Measuring the Universe’s 'Exit Door': For the First Time, an International Team Has Measured the Radius of a Black Hole

  

This image, created using computer models, shows how the extreme gravity of the black hole in M87 distorts the appearance of the jet near the event horizon. Part of the radiation from the jet is bent by gravity into a ring that is known as the 'shadow' of the black hole.

(Sep. 27, 2012) — The point of no return: In astronomy, it's known as a black hole -- a region in space where the pull of gravity is so strong that nothing, not even light, can escape. Black holes that can be billions of times more massive than our sun may reside at the heart of most galaxies. Such supermassive black holes are so powerful that activity at their boundaries can ripple throughout their host galaxies.

Now, an international team, led by researchers at MIT's Haystack Observatory, has for the first time measured the radius of a black hole at the center of a distant galaxy -- the closest distance at which matter can approach before being irretrievably pulled into the black hole.

The scientists linked together radio dishes in Hawaii, Arizona and California to create a telescope array called the "Event Horizon Telescope" (EHT) that can see details 2,000 times finer than what's visible to the Hubble Space Telescope. These radio dishes were trained on M87, a galaxy some 50 million light years from the Milky Way. M87 harbors a black hole 6 billion times more massive than our sun; using this array, the team observed the glow of matter near the edge of this black hole -- a region known as the "event horizon."

"Once objects fall through the event horizon, they're lost forever," says Shep Doeleman, assistant director at the MIT Haystack Observatory and research associate at the Smithsonian Astrophysical Observatory. "It's an exit door from our universe. You walk through that door, you're not coming back."

Doeleman and his colleagues have published the results of their study this week in the journal Science.

Jets at the edge of a black hole

Supermassive black holes are the most extreme objects predicted by Albert Einstein's theory of gravity -- where, according to Doeleman, "gravity completely goes haywire and crushes an enormous mass into an incredibly close space." At the edge of a black hole, the gravitational force is so strong that it pulls in everything from its surroundings. However, not everything can cross the event horizon to squeeze into a black hole. The result is a "cosmic traffic jam" in which gas and dust build up, creating a flat pancake of matter known as an accretion disk. This disk of matter orbits the black hole at nearly the speed of light, feeding the black hole a steady diet of superheated material. Over time, this disk can cause the black hole to spin in the same direction as the orbiting material.

Caught up in this spiraling flow are magnetic fields, which accelerate hot material along powerful beams above the accretion disk The resulting high-speed jet, launched by the black hole and the disk, shoots out across the galaxy, extending for hundreds of thousands of light-years. These jets can influence many galactic processes, including how fast stars form. 'Is Einstein right?'

A jet's trajectory may help scientists understand the dynamics of black holes in the region where their gravity is the dominant force. Doeleman says such an extreme environment is perfect for confirming Einstein's theory of general relativity -- today's definitive description of gravitation.

"Einstein's theories have been verified in low-gravitational field cases, like on Earth or in the solar system," Doeleman says. "But they have not been verified precisely in the only place in the universe where Einstein's theories might break down -- which is right at the edge of a black hole."

According to Einstein's theory, a black hole's mass and its spin determine how closely material can orbit before becoming unstable and falling in toward the event horizon. Because M87's jet is magnetically launched from this smallest orbit, astronomers can estimate the black hole's spin through careful measurement of the jet's size as it leaves the black hole. Until now, no telescope has had the magnifying power required for this kind of observation.

"We are now in a position to ask the question, 'Is Einstein right?'" Doeleman says. "We can identify features and signatures predicted by his theories, in this very strong gravitational field."

The team used a technique called Very Long Baseline Interferometry, or VLBI, which links data from radio dishes located thousands of miles apart. Signals from the various dishes, taken together, create a "virtual telescope" with the resolving power of a single telescope as big as the space between the disparate dishes. The technique enables scientists to view extremely precise details in faraway galaxies.

Using the technique, Doeleman and his team measured the innermost orbit of the accretion disk to be only 5.5 times the size of the black hole event horizon. According to the laws of physics, this size suggests that the accretion disk is spinning in the same direction as the black hole -- the first direct observation to confirm theories of how black holes power jets from the centers of galaxies.

The team plans to expand its telescope array, adding radio dishes in Chile, Europe, Mexico, Greenland and Antarctica, in order to obtain even more detailed pictures of black holes in the future.

Christopher Reynolds, a professor of astronomy at the University of Maryland, says the group's results provide the first observational data that will help scientists understand how a black hole's jets behave.

"The basic nature of jets is still mysterious," Reynolds says. "Many astrophysicists suspect that jets are powered by black hole spin ... but right now, these ideas are still entirely in the realm of theory. This measurement is the first step in putting these ideas on a firm observational basis."

This research was supported by the National Science Foundation.

High Dolphin Deaths in Gulf of Mexico Due to Oil Spill and Other Environmental Factors

 

The largest oil spill on open water to date and other environmental factors led to the historically high number of dolphin deaths in the Gulf of Mexico, concludes a two-year scientific study released July 19.

A team of biologists from several Gulf of Mexico institutions and the University of Central Florida in Orlando published their findings in the journal PLoS ONE.

For the past two years, scientists have been trying to figure out why there were a high number of dolphin deaths, part of what's called an "unusual mortality event" along the northern Gulf of Mexico.

