Amphibian experts have long wrangled over the origins of the Greenhouse frog (Eleutherodactylus planirostris) and the Cuban treefrog (Osteopilus septentrionalis). The two species of invasive frog which are hopping their way through Florida probably got to the state by hitching a ride on floating debris from Cuba, according to a study published on Wednesday, reports AFP.

The two species are widespread across the Caribbean, but were first spotted in the Florida Keys — the island chain that starts at Florida’s southeastern tip — in the mid-1800s. Years later, both began became firmly established on the mainland and embarked on a relentless advance.

Today, the Greenhouse frog has established colonies as far north as Alabama, while the Cuban treefrog can be found all around the southern Florida coastline.

Scientists led by Blair Hedges at Pennsylvania State University analyzed the frogs’ DNA to identify the amphibians’ closest native relatives, which would tease out clues about this unusual migration.

The Greenhouse frog has been shown to originate from a small area of western Cuba, while the Cuban treefrog came from at least two sources in Cuba, of which the best bet is a remote peninsula in the western part of the island.

The team believes that the two species came to Florida thousands of years ago, quite possibly by climbing on board vegetation that then floated like a raft across the narrow strait.

The frogs have adapted over the years to the colder winters of Florida and this enabled them to spread northwards when transport and commerce links developed in the mid-20th century. “Both of them could have come across (to Florida) naturally, not by swimming, because these frogs would die pretty quickly in salt water, but by floating across on vegetation,” Hedges said in a phone interview with AFP.

“There are plenty of examples of flotsam crossings, on short distances as well as long distances, even across oceans. These frogs, especially the treefrog, are on many small islands in the Caribbean which have no humans, so clearly they get around. There’s no other way they could have got to those islands other than by floating.”

Hedges added: “What we’re speculating in this paper is that if they were there on the Keys on their own for thousands of years, they could have adapted to a more continental climate, making them better invasive species and when they made their way up into Florida, that may explain why they have done so well.”

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Image Caption: A Cuban treefrog Osteopilus septentrionalis. Credit: Wikipedia   

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On the Net:

Pennsylvania State University

They said it could be done and now they’ve done it. What’s more, they did it with a GRIN. A team of researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Berkeley, have carried out the first experimental demonstration of GRIN ““ for gradient index ““ plasmonics, a hybrid technology that opens the door to a wide range of exotic optics, including superfast computers based on light rather than electronic signals, ultra-powerful optical microscopes able to resolve DNA molecules with visible light, and “invisibility” carpet-cloaking devices.

Working with composites featuring a dielectric (non-conducting) material on a metal substrate, and “grey-scale” electron beam lithography, a standard method in the computer chip industry for patterning 3-D surface topographies, the researchers have fabricated highly efficient plasmonic versions of Luneburg and Eaton lenses. A Luneburg lens focuses light from all directions equally well, and an Eaton lens bends light 90 degrees from all incoming directions.

“This past year, we used computer simulations to demonstrate that with only moderate modifications of an isotropic dielectric material in a dielectric-metal composite, it would be possible to achieve practical transformation optics results,” says Xiang Zhang, who led this research. “Our GRIN plasmonics technique provides a practical way for routing light at very small scales and producing efficient functional plasmonic devices.”

Zhang, a principal investigator with Berkeley Lab’s Materials Sciences Division and director of UC Berkeley’s Nano-scale Science and Engineering Center (SINAM), is the corresponding author of a paper in the journal Nature Nanotechnology, describing this work titled, “Plasmonic Luneburg and Eaton Lenses.” Co-authoring the paper were Thomas Zentgraf, Yongmin Liu, Maiken Mikkelsen and Jason Valentine.

GRIN plasmonics combines methodologies from transformation optics and plasmonics, two rising new fields of science that could revolutionize what we are able to do with light. In transformation optics, the physical space through which light travels is warped to control the light’s trajectory, similar to the way in which outer space is warped by a massive object under Einstein’s relativity theory. In plasmonics, light is confined in dimensions smaller than the wavelength of photons in free space, making it possible to match the different length-scales associated with photonics and electronics in a single nanoscale device.

“Applying transformation optics to plasmonics allows for precise control of strongly confined light waves in the context of two-dimensional optics,” Zhang says. “Our technique is analogous to the well-known GRIN optics technique, whereas previous plasmonic techniques were realized by discrete structuring of the metal surface in a metal-dielectric composite.”

Like all plasmonic technologies, GRIN plasmonics starts with an electronic surface wave that rolls through the conduction electrons on a metal. Just as the energy in a wave of light is carried in a quantized particle-like unit called a photon, so, too, is plasmonic energy carried in a quasi-particle called a plasmon. Plasmons will interact with photons at the interface of a metal and dielectric to form yet another quasi-particle, a surface plasmon polariton (SPP).

The Luneburg and Eaton lenses fabricated by Zhang and his co-authors interacted with SPPs rather than photons. To make these lenses, the researchers worked with a thin dielectric film (a thermplastic called PMMA) on top of a gold surface. When applying grey-scale electron beam lithography, the researchers exposed the dielectric film to an electron beam that was varied in dosage (charge per unit area) as it moved across the film’s surface. This resulted in highly controlled differences in film thickness across the length of the dielectric that altered the local propagation of SPPs. In turn, the “mode index,” which determines how fast the SPPs will propagate, is altered so that the direction of the SPPs can be influenced.

