A study of an Early Miocene fossil from southern Siberia performed by an international team of researchers, from the National Museum in Prague, Voronezh State University and the Museum of Natural History in London, led to the surprising find that the fossil belongs to a species of aquatic beetles which is still alive today and widely distributed in Eurasia.

The study was published in the open-access journal ZooKeys.

The fossil beetle discovered in the 16-23 million years old sediments of the Irtysh River in southern Siberia belongs to the modern species Helophorus sibiricus, a member of the water scavenger beetles (Hydrophiloidea), which is at present widely distributed in Eurasia and reaches even North America. The species was originally described in 1860 by the Russian entomologist Victor Motschulsky based on specimens collected at Lake Baikal. It is aquatic and inhabits various kinds of standing waters, predominantly the grassy temporary pools. Larvae are unknown so far, but are supposed to be terrestrial and predaceous, preying on various invertebrates, as in most other species of the genus.

The Siberian fossil provides new data for the long-lasting debate among scientists about the average duration of an insect species. It was originally estimated to be ca. 2-3 million years based on the available fossil record, but slowly accumulating data begin to show that such an estimate is an oversimplification of the problem. Recently, evolutionary trees dated using molecular clocks suggested that some insect species are rather young, originating during the Ice Ages, but others may have been able to survive the last 10-20 million years until today. The long-living species had to survive the massive changes of the Earth’s climate during the last millions of years — how they managed to do so is another question for scientists to address.

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A Scripps Institution of Oceanography at UC San Diego-led research team followed the path of oxygen atoms on carbon dioxide molecules during photosynthesis to create a new way of measuring the efficiency of the world’s plant life.

A team led by postdoctoral researcher Lisa Welp considered the oxygen atoms contained in the carbon dioxide taken up by plants during photosynthesis. The ratio of two oxygen isotopes in carbon dioxide told researchers how long the CO₂ had been in the atmosphere and how fast it had passed through plants. From this, they estimated that the global rate of photosynthesis is about 25 percent faster than thought.

“It’s really hard to measure rates of photosynthesis for forests, let alone the entire globe. For a single leaf it’s not so hard, you just put it in an instrument chamber and measure the CO₂ decreasing in the chamber air,” said Welp. “But you can’t do that for an entire forest. What we have done is to use a naturally occurring marker in atmospheric CO₂ that let us track how often it ended up inside a plant leaf, and from that we estimated the mean global rate of photosynthesis over the last few decades.”

The authors of the study, published in the journal Nature, said the new estimate of the rate of global photosynthesis enabled by their method will in turn help guide other estimates of plant activity such as the capacity of forests and crops to grow. Understanding such variables is becoming increasingly important to scientists and policymakers attempting to understand the potential changes to ecosystems that can be expected from global warming.

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Research published in the October issue of The American Naturalist shows that Australian green tree frogs survive the dry season with the help of the same phenomenon that fogs up eyeglasses in the winter.

According to researchers from Charles Darwin University in Australia, tree frogs often plop themselves down outside on cool nights during the dry season in tropical Australia. When they return to their dens, condensation forms on their cold skin — just like it does on a pair of glasses when we come in from the cold. The researchers found that frogs absorb this moisture through their skin, which helps to keep them hydrated during periods of little or no rain.

Before this study, the frogs’ dry-season excursions were a bit mysterious.

“Every once in a while, we would find frogs sitting on a stick under the open sky, on nights when it was so cold they could barely move,” said Dr. Chris Tracy, who led the research. “It was a real puzzle.”

Tracy and his colleagues thought this behavior might enable the frogs collect condensation, but the hypothesis had never been tested.

The researchers designed a series of experiments using real frog dens in eucalyptus trees and artificial ones made from PVC pipe. They wanted to see if the frogs could collect enough moisture through condensation to compensate for what they lost being in the cold. They found that a cold night out cost a frog as much as .07 grams of water. However, a frog could gain nearly .4 grams, or nearly 1 percent of its total body weight, in water upon returning to the warm den.

The researchers also tested how well a frog’s skin could absorb water, and found that as much as 60 percent of each water drop could be absorbed.

The results show that frogs can use condensation to hydrate themselves. And in a place as arid as the Australian savannahs during the dry season, where there is essentially no rain from June through August, every little bit counts.