Most troubling to scientists was the exceptionally high number of young dolphins that made up close to half of the 186 dolphins that washed ashore from Louisiana to western Florida from January to April 2011. The number of "perinatal" (near birth) dolphins stranded during this four-month period was six times higher than the average number of perinatal strandings in the region since 2003 and nearly double the historical percentage of all strandings.

"Unfortunately it was a 'perfect storm' that led to the dolphin deaths," said Graham Worthy, a UCF provosts distinguished professor of biology and co-author of the study. "The oil spill and cold winter of 2010 had already put significant stress on their food resources, resulting in poor body condition and depressed immune response. It appears the high volumes of cold freshwater coming from snowmelt water that pushed through Mobile Bay and Mississippi Sound in 2011 was the final blow."

The cold winter of 2010 was followed by the historic BP Deepwater Horizon disaster in April 2010, which dumped millions of gallons of oil into the Gulf of Mexico, likely disrupting the food chain. This was in the middle of the dolphins' breeding season. A sudden entry of high volumes of cold freshwater from Mobile Bay in 2011 imposed additional stress on the ecosystem and specifically on dolphins that were already in poor body condition.

"When we put the pieces together, it appears that the dolphins were likely weakened by depleted food resources, bacteria, or other factors as a result of the 2010 cold winter or oil spill, which made them susceptible to assault by the high volumes of cold freshwater coming from land in 2011 and resulted in distinct patterns in when and where they washed ashore," said Ruth Carmichael, a senior marine scientist at the Dauphin Island Sea Lab, an assistant professor of Marine Sciences at the University of South Alabama and the lead author of the study.

The majority of perinatal strandings were centered on the Mississippi-Alabama coast, adjacent to Mobile Bay, the 4th largest freshwater drainage in the U.S. The onshore movement of surface currents during the same period resulted in animals washing ashore along the stretch of coastline where freshwater discharge was most intense.

Others who contributed to the study include: William M. Graham and Stephan Howden from the University of Southern Mississippi, Stennis Space Center and Allen Aven from the Dauphin Island Sea Lab and the University of South Alabama.

Worthy is the Hubbs Professor of Marine Mammalogy. He received his PhD in 1986 from the University of Guelph in Canada and then completed post-doctoral training at the University of California at Santa Cruz, where he studied elephant seals, bottlenose dolphins and California sea lions. He spent 11 years as a faculty member in the Department of Marine Biology at Texas A&M University at Galveston and served as the State Coordinator for the Texas Marine Mammal Stranding Network.

Worthy and his team at UCF have been studying dolphin populations in the Pensacola and Choctawhatchee bays for years.

Venice Lagoon Research Indicates Rapid Climate Change in Coastal Regions

Grand Canal Venice.

Research undertaken by the University of Southampton and its associates in Venice has revealed that the sea surface temperature (SST) in coastal regions is rising as much as ten times faster than the global average of 0.13 degrees per decade.

Researchers believe that this is partly as a result of a process known as the 'urban heat island effect'; where regions experiencing rapid industrial and urban expansion produce vast amounts of heat, making the area warmer than its surroundings.

Professor Carl Amos of Ocean and Earth Sciences at the University of Southampton, will be making a speech at the Estuarine & Coastal Sciences Association's Research & Management of Transitional Waters international symposium, in Lithuania on September 27. He explains: "The urban heat island effect is a little considered problem with extreme consequences. Take London for example; the air temperature in the capital and the SST of the Thames is always warmer than it is in the rest of the UK. Similarly, in South Korea, an area which has seen rapid industrial expansion, the SST is rising at a rate of 0.26 degrees per decade -- significantly higher than the global average. Two thirds of this rise is explained by local air temperature, which is largely driven by the urban heat island effect."

The world's coastal zone occupies 18 per cent of the world's land mass and it is estimated that 1.6 billion people live in these regions world-wide. The coastal population density is three times the global average and this population is expected to increase 30 per cent by 2025, with trade and infrastructure at the coasts also increasing steadily. Research suggests that in coastal regions of high urban development, human activity is directly warming adjacent coastal waters and that this contribution to global warming at the coastal zones is equal to, or greater than, other factors such as greenhouse gasses.

Professor Amos, who is based at the National Oceanography Centre Southampton (NOCS) says: "The Marine Climate Change Impacts Partnership Report of 2006 stated that the capacity to define and predict long-term coastal changes due to human causes is 'unknown' and confidence in results is 'low'. This is a major barrier to planning for inevitable changes in coastal SST. Most of these changes at coastlines are caused by human activity, but as it is complex to consider these factors accurately, the official International Panel for Climate Change (IPCC) figures do not take these coastal 'anomalies' into account."

In Venice, with 22 million visitors annually and tourism a year-round source of income, the economy remains critically dependent on the city maintaining its status as one of the world's most desirable destinations. Southampton's research in Venice has highlighted the tension between tourism's economic benefits and environmental repercussions. Analyses of seawater temperature trends in the Venice Lagoon have suggested an increase during winter months ten times greater than that predicted globally by the IPCC -- a result directly linked to tourism.

Thousands of jobs and the Venetian economy rely on the survival of the fishing industry, which is dependent on the temperature of the coastal seawater in the Venice Lagoon. A rise in SST in the coastal zone reduces oxygen levels and displaces marine fish and associated nursery grounds, causing catastrophic fish kill phenomena. This research has helped predict the viability of clam fisheries and aquaculture habitats that serve the restaurant trade that caters for millions of tourists every year.