“By adiabatically tailoring the topology of the dielectric layer adjacent to the metal surface, we’re able to continuously modify the mode index of SPPs,” says  Zentgraf. “As a result, we can manipulate the flow of SPPs with a greater degree of freedom in the context of two-dimensional optics.”

Says Liu, “The practicality of working only with the purely dielectric material to transform SPPs is a big selling point for GRIN plasmonics. Controlling the physical properties of metals on the nanometer length-scale, which is the penetration depth of electromagnetic waves associated with SPPs extending below the metal surfaces, is beyond the reach of existing nanofabrication techniques.”

Adds Zentgraf, “Our approach has the potential to achieve low-loss functional plasmonic elements with a standard fabrication technology that is fully compatible with active plasmonics.”

In the Nature Nanotechnology paper, the researchers say that inefficiencies in plasmonic devices due to SPPs lost through scattering could be reduced even further by incorporating various SPP gain materials, such as fluorescent dye molecules, directly into the dielectric. This, they say, would lead to an increased propagation distance that is highly desired for optical and plasmonic devices. It should also enable the realization of two-dimensional plasmonic elements beyond the Luneburg and Eaton lenses.

Says Mikkelsen, “GRIN plasmonics can be immediately applied to the design and production of various plasmonic elements, such as waveguides and beam splitters,  to improve the performance of integrated plasmonics. Currently we are working on more complex, transformational plasmonic devices, such as plasmonic collimators, single plasmonic elements with multiple functions, and plasmonic lenses with enhanced performance.”

This research was supported by the U.S. Army Research Office and the National Science Foundation’s Nano-scale Science and Engineering Center.

Lawrence Berkeley National Laboratory is a U.S. Department of Energy (DOE) national laboratory managed by the University of California for the DOE Office of Science. Berkeley Lab provides solutions to the world’s most urgent scientific challenges including sustainable energy, climate change, human health, and a better understanding of matter and force in the universe. It is a world leader in improving our lives through team science, advanced computing, and innovative technology. Visit our Website at www.lbl.gov

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On the Net:

• Berkeley Lab News Center
• Nature Nanotechnology

A United Nations-backed research report showed Monday that 2010 was among the worst years on record for natural disasters over the past 20 years, leaving upwards of 300,000 people dead, and countless more injured and/or displaced.

Nearly two-thirds of the total death toll, came from the devastating Haiti earthquake a year ago, that claimed the lives of more than 222,500 people, according to the Belgium-based Center for Research on the Epidemiology of Disasters (CRED).

Last summer’s heatwave in Russia was the second deadliest disaster of the year, leaving 55,736 people dead according to figures it compiled from insurers and media reports of official sources.

Margareta Wahlstroem, UN special representative for disaster risk reduction, told AFP that the 2010 was “one of the worst in decades in terms of the number of people killed and in terms of economic losses.”

“These figures are bad, but could be seen as benign in years to come,” she said, pointing to the impact of unplanned growth of urban areas, environmental degradation and climate change.

The economic cost of the 373 major disasters recorded in 2010 reached 109 billion dollars. Of that, an estimated 30 billion dollars in damage stemmed from the powerful earthquake that hit Chile in February. The temblor unleashed a tsunami that swept away villages and claimed most of the 521 lives lost in the quake.

China’s summer flooding and landslides caused around 18 billion dollars in damage, while Pakistan deluges cost 9.5 billion dollars, according to CRED’s annual study.

While Haiti is still struggling to recover from the earthquake that devastated most of the capital city of Port-au-Prince, it ranked lower on the global economic scale with an estimated 8 billion dollars in damage.

Of the 207 million people affected by disasters worldwide last year, Asians accounted for 89 percent of those numbers, according to CRED.

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On the Net:

• Center for Research on the Epidemiology of Disasters (CRED)
• Image Courtesy Pablo Trincado/Wikipedia

A study done at Carlos III University of Madrid (UC3M) identifies and characterizes the users who upload contents on the main P2P piracy networks on Internet and points out the incentives that they find to carrying out this activity.

The research study examines the behavior of the users who are responsible for publishing over 55,000 files on the two main portals (Mininova and The Pirate Bay) of BitTorrent, the most popular P2P application for file-sharing on Internet, where some users publish contents that are then exchanged with up to tens of thousands of internet users. Their growing popularity is mostly due to the availability of contents that are of great interest, such a recently released films in the cinemas, or episodes of a variety of television series.

Users who publish contents on BitTorrent dedicate a large part of their own resources (bandwidth, storage capacity) and assume the risks involved in publishing contents that are protected by copyright laws. So, is this altruistic behavior or is there some type of economic incentive at work? “The success of BitTorrent is due to the fact that a few users make a large number of contents available in exchange for receiving economic benefits”, explain the authors of a study carried out by the Telematic Engineering Department of the UC3M, Professors Rub©n Cuevas, Carmen Guerrero and ÃÂngel Cuevas. Their analysis demonstrates that a small group of users of these applications (around one hundred) is responsible for 66 percent of the content that is published and 75 percent of the downloads. In other words: the great success of a massively used application like BitTorrent depends on a few users.

The study by the researchers at this public university in Madrid, in collaboration with scientists at the IMDEA Networks Institute, the University of Oregon (USA) and the Technical University of Darmstadt (Germany), identifies who these users are and what their incentives for massively publishing contents are. Basically, there are two different profiles. In one group there are the so-called “fake publishers”, organizations fighting illegal downloading and malicious users who publish a large quantity of false files in order to protect copyrights and spread infected software, respectively. The other group includes a small number of users (known as “top publishers”) who massively publish contents on BitTorrent and make a profit off of this activity, basically from on-line advertising and, to a lesser degree, from VIP subscriptions held by users who wish to speed up the downloading of the contents. “If these users lose interest in this activity or are eliminated from the system, BitTorrent’s traffic will be drastically reduced”, the authors of the study predict.