“When there’s no water available, even a small amount can mean the difference between surviving the dry season or not,” Tracy said.

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Changes in the ratio of nitrate to phosphorus in the oceans off the coasts of Korea and Japan caused by atmospheric and riverine pollutants may influence the makeup of marine plants and influence marine ecology, according to researchers from Korea and the U. S.

“Normally in a marine environment nitrate is the limiting factor, but increased nitrate in the ocean can spur growth and create a situation where phosphorus becomes the nutrient in short supply,” says Raymond G. Najjar, professor of oceanography, Penn State. “This change in nutrients could favor organisms that are better suited for high nitrate and low phosphorus.”

According to the researchers, the effects of anthropogenic nitrate pollution from the air have been shown to be significant in local lakes, streams and estuaries in Norway, Sweden and the U.S.

“This is the first evidence of increases in nitrate in ocean waters not in an enclosed estuary like the Chesapeake Bay,” said Najjar. “These are large, very deep bodies of water and it is surprising to see increased nitrate in these large seas.”

Najjar and his Korean colleagues, Kitack Lee, professor, and Tae-Wook Kim, graduate student, School of Environmental Science and Engineering, Pohang University of Science and Technology; Hee-Dong Jeong, National Fisheries Research and Development Institute; and Hae Jun Jeong, professor, School of Earth and Environmental Science, Seoul National University, studied trends in nitrate and phosphate in the coastal waters of Korea and Japan since the 1980s. They also compared the amount of nitrogen deposited from the air between 2002 and 2008 for Korea and Japan with the amounts of nitrate in the water during that same time period to show that the increased levels in the water are directly correlated to an increase in human-generated atmospheric nitrogen.

The area studied included the Yellow Sea, the Sea of Japan and the East China Sea. The researchers found that the phosphorus levels in the ocean water remained the same through time.

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Scientists have long debated about the impact on global climate of water evaporated from vegetation. New research from Carnegie’s Global Ecology department concludes that evaporated water helps cool Earth as a whole, not just the local area of evaporation, demonstrating that evaporation of water from trees and lakes could have a cooling effect on the entire atmosphere. These findings, published Sept. 14 in Environmental Research Letters, have major implications for land-use decision making.

Evaporative cooling is the process by which a local area is cooled by the energy used in the evaporation process, energy that would have otherwise heated the area’s surface. It is well known that the paving over of urban areas and the clearing of forests can contribute to local warming by decreasing local evaporative cooling, but it was not understood whether this decreased evaporation would also contribute to global warming

Earth has been getting warmer over at least the past several decades, primarily as a result of the emissions of carbon dioxide from the burning of coal, oil, and gas, as well as the clearing of forests. But because water vapor plays so many roles in the climate system, the global climate effects of changes in evaporation were not well understood.

The researchers even thought it was possible that evaporation could have a warming effect on global climate, because water vapor acts as a greenhouse gas in the atmosphere. Also, the energy taken up in evaporating water is released back into the environment when the water vapor condenses and returns to earth, mostly as rain. Globally, this cycle of evaporation and condensation moves energy around, but cannot create or destroy energy. So, evaporation cannot directly affect the global balance of energy on our planet.

The team led by George Ban-Weiss, formerly of Carnegie and currently at Lawrence Berkeley National Laboratory, included Carnegie’s Long Cao, Julia Pongratz and Ken Caldeira, as well as Govindasamy Bala of the Indian Institute of Science in Bangalore. Using a climate model, they found that increased evaporation actually had an overall cooling effect on the global climate.

Increased evaporation tends to cause clouds to form low in the atmosphere, which act to reflect the sun’s warming rays back out into space. This has a cooling influence.

“This shows us that the evaporation of water from trees and lakes in urban parks, like New York’s Central Park, not only help keep our cities cool, but also helps keep the whole planet cool,” Caldeira said. “Our research also shows that we need to improve our understanding of how our daily activities can drive changes in both local and global climate. That steam coming out of your tea-kettle may be helping to cool the Earth, but that cooling influence will be overwhelmed if that water was boiled by burning gas or coal.”