Professor Amos says: "The findings in Venice are the result of a 15 year partnership with the city, which are of great importance and have worldwide applications. Massive urbanisation of the coastal zones means urban heat islands represent an acute problem, particularly for the fishing industry and also for the maintenance of coastal infrastructure. The Thames, like the Venice Lagoon, is a major contributor to and casualty of the urban heat island effect. The consequences of the urban heat island effect need addressing urgently to secure the future of our coastal habitats."

 

Emerging Biotechnology : Excessive Internet Use Is Linked to Depression

Emerging Biotechnology : Excessive Internet Use Is Linked to Depression: People who spend a lot of time browsing the Internet are more likely to show depressive symptoms, according to the first large-scale stu...

Excessive Internet Use Is Linked to Depression

People who spend a lot of time browsing the Internet are more likely to show depressive symptoms, according to the first large-scale study of its kind in the West by University of Leeds psychologists.

Researchers found striking evidence that some users have developed a compulsive internet habit, whereby they replace real-life social interaction with online chat rooms and social networking sites. The results suggest that this type of addictive surfing can have a serious impact on mental health.

Lead author Dr Catriona Morrison, from the University of Leeds, said: "The internet now plays a huge part in modern life, but its benefits are accompanied by a darker side.

"While many of us use the internet to pay bills, shop and send emails, there is a small subset of the population who find it hard to control how much time they spend online, to the point where it interferes with their daily activities."

These 'internet addicts' spent proportionately more time browsing sexually gratifying websites, online gaming sites and online communities. They also had a higher incidence of moderate to severe depression than non-addicted users.

"Our research indicates that excessive internet use is associated with depression, but what we don't know is which comes first -- are depressed people drawn to the internet or does the internet cause depression?

"What is clear, is that for a small subset of people, excessive use of the internet could be a warning signal for depressive tendencies."

Incidents such as the spate of suicides among teenagers in the Welsh town of Bridgend in 2008 led many to question the extent to which social networking sites can contribute to depressive thoughts in vulnerable teenagers. In the Leeds study, young people were more likely to be internet addicted than middle-aged users, with the average age of the addicted group standing at 21 years.

"This study reinforces the public speculation that over-engaging in websites that serve to replace normal social function might be linked to psychological disorders like depression and addiction," added Dr Morrison. "We now need to consider the wider societal implications of this relationship and establish clearly the effects of excessive internet use on mental health."

 

This was the first large-scale study of Western young people to consider the relationship between internet addiction and depression. The internet use and depression levels of 1,319 people aged 16-51 were evaluated for the study, and of these, 1.2% were classed as being internet addicted. While small, this is larger than the incidence of gambling in the UK, which stands at 0.6%.

Internet Addiction: Causes at the Molecular Level

"It was shown that Internet addiction is not a figment of our imagination," says the lead author, Privatdozent Dr. Christian Montag from the Depart­ment for Differential and Biological Psychology at the University of Bonn. "Researchers and therapists are increasingly closing in on it." Over the past years, the Bonn researchers have interviewed a total of 843 people about their Internet habits. An analysis of the questionnaires shows that 132 men and women in this group exhibit problematic behavior in how they handle the online medium; all their thoughts revolve around the Internet during the day, and they feel their wellbeing is severe­ly impacted if they have to go without it.

Gene variation more frequent in Internet addicts

The researchers from the University of Bonn and the Central Institute of Mental Health in Mannheim compared the genetic makeup of the pro­blematic Internet users with that of healthy control individuals. This showed that the 132 subjects are more often carriers of a genetic variation that also plays a major role in nicotine addiction. "What we already know about the nicotinic acetylcholine receptor in the brain is that a mutation on the related gene promotes addictive behavior," explains Dr. Montag. Nicotine from tobacco fits -- just like acetylcholine, which is produced by the body -- like a key into this receptor. Both these neurotransmitters play a significant role in activating the brain's reward system. "It seems that this connection is not only essential for nicotine addiction, but also for Internet addiction," reports the Bonn psychologist.

Women more affected by this mutation

The actual mutation is on the CHRNA4 gene that changes the genetic make­up for the Alpha 4 subunit on the nicotinic acetylcholine receptor. "Within the group of subjects exhibiting problematic Internet behavior this variant occurs more frequently -- in particular, in women," says Dr. Montag. This finding will have to be validated further because numerous surveys have found that men are more prone to Internet addiction than women. The psychologist assumes, "The sex-specific genetic finding may result from a specific subgroup of Internet dependency, such as the use of social networks or such."

Better addiction diagnosis through biological markers

Dr. Montag added that studies including more subjects are required to further analyze the connection between this mutation and Internet addiction. "But the current data already shows that there are clear indications for genetic causes of Internet addiction." He added that with the mutation, a biological marker had been found that would allow to characterize online addiction from a neuro-scientific angle. "If such connections are better understood, this will also result in important indications for better therapies," says Dr. Montag.

Bioengineers Introduce 'Bi-Fi' -- The Biological 'Internet'

Bioengineers have created a biological mechanism to send genetic messages from cell to cell -- something they've nicknamed the biological Internet, or "Bi-Fi." 