To carry out this research, these scientists have developed a tool that facilitates the gathering of relevant information related to thousands of files that are shared through the BitTorrent application. By means of this system, they were able to access the name of the user who published the content, his/her IP address (which provides the user’s city, country and service provider’s name ““ ISP- as well) and the IP address of those users who later used the BitTorrent application to download the contents.. “In order to remain anonymous, – explains Professor Rub©n Cuevas – many of them rent servers from companies that perform this service and then publish contents from those servers”.

The future of P2P networks

If an application such as BitTorrent’s great success depends on a few users who publish a lot of contents, what will happen if those users lose interest in this activity or are eliminated from the system (through legal actions against piracy, for example)? If other users moved in on its space, would the application survive of not? The article ends with this question, which asks us to reflect on the future and the fragility of this type of file exchange network. “In our opinion ““ the authors of the study comment ““ the success of BitTorrent lies in the availability of popular contents which are typically protected by copyright law, and people who take the risk of publishing those contents, do it because they receive an economic benefit in exchange for doing so”. Therefore, if, in the future, these users lost their incentive, either because of a decrease in advertising income or due to having to pay very expensive fines, BitTorrent would very likely cease to offer these contents, which would make people stop using the application on a massive scale. “At the present time, when the creators of contents, internet user associations and political parties are arguing about Internet piracy with regard to the controversial Sinde Law (note: ÃÂngeles González Sinde is the Spanish Minister of Culture), studies like this one are important to real understanding of the true nature of P2P content distribution networks and the economic model that is behind them”, the researchers conclude.

The study, titled “Is Content Publishing in BitTorrent Altruistic or Profit Driven?”, was recently presented at the ACM International Conference on emerging Networking Experiments and Technologies – CoNEXT, one of the most prestigious congresses in the area of communication networks, which held its sixth edition at the end of 2010 at Drexel University (Philadelphia, USA). The authors are Rub©n Cuevas, Carmen Guerrero and ÃÂngel Cuevas, of UC3M, Michal Kryzcka, of the IMDEA Networks Institute, Sebastian Kaune, from the Technical University of de Darmstadt (Germany) and Reza Rejaie, from the University of Oregon (EEUU).

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On the Net:

• Universidad Carlos III de Madrid

Global warming is already affecting the earth in a variety of ways that demand our attention. Now, research carried out at the Hebrew University of Jerusalem indicates that many tree species might become extinct due to climate change if no action is taken in time.

According to the research, trees which disperse their seeds by wind, such as pines and maples, will be unable to spread at a pace that can cope with expected climate changes.

The research, which focused on the ecological consequences of expected changes in the climate and the environment on tree spread, was conducted by Prof. Ran Nathan, head of the Alexander Silberman Institute of Life Science at the Hebrew University; his student, Nir Horvitz; and researchers from abroad.

Climate changes, which can be sensed already today and which are expected to continue in the next 50 years, include the increase of carbon dioxide concentration in the air and a reduction of surface wind speed in many areas. On the basis of earlier work, elevated concentration of carbon dioxide is expected to cause trees to produce many more seeds and to reach maturity earlier than under current conditions, hence speeding up their spread. On the other hand, the weakening of wind speed in certain areas should reduce spread rate of these trees. The balance between these opposing forces remained unknown.

Furthermore, it was unclear whether even the projected increase in wind speed in certain areas, together with the higher seed production and earlier maturation, will result in a fast enough spread of trees in order to be sufficient to match the climate changes.

These questions were examined in this study for the first time. Surprisingly, the results show that changes in wind speed, either the projected increase or decrease, have negligible effects on the rate of wind-driven spread of these species. The effects of increased seed production and earlier maturation is that which prevails, giving rise to faster spread in the future compared to current conditions. Still, this research showed that the faster spread predicted for these trees in the future will be much slower than the expected poleward shift of climate (temperature) ranges. Consequently, these tree species might not be able to withstand the climate change.

“Our research indicates that the natural wind-driven spread of many species of trees will increase, but will occur at a significantly slower pace than that which will be required to cope with the changes in surface temperature,” said Prof. Nathan. “This will raise extinction risk of many tree populations because they will not be able to track the shift in their natural habitats which currently supply them with favorable conditions for establishment and reproduction. As a result, the composition of different tree species in future forests is expected to change and their areas might be reduced, the goods and services that these forests provide for man might be harmed, and wide-ranging steps will have to be taken to ensure seed dispersal in a controlled, directed manner.”

The new research, published in the journal Ecology Letters is based on a unique, fully mechanistic model developed to predict trends in plant spread. This model is the first to consider how projected changes in biological and environmental factors would impact tree spread in future environments. Predictions which were made until now were founded on past trends and did not take into consideration the expected future changes in the key biological and environmental factors that determine plant spread.

In Israel, the research has bearing on various native tree species whose seeds are dispersed by the wind, such as Aleppo pine, Syrian maple and Syrian ash. The model that has been developed will be useful also in predicting the invasive spread of alien tree species, such as the tree of heaven, into Israeli natural habitats.