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The way in which plants space out the pores through which they breathe depends on keeping a protein active during stem cell growth, according to John Innes Centre scientists.

Plant pores, called stomata, are essential for life. When they evolved about 400 million years ago, they helped plants conquer the land. Plants absorb carbon dioxide through stomata and release oxygen and water vapour as part of Earth’s carbon and water cycles.

Stomata need to be evenly spaced to maximise breathing capacity. But how they establish an even spatial pattern during plant growth has been a mystery.

In a paper published in Science, the JIC scientists show that the ability of cells to divide and form stomata is retained in only one of the two daughter cells generated by each division. This pattern, known as stem cell behaviour, is also found in certain animal cells, like those that form skin or bone.

In the case of stomata, the stem cell property depends on a protein called SPEECHLESS (SPCH) being kept active in a single daughter cell. The daughter cell is kept at the centre of her cellular relatives through a sort of molecular dance through which the polarity of cells switches at each division. The daughter eventually forms a stoma, surrounded by non-stomatal relatives, ensuring that the stomatal pores are spaced out.

“Unravelling this mechanism was only possible because of advances in live imaging and computational modelling,” said Professor Enrico Coen from JIC, the plant science centre strategically funded by Biotechnology and Biological Sciences Research Council (BBSRC).

The computer modelling predicted rules that the scientists were able to validate experimentally in the plant Arabidopsis. They tracked various markers such as a fluorescent protein to see the patterns that formed in growing leaves.

The research could help scientists to tailor the number and arrangement of stomata to different environments. This could regulate the efficiency at which plants absorb carbon dioxide or diffuse water vapour.

The work was funded by the BBSRC, the Natural Sciences and Engineering Research Council of Canada and the US National Institutes of Health.

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Water softening techniques are very effective for removing minerals such as calcium and magnesium, which occur as positively-charged ions in “hard” water. But many heavy metals and other inorganic pollutants form negatively-charged ions in water, and existing water treatment processes to remove them are inefficient and expensive.

Chemists at the University of California, Santa Cruz, have now developed a new type of material that can soak up negatively-charged pollutants from water. The new material, which they call SLUG-26, could be used to treat polluted water through an ion exchange process similar to water softening. In a water softener, sodium ions weakly attached to a negatively-charged resin are exchanged for the hard-water minerals, which are held more tightly by the resin. SLUG-26 provides a positively-charged substrate that can exchange a nontoxic negative ion for the negatively-charged pollutants.

“Our goal for the past 12 years has been to make materials that can trap pollutants, and we finally got what we wanted. The data show that the exchange process works,” said Scott Oliver, associate professor of chemistry at UC Santa Cruz.

The chemical name for SLUG-26 is copper hydroxide ethanedisulfonate. It has a layered structure of positively-charged two-dimensional sheets with a high capacity for holding onto negative ions. Oliver and UCSC graduate student Honghan Fei described the compound in a paper that will be published in the journal Angewandte Chemie and is currently available online.

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A study led by scientists at the University of Valencia (Spain) characterizes eleven zebra mussel populations in the Ebro and the Júcar River Basin District and concludes that the arrival of this exotic species to Spanish river basins is “virtually irreversible.” These research results, however, will help devise specific control strategies.

Scientists from the Faculty of Biological Sciences — University of Valencia have led a statewide project funded by the Ministry of Environment with 690,000 Euros to characterize eleven Spanish populations of zebra mussels (Dreissena polymorpha). Project leader Professor Amparo Torreblanca of the Department of Functional Biology and Physical Anthropology explains that the mussel “is capable of adapting to different environmental conditions, including chemical pollution, and shows a prolonged reproductive period.”

The comprehensive ecophysiological and genetic characterization of zebra mussel populations developed by researchers at the University of Valencia together with the Spanish National Research Council (CSIC) (through the Institute of Environmental Diagnosis and Water Research (IADEA) of Barcelona and the Institute of Aquaculture Torre de la Sal (IATS) of Castelló) will enable governments to devise specific strategies of control, as well as to create new methods to combat its future spreading in natural water areas or enclosed facilities. Moreover, the high rate of reproduction detected in the hormonal study suggests that the practice of water sports such as canoeing “should imply a strict adherence to the recommendations of the public bodies that manage the water resources in order to prevent its spread to other rivers of the peninsula or the continent, because mussel larvae easily hook to boats,” says Torreblanca.