(Sep. 27, 2012) — If you were a bacterium, the virus M13 might seem innocuous enough. It insinuates more than it invades, setting up shop like a freeloading houseguest, not a killer. Once inside it makes itself at home, eating your food, texting indiscriminately. Recently, however, bioengineers at Stanford University have given M13 a bit of a makeover.

The researchers, Monica Ortiz, a doctoral candidate in bioengineering, and Drew Endy, PhD, an assistant professor of bioengineering, have parasitized the parasite and harnessed M13's key attributes -- its non-lethality and its ability to package and broadcast arbitrary DNA strands -- to create what might be termed the biological Internet, or "Bi-Fi." Their findings were published online Sept. 7 in the Journal of Biological Engineering.

Using the virus, Ortiz and Endy have created a biological mechanism to send genetic messages from cell to cell. The system greatly increases the complexity and amount of data that can be communicated between cells and could lead to greater control of biological functions within cell communities. The advance could prove a boon to bioengineers looking to create complex, multicellular communities that work in concert to accomplish important biological functions.

Medium and message

M13 is a packager of genetic messages. It reproduces within its host, taking strands of DNA -- strands that engineers can control -- wrapping them up one by one and sending them out encapsulated within proteins produced by M13 that can infect other cells. Once inside the new hosts, they release the packaged DNA message.

The M13-based system is essentially a communication channel. It acts like a wireless Internet connection that enables cells to send or receive messages, but it does not care what secrets the transmitted messages contain.

"Effectively, we've separated the message from the channel. We can now send any DNA message we want to specific cells within a complex microbial community," said Ortiz, the first author of the study.

It is well-known that cells naturally use various mechanisms, including chemicals, to communicate, but such messaging can be extremely limited in both complexity and bandwidth. Simple chemical signals are typically both message and messenger -- two functions that cannot be separated.

"If your network connection is based on sugar then your messages are limited to 'more sugar,' 'less sugar,' or 'no sugar'" explained Endy.

Cells engineered with M13 can be programmed to communicate in much more complex, powerful ways than ever before. The possible messages are limited only by what can be encoded in DNA and thus can include any sort of genetic instruction: start growing, stop growing, come closer, swim away, produce insulin and so forth.

Rates and ranges

In harnessing DNA for cell-cell messaging the researchers have also greatly increased the amount of data they can transmit at any one time. In digital terms, they have increased the bit rate of their system. The largest DNA strand M13 is known to have packaged includes more than 40,000 base pairs. Base pairs, like 1s and 0s in digital encoding, are the basic building blocks of genetic data. Most genetic messages of interest in bioengineering range from several hundred to many thousand base pairs.

Ortiz was even able to broadcast her genetic messages between cells separated by a gelatinous medium at a distance of greater than 7 centimeters.

"That's very long-range communication, cellularly speaking," she said.

Down the road, the biological Internet could lead to biosynthetic factories in which huge masses of microbes collaborate to make more complicated fuels, pharmaceuticals and other useful chemicals. With improvements, the engineers say, their cell-cell communication platform might someday allow more complex three-dimensional programming of cellular systems, including the regeneration of tissue or organs.

"The ability to communicate 'arbitrary' messages is a fundamental leap -- from just a signal-and-response relationship to a true language of interaction," said Radhika Nagpal, professor of computer science at the Wyss Institute for Biologically Inspired Engineering at Harvard University, who was not involved in the research. "Orchestrating the cooperation of cells to form artificial tissues, or even artificial organisms is just one possibility. This opens a door to new biological systems and solving problems that have no direct analog in nature."

Ortiz added: "The biological Internet is in its very earliest stages. When the information Internet was first introduced in the 1970s, it would have been hard to imagine the myriad uses it sees today, so there's no telling all the places this new work might lead."

Coral Reefs May Start Dissolving When Atmospheric Carbon Dioxide Doubles

Coral reef. If carbon dioxide reaches double pre-industrial levels, coral reefs can be expected to not just stop growing, but also to begin dissolving all over the world.

Rising carbon dioxide in the atmosphere and the resulting effects on ocean water are making it increasingly difficult for coral reefs to grow, say scientists. A study to be published online March 13, 2009 in Geophysical Research Letters by researchers at the Carnegie Institution and the Hebrew University of Jerusalem warns that if carbon dioxide reaches double pre-industrial levels, coral reefs can be expected to not just stop growing, but also to begin dissolving all over the world.

The impact on reefs is a consequence of both ocean acidification caused by the absorption of carbon dioxide into seawater and rising water temperatures. Previous studies have shown that rising carbon dioxide will slow coral growth, but this is the first study to show that coral reefs can be expected to start dissolving just about everywhere in just a few decades, unless carbon dioxide emissions are cut deeply and soon.

"Globally, each second, we dump over 1000 tons of carbon dioxide into the atmosphere and, each second, about 300 tons of that carbon dioxide is going into the oceans," said co-author Ken Caldeira of the Carnegie Institution's Department of Global Ecology, testifying to the U.S. House of Representatives Subcommittee on Insular Affairs, Oceans and Wildlife of the Committee on Natural Resources on February 25, 2009. "We can say with a high degree of certainty that all of this CO₂ will make the oceans more acidic – that is simple chemistry taught to freshman college students."