Trees with wind-dispersed seeds are mainly common in forests of North America and Eurasia. The current research points to the need to take human action to insure the dispersal of the seeds of these trees within the next half century, in view of the expected climate changes.

“It is important for those responsible for forest management in many parts of the world to understand that nature alone will not do the job,” said Prof. Nathan. “Human action will be required to ensure in a controlled manner the minimization of unexpected detrimental byproducts, and that those trees which are very important for global ecological processes will not become extinct,” he said. “These forests are important in many ways to man, including the supply of wood, the safeguarding of water quality, and the provision of recreation and tourism facilities.”

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Image Caption: This is a typical Israeli pine tree. Credit: Ophir Altsein

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On the Net:

• The Hebrew University of Jerusalem
• Ecology Letters

The key to preserving the extraordinary richness and beauty of the world’s coral reefs through the coming period of fragmentation caused by climate change lies in a better understanding of how newborn coral larvae disperse across the oceans to settle and grow on new reefs.

Research by scientists at the ARC Centre of Excellence for Coral Reef Studies is throwing new light on the survival and settlement rates of larvae from different coral species, as a basis for predicting how fast coral species might change where they live in response to climate change.

“Coral larvae are weak swimmers, and they don’t feed. They are swept around the ocean by currents and have to find a place to settle and start to grow before they run out of energy,” says Professor Sean Connolly of CoECRS and James Cook University.

“Understanding these dispersal patterns, the rate at which the larvae perish, and the rate at which they lose the ability to settle when they do arrive at a reef, hold the key to predicting how quickly a coral species can move with its preferred environments as climate change renders unsuitable parts of its current habitat.”

This information will also help in the management of existing coral reefs, under siege from ocean warming, acidification and other human impacts, he adds. If managers know the where the young corals come from that renew a damaged reef, they can take steps to limit human pressures such as fishing, coral damage or polluted runoff accordingly.

The world’s coral scientists and managers often rely on mathematical models to predict the dispersal and settlement of coral larvae, as a key part of understanding how interconnected and resilient a reef may be. However, existing models do not take good account of the rates at which coral larvae in the wild die or lose competence to settle.

In a series of groundbreaking experiments, Dr Andrew Baird has measured both the survival rates and ability to settle of larvae for five different coral species. “I noticed that the ability of the larvae to settle increased sharply after 3 to 5 days, peaked at about 1-2 weeks and then tailed off very gradually,” Dr Baird says. “Some larvae lost the ability to settle very quickly, but others from the same batch could still settle even 100 days after hatching. This suggested that the current models for predicting coral dispersal were likely to be inaccurate.”

Armed with these new findings, Baird then approached Connolly to develop a new generation of models that could better capture this high variation in settlement ability.

Modeling these wide variations has helped to resolve an important scientific puzzle, Professor Connolly says – how coral species can show substantial genetic differences between nearby reefs, but still disperse far enough to be very geographically widespread.

“Our new models indicate that more larvae than we thought should settle very close to home, perhaps on the same reef or one next door. At the same time, a small proportion of stellar performers can survive for longer, and travel further, than previously thought,” says Connolly.

This, say the researchers, provides some hope that coral species may be able to “migrate” with climate change – dispersing their larvae towards cooler areas when their current habitat gets too hot to survive.

Their paper “Estimating dispersal potential for marine larvae: dynamic models applied to scleractinian corals” by Sean R Connolly and Andrew H Baird appears in the latest issue of the journal Ecology, No 91, 2010.

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On the Net:

• ARC Centre of Excellence for Coral Reef Studies
• James Cook University
• Ecology

Catalan researchers have studied the marine trophic network in Mauritania, on the north west coast of Africa, which is an extremely heavily exploited fishing area, as well as being home to two of the world’s most threatened species of marine mammal ““ the monk seal and the Atlantic hump-backed dolphin. The results of the study show that industrial and traditional fishing activities along the coast are putting these mammals and local marine ecosystems at great danger.

The researchers studied the local marine trophic network off the north west coast of Africa, and by analyzing stable carbon and nitrogen isotopes were able to verify the distribution and trophic position of 13 mammal species and also that of other species of macro seaweed, marine plants, fish, molluscs, turtles and phytoplankton, which had never been studied before.

The monk seal (Monachus monachus) and the Atlantic hump-backed dolphin (Sousa teuszii) are “the most coastal species of the whole area studied, and are the only ones occupying this marine ecosystem”, Ana M. Pinela, lead author of the study and a researcher at the University of Barcelona (UB), tells SINC.

The Portuguese scientist says this area, which is so “extremely” over-exploited by both industrial and traditional fishing “should be a conservation priority for these species, which are important for biodiversity. If they disappear, it would be hard for others to take their place”. This would cause a “serious” imbalance “at all levels” in local coastal ecosystems, which would remain without two super-predators that are “essential” for them to function properly.

The study, which has been published in Marine Ecology Progress Series, shows the importance of the predators Monachus monachus and Sousa teuszii for the proper functioning of coastal ecosystems in Mauritania.

The killer whale (Orcinus orca), which is also present in Mauritania, feeds at the same trophic level as the monk seal, meaning it feeds on fish, and not on marine mammals as it does off some other coasts. However, “its range is much more pelagic (of open oceans)”, says Pinela, who has described the offshore ecotype of the killer whales in this region for the first time.

“Unprecedented” fishing exploitation

“Mauritania contains some of the most heavily-exploited fisheries habitats in the whole world, with one of the world’s largest fisheries stocks, which is subject to very little regulation, inspection or control”, explains the researcher. Two of the world’s most threatened species live off this coast ““ the monk seal, which is on the verge of extinction, and the hump-backed dolphin, which has a very limited geographic range and is little known.

