Thioploca feeds on nitrate, which it absorbs from the water, and when it has gathered a portion of nitrate, it retires to a dwelling site under the seabed. The bacteria withdraws through an up to 20 cm long sheath to its dwelling site, and when it is again ready to feed, it returns through the tube to the ocean water.”We have long thought that a surprisingly large amount of nitrate disappears here. When we investigated the case, we saw that Thioploca is not solely responsible for all nitrate removal. Inside the tubes we found some smaller cells, so-called anammox bacteria that steal nitrate from Thioploca when it retires through the sheath with its harvest of nitrate,” explains Bo Thamdrup, bio-geo-chemist at the Nordic Center for Earth Evolution (NordCEE), University of Southern Denmark.Along with colleagues from Pomona College in California and other American institutions, he describes the newly discovered symbiosis in the journal Nature.The discovery is now helping to explain why in some parts of the oceans large quantities of nutrients disappear.”The newly discovered symbiotic relationship increases nitrogen metabolism in the sea. This leads to fewer algae in the water and thus less food for marine organisms. …

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Mini-monsters of the forest floor

July 29, 2013 — A University of Utah biologist has identified 33 new species of predatory ants in Central America and the Caribbean, and named about a third of the tiny but monstrous-looking insects after ancient Mayan lords and demons.”These new ant species are the stuff of nightmares” when viewed under a microscope, says entomologist Jack Longino, a professor of biology. “Their faces are broad shields, the eyes reduced to tiny points at the edges and the fierce jaws bristling with sharp teeth.”They look a little like the monster in ‘Alien.’ They’re horrifying to look at up close. That’s sort of what makes them fun.”In a study published online Monday, July 29 in the journal Zootaxa, Longino identified and named 14 new species of the ant genus Eurhopalothrix and distinguished them from 14 other previously known species. The genus name is Greek and refers to the club-shaped hairs on many Eurhopalothrix (pronounced you-row-pal-oh-thrix) species.In another upcoming study accepted for publication in the same journal, Longino identified 19 new ant species from the genus Octostruma (pronounced oct-oh-strew-ma) and described differences from 15 other previously known species. The genus name means “eight swellings” for the ants’ eight-segmented antennas.”The new species were found mostly in small patches of forest that remain in a largely agricultural landscape, highlighting the importance of forest conservation efforts in Central America,” Longino says.The new ant species are less than one-twelfth to one-twenty-fifth of an inch long — much smaller than a rice grain or common half-inch-long household ants — and live in the rotting wood and dead leaves that litter the forest floors in Central America.”They are nearly eyeless and crawl around in leaf litter,” using primitive compound eyes to detect light but not form images. No one knows how they find their prey, presumed to be soft-bodied insects, spiders, millipedes and centipedes. But the ants are known to coat themselves with a thin layer of clay, believed to serve as camouflage.Ant Lords of Leaf LitterAmong the newly discovered and named species from forest-floor leaf litter:– Eurhopalothrix zipacna, named for a violent, crocodile-like Mayan demon and found in Guatemala and Honduras.– Eurhopalothrix xibalba, or a “place of fear,” for the underworld ruled by death gods in certain Mayan mythology. It lives from Honduras to Costa Rica.– Eurhopalothrix hunhau, for a major Mayan death god and a lord of the underworld. This species lives in Mexico and Guatemala.Some of the scary looking new species have more mundane names, such as Eurhopalothrix semicapillum, named for partial patches of hair on its face, and Octostruma convallis, named after the curved groove across its face.Longino named one species Eurhopalothrix ortizae, after Patricia Ortiz, a Costa Rican naturalist who died in a rock-fall accident this year.The horror-show faces of some of the new species feature what is known as the labrum, which is like an upper lip, and jaws that open and close sideways instead of up and down as teeth on the jaws clamp down on prey.”If you really want a movie monster that freaks people out, have the jaws go side to side,” Longino says.”Ants are everywhere,” Longino says. “They are one of the big elements of ecosystems, like birds and trees. …

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Is sexual addiction the real deal?