The study was designed determine the impact of this acidification on coral reefs. The research team, consisting of Jacob Silverman, Caldeira, and Long Cao of the Carnegie Institution as well as Boaz Lazar and Jonathan Erez from The Hebrew University of Jerusalem, used field data from coral reefs to determine the effects of temperature and water chemistry on coral calcification rates. Armed with this information, they plugged the data into a computer model that calculated global seawater temperature and chemistry at different atmospheric levels of CO₂ ranging from the pre-industrial value of 280 ppm (parts per million) to 750 ppm. The current atmospheric concentration is over 380 ppm, and is rapidly rising due to human-caused emissions, primarily through the burning of fossil fuels.

Based on the model results for more than 9,000 reef locations, the researchers determined that at the highest concentration studied, 750 ppm, acidification of seawater would reduce calcification rates of three quarters of the world's reefs to less than 20% of pre-industrial rates. Field studies suggest that at such low rates, coral growth would not be able to keep up with dissolution and other natural as well as manmade destructive processes attacking reefs.

Prospects for reefs are even gloomier when the effects of coral bleaching are included in the model. Coral bleaching refers to the loss of symbiotic algae that are essential for healthy growth of coral colonies. Bleaching is already a widespread problem, and high temperatures are among the factors known to promote bleaching. According to their model the researchers calculated that under present conditions 30% of reefs have already undergone bleaching and that at CO₂ levels of 560 ppm (twice pre-industrial levels) the combined effects of acidification and bleaching will reduce the calcification rates of all the world's reefs by 80% or more. This lowered calcification rate will render all reefs vulnerable to dissolution, without even considering other threats to reefs, such as pollution.

"Our fossil-fueled lifestyle is killing off coral reefs," says Caldeira. "If we don't change our ways soon, in the next few decades we will destroy what took millions of years to create."

"Coral reefs may be the canary in the coal mine," he adds. "Other major pieces of our planet may be similarly threatened because we are using the atmosphere and oceans as dumps for our CO₂ pollution. We can save the reefs if we decide to treat our planet with the care it deserves. We need to power our economy with technologies that do not dump carbon dioxide into the atmosphere or oceans."

Bioeroding Sponges Are Threatening Coral Reefs

The bioeroding sponge Cliona orientalis (right) attacks live coral at the Great Barrier Reef (left).

Due to the massive production of the greenhouse gas carbon dioxide, our oceans are becoming increasingly acidic. Scientists of Senckenberg am Meer in Wilhelmshaven studied the consequences of ocean acidification on sponges that bore into calcareous materials such as coral skeletons. Results show that these sponges will profit from global changes, while coral reefs are threatened in their survival.

The study was published in the online journal PLoS ONE.

Increasing concentrations of carbon dioxide are not only changing the atmosphere, but also the oceans: Carbon dioxide reacts with water and forms carbonic acid, which acidifies the seas. The pH decreases simultaneously with this acidification, having mostly negative effects on many organisms in our oceans.

"Especially organisms that form calcareous skeletons, such as corals, will have to expend more energy in more acidic conditions," states Dr. Max Wisshak from Senckenberg am Meer in Wilhelmshaven. "In contrast -- so our hypothesis -- organisms that bioerode calcareous skeletons by biochemical etching should have an easier job in future and should thus be counted into the small circle of winners of the global change."

To test this hypothesis the team of scientists in collaboration with the Australian Institute of Marine Science and GEOMAR -- Helmholtz Centre for Oceanography in Kiel conducted elaborate experiments at the largest coral reef on earth, the Australian Great Barrier Reef, working with the bioeroding sponge Cliona orientalis. This demosponge is widely distributed, belongs to the most aggressive bioeroders, and will in future very likely contribute even more to the erosion of many coral skeletons in the Great Barrier Reef.

"We were able to confirm a clear relationship between the pH of the seawater and the bioerosion rate of these sponges," says Wisshak. "Our data predict an up to 25 percent increase of sponge bioerosion until end of this century!"

As bioeroding sponges often contribute the lion share of coral bioerosion on tropical reefs, with increasing ocean acidification the reefs will be exposed to a duplicate burden: calcification will be more difficult, and existing skeletons will be more strongly weakened by bioerosion. "This may lead to a shift from present-day positive reef growth to future negative budgets with stronger reef bioerosion. In consequence our reefs would be threatened by yet another stress factor," explains the marine geologist from Wilhelmshaven.

Testing effects of rising sea surface temperatures in the world's oceans -- another consequence of the present global change -- revealed a comparatively small influence on bioerosion rates of the sponges. What the sponges do not mind has a serious outcome for corals: Rising temperatures have a large impact on corals: Heat stress causes "bleaching" in corals, and in consequence they can die in dramatic mass mortality events.

The outcome of severe bleaching events is disastrous as reefs are home to many marine organisms and the basis of a complex food chain -- all the way up to humans.

Plant Perfumes Woo Beneficial Bugs to Their Roots

Scientists funded by the Biotechnology and Biological Sciences Research Council (BBSRC) have discovered that maize crops emit chemical signals which attract growth-promoting microbes to live amongst their roots. This is the first chemical signal that has been shown to attract beneficial bacteria to the maize root environment.