The scientists say conservation of these coastal areas should be “a priority”. “The Mauritanian Government and international agencies should more strongly monitor both industrial and traditional fisheries exploitation both in deep sea and coastal areas”, says Pinela. Over-fishing and the over-exploitation of resources limits the availability of prey for these species and damages ecosystems.

The research team is calling for “more diligent” regulation of such fishing practices, monitoring and control of the fishing fleet, “be it Mauritanian or international”, and the implementation of sustainable fishing off the north west of Africa.

In addition, estimates should be made of fish abundance and catches in the entire study area, because it is “a biodiversity hotspot that is home to a great diversity of marine mammals”, concludes Pinela.

References: Pinela, A.M.; Borrell, A.; Cardona, L.; Aguilar, A. “Stable isotope analysis reveals habitat partitioning among marine mammals off the NW African coast and unique trophic niches for two globally threatened species” Marine Ecology-Progress Series 416: 295-306, 2010

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Image Caption: The monk seal and hump-backed dolphin are threatened by fishing activities off coast of Mauritania. Credit: Alex Aguilar

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On the Net:

• FECYT – Spanish Foundation for Science and Technology
• Marine Ecology-Progress Series

Time is running out to visit the tomb of Tutankhamen, as officials with Egypt’s Supreme Council of Antiquities have announced plans to close it to tourists by the end of the year.

The tomb, which was discovered some 89 years ago, has been damaged as a result of the many visitors it has received, particularly over the past three decades, according to a Monday report in the Australian newspaper The Sunday Times. Instead, visitors will be directed to a soon-to-be-created replica of the tomb in Luxor, while the original will be closed down for preservation purposes.

“There’s no alternative. Closing the tombs is the only way to preserve them,” Dr. Zahi Hawass, Egypt’s antiquities chief, told The Sunday Times. “People’s respiration, the humidity they bring into the tombs, their sweat, the fact that they use flashes when taking pictures–all this damages the tombs.”

“If I don’t build this ‘Valley of the Replicas’, the originals will be destroyed in less than 100 years,” Dr. Hawass added. “That would be a disaster for history.”

The replica of Tutankhamen’s tomb should be ready within a year’s time, Dr. Hawass said. Currently, the Supreme Council of Antiquities is attempting to raise funds from private donors for the project, which according to The Sunday Times will cost approximately $10 million.

According to Mike Pitts, Editor of British Archaeology, it was only a matter of time before this happened.

“There can be no disputing the problem,” Pitts said in an article written for the Guardian on Monday, noting that once Howard Carter discovered the tomb in 1922, “It was recognized immediately that the sterile environment had been compromised: Carter’s chemist found ‘air-infections’ the day after they broke in. Those were nothing, however, compared with the humidity, fungi and dust wafted through the tomb by a thousand or more visitors a day.”

“Cue staining, crumbling and erosion of the paint. Short of sand-blasting it, you would be hard pushed to devise a more efficient mechanism for destroying the 3,300-year-old art,” he said, adding that the problem was “affects ancient sites around the world”¦ Heritage tourism may be good for economies but, badly managed, it harms the heritage. It’s right that our access should be controlled.”

Pitts added that advances in technology should make the replica of Tutankhamen’s tomb “visually indistinguishable from the original; and you can see it with better lighting and access.”

“Indeed, the replication process is so precise, it brings new insights to the original, helping academics and tour guides alike. No, it’s not the real tomb. But it is a real facsimile, and when you visit you will become part of a cutting-edge research project,” he added.

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On the Net:

• Supreme Council of Antiquities
• British Archaeology

Some of the most intense emotions people feel occur during a conflict in a romantic relationship. Now, new research from Baylor University psychologists shows that how each person perceives the other partner’s emotion during a conflict greatly influences different types of thoughts, feelings and reactions in themselves.

Dr. Keith Sanford, a clinical psychologist and an associate professor in Baylor’s department of psychology and neuroscience, College of Arts and Sciences, and his research team studied 105 college students in romantic relationships as they communicated through different arguments over an eight-week period. Sanford focused on how emotion changed within each person across episodes of relationship conflict. They found demonstrated links between different types of emotion, different types of underlying concern, and different types of perceived partner emotion.

Sanford distinguished between two types of negative emotion as “hard” and “soft.” “Hard” emotion is associated with asserting power, whereas “soft” emotion is associated with expressing vulnerability. Sanford’s research also identified a type of underlying concern as “perceived threat,” which involves a perception that one’s partner is being hostile, critical, blaming or controlling. Another type of concern is called “perceived neglect,” which involves a perception that one’s partner is failing to make a desired contribution or failing to demonstrate an ideal level of commitment or investment in the relationship.

Sanford said the results show that people perceive a threat to their control, power and status in the relationship when they observe an increase in partner hard emotion and they perceive partner neglect when they observe an increase in partner flat emotion or a decrease in partner soft emotion. Both perceived threat and perceived neglect, in turn, are associated with increases in one’s own hard and soft emotions, with the effects for perceived neglect being stronger than the effects for perceived threat.