The zebra mussel is an invasive species that has proliferated in rivers and lakes in Spain and North America in recent decades. It arrived from the basins of the Black and Caspian seas, and is a serious environmental and socioeconomic problem. In Spain, the first populations were detected in 2001 in the Flix reservoir, from where there was a gradual spread to other reservoirs in the Ebro basin and other points of ecological interest until fully colonizing the basin. In addition, river Júcar was affected. The first population was found here in 2005 in the Sitjar reservoir on the river Mijares, and is now stabilized according to the researchers, while in the swamp Forata in Magro, a tributary of Júcar, the zebra mussel was found in 2006 but in the last two years there has been no sign of larvae. However, one can not completely rule out their presence. This invasion, according to the work coordinated by Amparo Torreblanca, “has not been produced directly from the original basins, but has come from Western populations, ie from areas geographically much closer.”

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A deep-sea mystery has been solved with the discovery that copepods — tiny 3-millimeter-long marine animals eaten by herring, cod and mackerel — use the same buoyancy control as whales.

Reporting this week in the journal Limnology and Oceanography, researchers from British Antarctic Survey describe how Southern Ocean copepods — a crustacean rich in omega-3 oil — ‘hibernates’ in the deep ocean during winter when seas are stormy and food scarce. To reach the ocean depths the copepod’s oily body fluids undergo a remarkable transformation. As the animals swim deeper, water pressure triggers a process that converts their oil to a more solid form rather like the consistency of butter. This change in density acts like a ‘diver’s weight belt’, enabling them to be neutrally buoyant and spend winter in deep waters without wasting energy on constant swimming.

Lead author from British Antarctic Survey, Dr David Pond says, “This work is of particular value from a number of angles. Copepods may be exceptionally small creatures but they represent a vast reserve of ocean ‘biomass’ that provides a crucial component of the food chain.

“We’ve known for some time that there is a link between the copepod’s large stores of energy-rich oil and ‘hibernation’ behaviour, but this is the first time that we’ve been able to understand the exact relationship between these two elements in the animal’s life cycle. This discovery is a breakthrough and will help enormously with the development of simulations of their behaviour.

It’s fascinating also to think that the largest and the smallest marine animals share this remarkable ability to change their body fats to adjust their buoyancy.”

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New research focusing on the Houston area suggests that widespread urban development alters weather patterns in a way that can make it easier for pollutants to accumulate during warm summer weather instead of being blown out to sea.

The international study, led by the National Center for Atmospheric Research (NCAR), could have implications for the air quality of fast-growing coastal cities in the United States and other midlatitude regions overseas. The reason: the proliferation of strip malls, subdivisions, and other paved areas may interfere with breezes needed to clear away smog and other pollution.

The research team combined extensive atmospheric measurements with computer simulations to examine the impact of pavement on breezes in Houston. They found that, because pavement soaks up heat and keeps land areas relatively warm overnight, the contrast between land and sea temperatures is reduced during the summer. This in turn causes a reduction in nighttime winds.

In addition, built structures interfere with local winds and contribute to relatively stagnant afternoon weather conditions.

“The developed area of Houston has a major impact on local air pollution,” says NCAR scientist Fei Chen, lead author of the new study. “If the city continues to expand, it’s going to make the winds even weaker in the summertime, and that will make air pollution much worse.”

While cautioning that more work is needed to better understand the impact of urban development on wind patterns, Chen says the research can eventually help forecasters improve projections of major pollution events. Policymakers might also consider new approaches to development as cities work to clean up unhealthy air.

The article will be published this month in the Journal of Geophysical Research-Atmospheres, a publication of the American Geophysical Union. The research was funded by the U.S. Air Force Weather Agency, the U.S. Defense Threat Reduction Agency, and the National Science Foundation, NCAR’s sponsor. In addition to NCAR, the authors are affiliated with the China Meteorological Administration, the U.S. National Oceanic and Atmospheric Administration, and the University of Tsukuba in Japan. The research built on a number of previous studies into the influence of urban areas on air pollution.

Cleansing the air with more parks and lakes?

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