The study was led by Dr Andy Neal of Rothamsted Research in Hertfordshire and Dr Jurriaan Ton of the University of Sheffield's Department of Animal and Plant Sciences. By deepening our understanding of how cereals interact with microorganisms in the soil their research aims to contribute to ongoing efforts to increase cereal yields sustainably to feed a growing world population.

This research could be particularly useful in the fight against soil-borne pests and diseases. By breeding plants that are better at recruiting disease suppressing and growth promoting bacteria scientists hope to reduce agricultural reliance on fertilisers and pesticides.

The research is published April 24, 2012 in the open-access journal PLoS One.

Dr Andrew Neal, who co-led the research, said "We have known for a while that certain plants exude chemicals from their roots that attract other organisms to the area. In fact, the environment around a plant's roots teems with microorganisms and populations of bacterial cells can be up to 100 times denser around roots than elsewhere. Simple compounds such as sugars and organic acids are attractive to these microorganisms as they are a good source of energy; however other more complex chemicals were not known to serve as attractants because they were typically thought of as toxic.

"Now we have evidence that certain bacteria -- we studied a common soil bacterium called Pseudomonas putida -- use these chemical toxins to locate a plant's roots. The plant benefits from the presence of these bacteria because they make important nutrients like iron and phosphorus more available and help by competing against harmful bacteria around the root system."

The soil around a plant is awash with chemicals exuded by its roots. This makes it rich in nutrients but also potentially more toxic for microorganisms. The roots of young maize plants exude large quantities of chemicals called benzoxazinoids or 'BXs' which are known to play a role in helping the plant defend itself against pests above the ground in its stem and leaves. Dr Neal and Dr Ton found that a number of bacterial genes that are associated with movement responded to one of these BX chemicals, encouraging Psudomonas putida to migrate towards the plant. They also found that the presence of Psudomonas putida accelerated the breakdown of BX molecules suggesting that the bacteria have evolved the ability to detoxify the root environment, perhaps even using BX molecules as an energy source.

Dr Jurriaan Ton from the University of Sheffield co-led the research. He added "Our study has opened up exciting new opportunities for follow-up research. One interesting lead came from our analysis of the bacterial genes that were switched on in the presence of root -produced BX chemicals. This analysis suggested that the BX chemicals not only recruit the bacteria to the root surface, but they also activate processes in these bacteria that can help to suppress soil-borne diseases. This is really exciting as it would mean that the plant is not only recruiting beneficial microbes but also regulating how they behave."

He added "The next important step is to obtain a molecular blueprint of the microbial communities that are shaped by these root chemicals, and to investigate what beneficial impacts these microbes have on plant growth, plant health and soil quality."

Horticultural Hijacking: The Dark Side of Beneficial Soil Bacteria

 
Biofilm formed by soil bacteria (Bacillus subtilis) on the roots of an Arabidopsis plant

(Sep. 21, 2012) — It's a battleground down there -- in the soil where plants and bacteria dwell. Even though beneficial root bacteria come to the rescue when a plant is being attacked by pathogens, there's a dark side to the relationship between the plant and its white knight.

According to research reported by a University of Delaware scientific team in the September online edition of Plant Physiology, the most highly cited plant journal, a power struggle ensues as the plant and the "good" bacteria vie over who will control the plant's immune system.

"For the brief period when the beneficial soil bacterium Bacillus subtilis is associated with the plant, the bacterium hijacks the plant's immune system," says Harsh Bais, assistant professor of plant and soil sciences, whose laboratory group led the research at the Delaware Biotechnology Institute.

In studies of microbe-associated molecular patterns (MAMPs), a hot area of plant research, the UD team found that B. subtilis produces a small antimicrobial protein that suppresses the root defense response momentarily in the lab plant Arabidopsis.

"It's the first time we've shown classically how suppression by a benign bacteria works," Bais says. "There are shades of gray -- the bacteria that we view as beneficial don't always work toward helping plants."

In the past, Bais' lab has shown that plants under aerial attack send an SOS message, through secretions of the chemical compound malate, to recruit the beneficial B. subtilis to come help.

In more recent work, Bais and his collaborators showed that MAMP perception of pathogens at the leaf level could trigger a similar response in plants. Through an intraplant, long-distance signaling, from root to shoot, beneficial bacteria are recruited to forge a system-wide defense, boosting the plant's immune system, the team demonstrated. In that study, the Bais team also questioned the overall tradeoffs involved in plants that are associated with so-called beneficial microbes.

In the latest work, involving the testing of more than 1,000 plants, the researchers shed more light on the relationship. They show that B. subtilis uses a secreted peptide to suppress the immune response in plants. It is known that plants synthesize several antimicrobial compounds to ward off bacteria, Bais says.

The team also shows that when plant leaves were treated with a foliar MAMP -- flagellin, a structural protein in the flagellum, the tail-like appendage that bacteria use like a propeller -- it triggered the recruitment of beneficial bacteria to the plant roots.

"The ability of beneficial bacteria to suppress plant immunity may facilitate efficient colonization of rhizobacteria on the roots," Bais says. Rhizobacteria form an important symbiotic relationship with the plant, fostering its growth by converting nitrogen in the air into a nutrient form the plant can use.

"We don't know how long beneficial bacteria could suppress the plant immune response, but we do know there is a very strong warfare under way underground," Bais says, noting that his lab is continuing to explore these interesting questions. "We are just beginning to understand this interaction between plants and beneficial soil bacteria."