“In other words, what you perceive your partner to be feeling influences different types of thoughts, feelings and reactions in yourself, whether what you perceive is actually correct,” Sanford said. “In a lot of ways, this study confirms scientifically what we would have expected. Previously, we did not actually know that these specific linkages existed, but they are clearly theoretically expected. If a person perceives the other as angry, they will perceive a threat so they will respond with a hard emotion like anger or blame. Likewise, if a person is perceived to be sad or vulnerable, they will perceive a neglect and will respond either flat or soft.”

The study appeared in the journal Personal Relationships.

Sanford said some of the most interesting results in the study pertain to a complex pattern of associations observed for soft emotion. As expected, partner soft emotion was associated with decreased concerns over neglect, whereas self soft emotion was associated with increased concerns over neglect. Sanford said this is consistent with the idea that soft emotion is a socially focused emotion, often triggered by attachment-related concerns, and that expressions of soft emotion signal one’s own desire and willingness to invest in a relationship.

The study was supported in part by funds from the Faculty Research Investment Program and the Vice Provost for Research at Baylor.

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On the Net:

• Baylor University
• Personal Relationships

During the first part of the Bronze Age in the Carpathian Basin in Central Europe, a large proportion of the population lived in what are known as tell-building societies. A thesis in archaeology from the University of Gothenburg (Sweden) shows that the leaders of these societies had the ability to combine several sources of power in an effective way in order to dominate the rest of the population, which contributed towards creating a notably stable social system.

Tell-building societies are named after a distinct form of settlements with a high density of population and construction, which over the course of time accumulated such thick cultural layers that they took on the shape of low mounds.

On the basis of a discussion and analysis of previously published material from the Carpathian Basin and new findings from the tell settlement Százhalombatta-Földvár in Hungary, the author of the thesis, Claes Uhn©r, describes the ways in which leaders could exercise power. Tell-building societies had relatively advanced economies. The subsistence economy, which was based on agricultural production and animal husbandry, produced a good return, and the societies were involved in regional and long-distance exchange of bronzes and other valuable craft products.

“By exercising a degree of control over these parts of the economy, it was possible for leaders to finance political activities and power-exerting organizations,” says Uhn©r. He shows in his thesis that, through military power, leaders were able to control surrounding settlements from fortified tells. As the majority of these settlements were situated next to rivers and other natural transport routes, they could demand tribute from passing trade expeditions and act as intermediaries in the exchange of goods that took place in the region. In addition, a large tell was a manifestation of a successful society with a long history. This situation made it possible for leaders to use the cultural traditions of the society in ideological power strategies.

“The tells served as physical manifestations of a social system that worked well, which legitimized the social position of the elites and their right to lead. An important conclusion drawn by Uhn©r is that the sources of power could be used in strategies where they supported each other. Economic power made it possible to master military and ideological means of power. Military power was utilized to safeguard economic and ideological resources, while ideology legitimized the social system. This was largely possible because the tell settlements served as political power centers. Redistribution of staples and specialized production was attached to these sites, and they had key military and ideological significance. “By controlling tells and the activities carried out in them, leaders

had an organizational advantage over the rest of the population, and others found it very difficult to build up competing power positions,” says Uhn©r.

During the first part of the Bronze Age in the Carpathian Basin in Central Europe, a large proportion of the population lived in what are known as tell-building societies. A thesis in archaeology from the University of Gothenburg shows that the leaders of these societies had the ability to combine several sources of power in an effective way in order to dominate the rest of the population, which contributed towards creating a notably stable social system. Tell-building societies are named after a distinct form of settlements with a high density of population and construction, which over the course of time accumulated such thick cultural layers that they took on the shape of low mounds.

On the basis of a discussion and analysis of previously published material from the Carpathian Basin and new findings from the tell settlement Százhalombatta-Földvár in Hungary, the author of the thesis, Claes Uhn©r, describes the ways in which leaders could exercise power. Tell-building societies had relatively advanced economies. The subsistence economy, which was based on agricultural production and animal husbandry, produced a good return, and the societies were involved in regional and long-distance exchange of bronzes and other valuable craft products. “By exercising a degree of control over these parts of the economy, it was possible for leaders to finance political activities and power- exerting organisations,” says Uhn©r. He shows in his thesis that, through military power, leaders were able to control surrounding settlements from fortified tells. As the majority of these settlements were situated next to rivers and other natural transport routes, they could demand tribute from passing trade expeditions and act as intermediaries in the exchange of goods that took place in the region. In addition, a large tell was a manifestation of a successful society with a long history. This situation made it possible for leaders to use the cultural traditions of the society in ideological power strategies.

“The tells served as physical manifestations of a social system that worked well, which legitimized the social position of the elites and their right to lead. An important conclusion drawn by Uhn©r is that the sources of power could be used in strategies where they supported each other. Economic power made it possible to master military and ideological means of power. Military power was utilized to safeguard economic and ideological resources, while ideology legitimized the social system. This was largely possible because the tell settlements served as political power centers. Redistribution of staples and specialized production was attached to these sites, and they had key military and ideological significance. “By controlling tells and the activities carried out in them, leaders had an organizational advantage over the rest of the population, and others found it very difficult to build up competing power positions,” says Uhn©r. The thesis has been successfully defended.

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On the Net:

• University of Gothenburg

Developing biofuel from native perennials instead of corn in the Midwest’s rolling grasslands would better protect threatened bird populations, Michigan State University research suggests.

Federal mandates and market forces both are expected to promote rising biofuel production, MSU biologist Bruce Robertson says, but the environmental consequences of turning more acreage over to row crops for fuel are a serious concern.