July 19, 2013 — Controversy exists over what some mental health experts call “hypersexuality,” or sexual “addiction.” Namely, is it a mental disorder at all, or something else? It failed to make the cut in the recently updated Diagnostic and Statistical Manual of Mental Disorders, or DSM-5, considered the bible for diagnosing mental disorders. Yet sex addiction has been blamed for ruining relationships, lives and careers.Now, for the first time, UCLA researchers have measured how the brain behaves in so-called hypersexual people who have problems regulating their viewing of sexual images. The study found that the brain response of these individuals to sexual images was not related in any way to the severity of their hypersexuality but was instead tied only to their level of sexual desire.In other words, hypersexuality did not appear to explain brain differences in sexual response any more than simply having a high libido, said senior author Nicole Prause, a researcher in the department of psychiatry at the Semel Institute for Neuroscience and Human Behavior at UCLA.”Potentially, this is an important finding,” Prause said. “It is the first time scientists have studied the brain responses specifically of people who identify as having hypersexual problems.”The study appears in the current online edition of the journal Socioaffective Neuroscience and Psychology.A diagnosis of hypersexuality or sexual addiction is typically associated with people who have sexual urges that feel out of control, who engage frequently in sexual behavior, who have suffered consequences such as divorce or economic ruin as a result of their behaviors, and who have a poor ability to reduce those behaviors.But, said Prause and her colleagues, such symptoms are not necessarily representative of an addiction — in fact, non-pathological, high sexual desire could also explain this cluster of problems.One way to tease out the difference is to measure the brain’s response to sexual-image stimuli in individuals who acknowledge having sexual problems. If they indeed suffer from hypersexuality, or sexual addiction, their brain response to visual sexual stimuli could be expected be higher, in much the same way that the brains of cocaine addicts have been shown to react to images of the drug in other studies.The study involved 52 volunteers: 39 men and 13 women, ranging in age from 18 to 39, who reported having problems controlling their viewing of sexual images. They first filled out four questionnaires covering various topics, including sexual behaviors, sexual desire, sexual compulsions, and the possible negative cognitive and behavioral outcomes of sexual behavior. Participants had scores comparable to individuals seeking help for hypersexual problems.While viewing the images, the volunteers were monitored using electroencephalography (EEG), a non-invasive technique that measures brain waves, the electrical activity generated by neurons when they communicate with each other. Specifically, the researchers measured event-related potentials, brain responses that are the direct result of a specific cognitive event.”The volunteers were shown a set of photographs that were carefully chosen to evoke pleasant or unpleasant feelings,” Prause said. “The pictures included images of dismembered bodies, people preparing food, people skiing — and, of course, sex. …

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The best defense against catastrophic storms: Mother Nature, researchers say

July 17, 2013 — Extreme weather, sea level rise and degraded coastal systems are placing people and property at greater risk along the coast. Natural habitats such as dunes and reefs are critical to protecting millions of U.S. residents and billions of dollars in property from coastal storms, according to a new study by scientists with the Natural Capital Project at the Stanford Woods Institute for the Environment.The study, “Coastal habitats shield people and property from sea-level rise and storms,” published July 14 in the journal Nature Climate Change, offers the first comprehensive map of the entire U.S. coastline that shows where and how much protection communities get from natural habitats such as sand dunes, coral reefs, sea grasses and mangroves. The likelihood and magnitude of losses can be reduced by intact ecosystems near vulnerable coastal communities.One map shows predicted exposure of the United States coastline and coastal population to sea level rise and storms in the year 2100. An interactive map can be zoomed in on for the West, Gulf or East coasts; Hawaii or Alaska; or the continental United States.”The natural environment plays a key role in protecting our nation’s coasts,” said study lead author Katie Arkema, a Woods postdoctoral scholar. “If we lose these defenses, we will either have to have massive investments in engineered defenses or risk greater damage to millions of people and billions in property.”With the release of the Obama administration’s Climate Action Plan on June 25, there is renewed interest in coastal resilience and climate adaptation planning, as well as in finding natural ways to protect America’s coastline. Billions of dollars will soon be spent on restoration activities in the Gulf of Mexico and the Eastern Seaboard affected by Hurricane Sandy. Leaders can make decisions now to factor natural capital into decisions that could have long-term benefits.”As a nation, we should be investing in nature to protect our coastal communities,” said Mary Ruckelshaus, managing director of the Natural Capital Project. “The number of people, poor families, elderly and total value of residential property that are most exposed to hazards can be reduced by half if existing coastal habitats remain fully intact.”At a moment when many coastal planners are considering their options for dealing with the impacts of sea level rise, the study provides both a national and a localized look at coastal areas where restoration and conservation of natural habitats could make the biggest difference.”Hardening our shorelines with sea walls and other costly engineering shouldn’t be the default solution,” said Peter Kareiva, the chief scientist at The Nature Conservancy and co-author of the study. …

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Maize trade disruption could have global ramifications