The lead author of the research article was Venkatachalam Lakshmanan, a postdoctoral researcher in the Department of Plant and Soil Sciences; Sherry Kitto, professor of plant and soil sciences; Jeffrey Caplan, associate director of UD's Bio-Imaging Center; Yu-Sung Wu, director of the Protein Production Facility; Daniel B. Kearns, associate professor in the Department of Biology at Indiana University; and Yi-Huang Hsueh , of the Graduate School of Biotechnology and Bioengineering at Yuan Ze University, Taiwan.

The research was supported by grants from the National Science Foundation.

Oral Bacteria May Signal Pancreatic Cancer Risk

Possible clue to a hard-to-diagnose cancer. Human pancreatic tumor cells stained and magnified 400 times. Research suggests a strong link, possibly predictive, between pancreatic cancer and levels of antibodies to certain oral bacteria. 


Pancreatic cancer is highly lethal and difficult to detect early. In a new study, researchers report that people who had high levels of antibodies for an infectious oral bacterium turned out to have double the risk for developing the cancer. High antibody levels for harmless oral bacteria, meanwhile, predicted a reduced pancreatic cancer risk. 

A new study finds significant associations between antibodies for multiple oral bacteria and the risk of pancreatic cancer, adding support for the emerging idea that the ostensibly distant medical conditions are related.

The study of blood samples from more than 800 European adults, published in the journal Gut, found that high antibody levels for one of the more infectious periodontal bacterium strains of Porphyromonas gingivalis were associated with a two-fold risk for pancreatic cancer. Meanwhile, study subjects with high levels of antibodies for some kinds of harmless "commensal" oral bacteria were associated with a 45-percent lower risk of pancreatic cancer.

"The relative increase in risk from smoking is not much bigger than two," said Brown University epidemiologist Dominique Michaud, the paper's corresponding author. "If this is a real effect size of two, then potential impact of this finding is really significant."

Pancreatic cancer, which is difficult to detect and kills most patients within six months of diagnosis, is responsible for 40,000 deaths a year in the United States.

Several researchers, including Michaud, have found previous links between periodontal disease and pancreatic cancer. The Gut paper is the first study to test whether antibodies for oral bacteria are indicators of pancreatic cancer risk and the first study to associate the immune response to commensal bacteria with pancreatic cancer risk. The physiological mechanism linking oral bacteria and pancreatic cancer remains unknown, but the study strengthens the suggestion that there is one.

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"This is not an established risk factor," said Michaud, who is also co-lead author with Jacques Izard, of the Forsyth Institute and Harvard University. "But I feel more confident that there is something going on. It's something we need to understand better."

Izard, a microbiologist, said the importance of bacteria in cancer is growing. "The impact of immune defense against both commensals and pathogenic bacteria undeniably plays a role," he said. "We need to further investigate the importance of bacteria in pancreatic cancer beyond the associated risk."

Prospective, controlled study

To conduct their research, Michaud and Izard drew on medical records and preserved blood samples collected by the Imperial College-led European Prospective Investigation into Cancer and Nutrition Study, a massive dataset of more than 500,000 adults in 10 countries. Detailed health histories and blood samples are available from more than 380,000 of the participants.

From that population, the researchers found 405 people who developed pancreatic cancer, but no other cancer, and who had blood samples available. The researchers also selected 416 demographically similar people who did not develop pancreatic cancer for comparison.

The researchers blinded themselves to which samples came from cancer patients and which didn't during their analysis of the blood, which consisted of measuring antibody concentrations for 25 pathogenic and commensal oral bacteria. In their study design and analysis they controlled for smoking, diabetes, body mass index, and other risk factors.

An important element of the study design was that date of the blood samples preceded the diagnosis of pancreatic cancer by as much as a decade, meaning that the significant difference in antibody levels were likely not a result of cancer.

Instead, the underlying mechanisms that link Porphyromonas gingivalis to pancreatic cancer could be causal, Michaud said, although much more research is needed to understand this association.

Meanwhile, the researchers speculate, the association of high levels of antibodies for commensal bacteria and pancreatic cancer, may indicate an innate, highly active immune response that is protective against cancer.

"Genetic determinants of immune surveillance clearly play a critical role in pancreatic cancer development," the authors wrote. "Consequently, it is plausible that elevated levels of antibodies to oral bacteria in individuals serve as a marker for a genetically stronger immune response, providing protection against carcinogenesis."

Michaud, who studies cancer risk factors generally, continues to investigate the association between oral bacteria and pancreatic cancer in collaboration with Izard.

The National Cancer Institute was the primary funder of the study.

Shrinking Snow Depth On Arctic Sea Ice Threatens Ringed Seal Habitat

A ringed seal peaks out from its snow cave. 


As sea ice in the Arctic continues to shrink during this century, more than two thirds of the area with sufficient snow cover for ringed seals to reproduce also will disappear, challenging their survival, scientists report in a new study. 

The ringed seal, currently under consideration for threatened species listing, builds caves to rear its young in snow drifts on sea ice. Snow depths must be on average at least 20 centimeters, or 8 inches, to enable drifts deep enough to support the caves.

"It's an absolute condition they need," said Cecilia Bitz, an associate professor of atmospheric sciences at the University of Washington. She's a co-author of the study, published in the journal Geophysical Research Letters.