Ethanol in America is chiefly made from corn, but research is focusing on how to cost-effectively process cellulosic sources such as wood, corn stalks and grasses. Perennial grasses promise low cost and energy inputs ““ planting, fertilizing, watering ““ and the new study quantifies substantial environmental benefits.

“Native perennial grasses might provide an opportunity to produce biomass in ways that are compatible with the conservation of biodiversity and important ecosystem services such as pest control,” Robertson said. “This work demonstrates that next-generation biofuel crops have potential to provide a new source of habitat for a threatened group of birds.”

With its rich variety of ecosystems, including historic prairie, southern Michigan provided a convenient place to compare bird populations in 20 sites of varying size for each of the three fuel feedstocks. Grassland birds are of special concern, Robertson said, having suffered more dramatic population losses than any other group of North American birds.

In the first such empirical comparison and the first to simultaneously study grassland bird communities across habitat scales, Robertson and colleagues found that bugs and the birds that feed on them thrive more in mixed prairie grasses than in corn. Almost twice as many species made their homes in grasses, while plots of switchgrass, a federally designated model fuel crop, fell between the two in their ability to sustain biodiversity.

The larger the plot of any type, researchers found, the greater the concentration of birds supported. But if grasslands offer conservation and biofuel opportunities, Robertson said, the biodiversity benefits could decrease as biofuel grass feedstocks are bred and cultivated for commercial uniformity.

Robertson was a research associate at MSU’s W.K. Kellogg Biological Station in Kalamazoo County during the two-year research project. Today he is an MSU adjunct entomology professor and a postdoctoral fellow at the Smithsonian Conservation Biology Institute Migratory Bird Center in Washington, D.C. His research colleagues included John A. Hannah Distinguished Professor of plant biology Douglas Schemske and research associate Liz Loomis, both at the Kellogg Biological Station; Patrick Doran of The Nature Conservancy in Lansing; and statistician J. Roy Robertson of Battle Creek.

The research was funded by the U.S. Department of Energy Great Lakes Bioenergy Research Center with support from The Nature Conservancy’s Great Lakes Fund for Partnership in Conservation Science and Economics. Results were recently published in the scientific journal GCB (Global Change Biology) Bioenergy.

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On the Net:

• Michigan State University
• GCB Bioenergy

What started with reports of unusual blackbird deaths in the southern United States earlier this week has now snowballed into multiple reports of mass bird and fish deaths from around the globe, prompting some to theorize that they may be signs of the end times.

“When the term ‘dead fish’ became a top Google search Wednesday, soaring past the likes of Lindsay Lohan and leaving Justin Bieber in its scaly wake, it looked as if the end were near,” Jill Rosen of the Los Angeles Times reported on Thursday. “That’s what everyone was saying, anyway.”

“After millions of tiny fish went belly up in Chesapeake Bay this week, much of the populace immediately dismissed the official scientific explanation (the water was just too darn cold),” she added. “What made more sense, they reasoned? The approaching apocalypse. Of course.”

The Chesapeake Bay incident, which according to the L.A. Times saw millions of dead, tiny fish wash ashore in Maryland, is the latest in a series of seemingly unexplainable mass animal deaths being reported worldwide.

As previously reported here on RedOrbit, thousands of redwing blackbirds were found dead in a small Arkansas town over the weekend, and on Tuesday, 500 additional birds were found dead in Louisiana. Arkansas officials said that testing showed no sign of disease and that the likely cause of death was “acute physical trauma”–likely caused by the birds, who have poor eyesight, becoming frightened by New Year’s Eve fireworks and colliding with objects in the dark, according to reports.

Then on Wednesday, between 50 and 100 jackdaw crows were discovered on a snow-covered street in the Swedish town of Falkoeping. According to AFP reports, the birds were initially discovered by police around midnight, and five crows were taken by experts from the National Veterinary Institute, who planned to test them for bacterial and viral infections, including swine flu.

Wednesday also saw reports surface of 200 dead birds being discovered on a highway near Tyler, Texas, as well as thousands of dead fish being discovered in Florida, some 100 tons of sardines, croaker and catfish washing up dead on the coast of Brazil, hundreds more dead fish in New Zealand, hundreds of dead robins and starlings in the Kentucky town of Gilbertsville, and an estimated 40,000 dead devil crabs in England, according to Daily Mail reports.

These incidents “are the latest in a spate of incidents which are being blamed on New Year fireworks, thunderstorms, cold weather, parasites and even poisoning,” Daily Mail reporter Wil Longbottom said in a Wednesday evening article, in which he dubbed the phenomenon “Aflockalypse.”

“The internet has been abuzz with conspiracy theories about secret government experiments being behind the deaths, or it being a sign of a looming Armageddon at the end of the Mayan calendar next year.”

Longbottom notes that tests are being carried out on the dead animals, but results of the examinations will most likely not be available for several weeks. In the meantime, panicked people around the world began wondering whether or not they could be experiencing the end times.

“George Washington University religion professor Paul Duff, who has studied the Book of Revelation and the apocalypse, didn’t seem particularly alarmed about all this when reached for comment Wednesday,” Rosen said, noting that the professor told her, “There has not been a generation that has not cried, ‘The end is near.'”

“Duff said the disturbing nature of the wildlife deaths, combined with the unanswered questions behind some of them, create the perfect climate for a doomsday plot,” the L.A. Times reporter said. “Even if all the poor birds and rotting fish portend nothing in the end, Duff has little doubt that the apocalyptically inclined will not drop their case.”