July 17, 2013 — New research on the global maize (corn) trade suggests that any disruptions to U.S. exports could pose food security risks for many U.S. trade partners due to the lack of trade among other producing and importing nations. The study, while not primarily focused on plant disease, population growth, climate change or the diversion of corn to non-food uses such as ethanol, suggests that significant stresses in these areas could jeopardize food security. This is particularly true of nations like Mexico, Japan and the Republic of Korea that have yet to diversify their sources.Share This:Maize is at the center of global food security as increasing demands for meat, fuel uses, and cereal crop demands increase the grain’s pivotal importance in diets worldwide. It is used as a basic raw material in producing starch, oil, protein, alcohol, food sweeteners and as a dietary staple. Disruptions in any one major exporter’s supplies could lead to price shocks. The centrality of maize means that it would become a critical food security risk if major exporters experience disruptions due to non-food diversions, plant diseases and climate impacts, according to the article.The researchers studied trade patterns from 2000-2009 and determined that the U.S. is by far the largest exporter, exporting four times as much maize as Argentina, the next largest exporter. Drs. …

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Asian origins of native American dogs confirmed

July 10, 2013 — Once thought to have been extinct, native American dogs are on the contrary thriving, according to a recent study that links these breeds to ancient Asia.The arrival of Europeans in the Americas has generally been assumed to have led to the extinction of indigenous dog breeds; but a comprehensive genetic study has found that the original population of native American dogs has been almost completely preserved, says Peter Savolainen, a researcher in evolutionary genetics at KTH Royal Institute of Technology in Stockholm.In fact, American dog breeds trace their ancestry to ancient Asia, Savolainen says. These native breeds have 30 percent or less modern replacement by European dogs, he says.”Our results confirm that American dogs are a remaining part of the indigenous American culture, which underscores the importance of preserving these populations,” he says.Savolainen’s research group, in cooperation with colleagues in Portugal, compared mitochondrial DNA from Asian and European dogs, ancient American archaeological samples, and American dog breeds, including Chihuahuas, Peruvian hairless dogs and Arctic sled dogs.They traced the American dogs’ ancestry back to East Asian and Siberian dogs, and also found direct relations between ancient American dogs and modern breeds.”It was especially exciting to find that the Mexican breed, Chihuahua, shared a DNA type uniquely with Mexican pre-Columbian samples,” he says. “This gives conclusive evidence for the Mexican ancestry of the Chihuahua.”The team also analysed stray dogs, confirming them generally to be runaway European dogs; but in Mexico and Bolivia they identified populations with high proportions of indigenous ancestry.Savolainen says that the data also suggests that the Carolina Dog, a stray dog population in the U.S., may have an indigenous American origin.Savolainen works at the Science for Life Laboratory (SciLifeLab www.scilifelab.se), a collaboration involving KTH Royal Institute of Technology, Stockholm University, the Karolinska Institutet and Uppsala University.

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Deep sea isolation: Hypersaline ‘islands’ harbor unique life

July 8, 2013 — Deep in the ocean exist super salty anoxic basins that form ‘islands’ allowing evolution to vary between communities of ciliated plankton. These unique communities are presented in BioMed Central’s open access journal BMC Microbiology, and provide an opportunity to observe multiple results of evolution from the same stock and different solutions to environmental difficulties.Share This:About five and a half million years ago the Mediterranean sea dried up. This resulted in salty sediment, known as Messinian evaporites, in basins which were covered by sea water as the area reflooded. Salts from these basins are slowly leaching out but, since this water is denser than the surrounding sea, they are unmixable and it remains a briny column.The ciliate plankton which live in these brines all began from the same stock, but over time have had the potential to evolve differently. Researchers from University of Kaiserslautern in collaboration with Woods Hole Oceanographic Institution, USA and CNR- Institute for Coastal Marine Environment, Italy, investigated how isolated these communities are, and whether there has been mixing between them and the surrounding ciliates in the sea.The researchers found that there was some mixing of ciliate communities at the interfaces immediately above four different brines, and that these communities were very similar to each other. However the communities living at the heart of the brines were very different from each other even though the physical properties of each island were the same.Dr Thorsten Stoeck who led this project said, “The isolation of these very similar habitats means that we can study alternative courses of evolution. Each of our four communities had taken a subtly different route in adapting to anoxia and hypersalinity, resulting in four very different communities. Other ancient isolated habits which also occur in the Red Sea and Gulf of Mexico may also contain ‘hot spots’ of as-of-yet unstudied and potentially highly divergent ecosystems.”Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is reprinted from materials provided by BioMed Central Limited. Note: Materials may be edited for content and length. For further information, please contact the source cited above. …

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