“When they expect [doomsday] to come and it doesn’t, they don’t give up that belief,” Duff told Rosen on Thursday. “They’ll just recalculate. And push [the date] forward again.”

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On the Net:

• National Veterinary Institute
• George Washington University
• Image Courtesy Adam Kumiszcza/Wikipedia

There is a lot of plastic trash floating in the Pacific Ocean, but claims that the “Great Garbage Patch” between California and Japan is twice the size of Texas are grossly exaggerated, according to an analysis by an Oregon State University scientist.

Further claims that the oceans are filled with more plastic than plankton, and that the patch has been growing tenfold each decade since the 1950s are equally misleading, pointed out Angelicque “Angel” White, an assistant professor of oceanography at Oregon State.

“There is no doubt that the amount of plastic in the world’s oceans is troubling, but this kind of exaggeration undermines the credibility of scientists,” White said. “We have data that allow us to make reasonable estimates; we don’t need the hyperbole. Given the observed concentration of plastic in the North Pacific, it is simply inaccurate to state that plastic outweighs plankton, or that we have observed an exponential increase in plastic.”

White has pored over published literature and participated in one of the few expeditions solely aimed at understanding the abundance of plastic debris and the associated impact of plastic on microbial communities. That expedition was part of research funded by the National Science Foundation through C-MORE, the Center for Microbial Oceanography: Research and Education.

The studies have shown is that if you look at the actual area of the plastic itself, rather than the entire North Pacific subtropical gyre, the hypothetically “cohesive” plastic patch is actually less than 1 percent of the geographic size of Texas.

“The amount of plastic out there isn’t trivial,” White said. “But using the highest concentrations ever reported by scientists produces a patch that is a small fraction of the state of Texas, not twice the size.”

Another way to look at it, White said, is to compare the amount of plastic found to the amount of water in which it was found. “If we were to filter the surface area of the ocean equivalent to a football field in waters having the highest concentration (of plastic) ever recorded,” she said, “the amount of plastic recovered would not even extend to the 1-inch line.”

Recent research by scientists at the Woods Hole Oceanographic Institution found that the amount of plastic, at least in the Atlantic Ocean, hasn’t increased since the mid-1980s ““ despite greater production and consumption of materials made from plastic, she pointed out.

“Are we doing a better job of preventing plastics from getting into the ocean?” White said. “Is more plastic sinking out of the surface waters? Or is it being more efficiently broken down? We just don’t know. But the data on hand simply do not suggest that “Ëœplastic patches’ have increased in size. This is certainly an unexpected conclusion, but it may in part reflect the high spatial and temporal variability of plastic concentrations in the ocean and the limited number of samples that have been collected.”

The hyperbole about plastic patches saturating the media rankles White, who says such exaggeration can drive a wedge between the public and the scientific community. One recent claim that the garbage patch is as deep as the Golden Gate Bridge is tall is completely unfounded, she said.

“Most plastics either sink or float,” White pointed out. “Plastic isn’t likely to be evenly distributed through the top 100 feet of the water column.”

White says there is growing interest in removing plastic from the ocean, but such efforts will be costly, inefficient, and may have unforeseen consequences. It would be difficult, for example, to “corral” and remove plastic particles from ocean waters without inadvertently removing phytoplankton, zooplankton, and small surface-dwelling aquatic creatures.

“These small organisms are the heartbeat of the ocean,” she said. “They are the foundation of healthy ocean food chains and immensely more abundant than plastic debris.”

The relationship between microbes and plastic is what drew White and her C-MORE colleagues to their analysis in the first place. During a recent expedition, they discovered that photosynthetic microbes were thriving on many plastic particles, in essence confirming that plastic is prime real estate for certain microbes.

White also noted that while plastic may be beneficial to some organisms, it can also be toxic. Specifically, it is well-known that plastic debris can absorb toxins such as PCB.

“On one hand, these plastics may help remove toxins from the water,” she said. “On the other hand, these same toxin-laden particles may be ingested by fish and seabirds. Plastic clearly does not belong in the ocean.”

Among other findings, which White believes should be part of the public dialogue on ocean trash:

* Calculations show that the amount of energy it would take to remove plastics from the ocean is roughly 250 times the mass of the plastic itself;

* Plastic also covers the ocean floor, particularly offshore of large population centers. A recent survey from the state of California found that 3 percent of the southern California Bight’s ocean floor was covered with plastic ““ roughly half the amount of ocean floor covered by lost fishing gear in the same location. But little, overall, is known about how much plastic has accumulated at the bottom of the ocean, and how far offshore this debris field extends;

* It is a common misperception that you can see or quantify plastic from space. There are no tropical plastic islands out there and, in fact, most of the plastic isn’t even visible from the deck of a boat;

* There are areas of the ocean largely unpolluted by plastic. A recent trawl White conducted in a remote section of water between Easter Island and Chile pulled in no plastic at all.

There are other issues with plastic, White said, including the possibility that floating debris may act as a vector for introducing invasive species into sensitive habitats.

“If there is a takeaway message, it’s that we should consider it good news that the “Ëœgarbage patch’ doesn’t seem to be as bad as advertised,” White said, “but since it would be prohibitively costly to remove the plastic, we need to focus our efforts on preventing more trash from fouling our oceans in the first place.”

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Image Caption: Larger plastic pieces can harbor microbes, both beneficial and harmful, scientists have discovered. (photo courtesy of C-MORE project)

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On the Net:

• Oregon State University
• C-MORE
• Angelicque “Angel” White