But without sea ice, the platform that allows the snow to pile up disappears, ultimately reducing the area where the seals can raise their pups.

Bitz typically focuses on studying the area and thickness of sea ice. "But when a seal biologist telephoned and asked what our climate models predict for snow depth on the ice, I said, 'I have no idea,'" she said. "We had never looked."

That biologist was co-author Brendan Kelly of the National Science Foundation and he was curious about the snow depth trend because he was contributing to a governmental report in response to the petition to list the seals as threatened.

The researchers, including lead author and UW atmospheric sciences graduate student Paul Hezel, found that snowfall patterns will change during this century but the most important factor in determining snow depth on the ice will be the disappearance of the sea ice.

"The snowfall rate increases slightly in the middle of winter by the end of the century," Hezel said. However, at the same time sea ice is expected to start forming later in the year than it does now. The slightly heavier snowfall in the winter won't compensate for the fact that in the fall -- which is also when it snows the heaviest -- snow will drop into the ocean instead of piling up on the ice.

The researchers anticipate that the area of the Arctic that accumulates at least 20 centimeters of snow will decrease by almost 70 percent this century. With insufficient snow depth, caves won't hold up.

Other climate changes threaten those caves, too. For instance, the snow will melt earlier in the year than it does now, so it's possible the caves won't last until the young seals are old enough to venture out on their own. In addition, more precipitation will fall as rain, which soaks into the snow and can cause caves to collapse.

The research is important for more than just the ringed seals. "There are many other reasons to study snow cover," Hezel said. "It has a huge thermodynamic impact on the thickness of the ice."

Snow on sea ice in fall and winter acts like a blanket that slows the release of heat from the relatively warm ocean into the atmosphere. That means deeper snow tempers sea ice growth.

 

In the spring, snow has a different impact on the ice. Since snow is more reflective than ice, it creates a cooling effect on the surface. "So the presence of snow helps sustain the icepack into spring time," Hezel said.

To produce the study, the scientists examined 10 different climate models, looking at historic and future changes of things like sea ice area, precipitation, snowfall and snow depth on sea ice. The resulting prediction for declining snow depth on sea ice this century agreed across all of the models.

The new research comes too late to be cited in the report about ringed seals that was written by the National Oceanic and Atmospheric Administration in response to the petition to list the ringed seal as threatened. However, it confirms results that were based on a single model that Bitz provided for the report two years ago. NOAA expects to issue its final decision soon.

The UW scientists on this study were funded by the Office of Naval Research.

Your Memory Is Like the Telephone Game, Altered With Each Retelling

Remember the telephone game where people take turns whispering a message into the ear of the next person in line? By the time the last person speaks it out loud, the message has radically changed. It's been altered with each retelling. Turns out your memory is a lot like the telephone game, according to a new Northwestern Medicine study.  

(Sep. 19, 2012) — Remember the telephone game where people take turns whispering a message into the ear of the next person in line? By the time the last person speaks it out loud, the message has radically changed. It's been altered with each retelling. 

Turns out your memory is a lot like the telephone game, according to a new Northwestern Medicine study.

Every time you remember an event from the past, your brain networks change in ways that can alter the later recall of the event. Thus, the next time you remember it, you might recall not the original event but what you remembered the previous time. The Northwestern study is the first to show this.

"A memory is not simply an image produced by time traveling back to the original event -- it can be an image that is somewhat distorted because of the prior times you remembered it," said Donna Bridge, a postdoctoral fellow at Northwestern University Feinberg School of Medicine and lead author of the paper on the study recently published in the Journal of Neuroscience. "Your memory of an event can grow less precise even to the point of being totally false with each retrieval."

Bridge did the research while she was a doctoral student in lab of Ken Paller, a professor of psychology at Northwestern in the Weinberg College of Arts and Sciences.

The findings have implications for witnesses giving testimony in criminal trials, Bridge noted.

"Maybe a witness remembers something fairly accurately the first time because his memories aren't that distorted," she said. "After that it keeps going downhill."

The published study reports on Bridge's work with 12 participants, but she has run several variations of the study with a total of 70 people. "Every single person has shown this effect," she said. "It's really huge."

"When someone tells me they are sure they remember exactly the way something happened, I just laugh," Bridge said.

The reason for the distortion, Bridge said, is the fact that human memories are always adapting.

"Memories aren't static," she noted. "If you remember something in the context of a new environment and time, or if you are even in a different mood, your memories might integrate the new information."

For the study, people were asked to recall the location of objects on a grid in three sessions over three consecutive days. On the first day during a two-hour session, participants learned a series of 180 unique object-location associations on a computer screen. The next day in session two, participants were given a recall test in which they viewed a subset of those objects individually in a central location on the grid and were asked to move them to their original location. Then the following day in session three, participants returned for a final recall test.

The results showed improved recall accuracy on the final test for objects that were tested on day two compared to those not tested on day two. However, people never recalled exactly the right location. Most importantly, in session three they tended to place the object closer to the incorrect location they recalled during day two rather than the correct location from day one.

"Our findings show that incorrect recollection of the object's location on day two influenced how people remembered the object's location on day three," Bridge explained. "Retrieving the memory didn't simply reinforce the original association. Rather, it altered memory storage to reinforce the location that was recalled at session two."

Bridge's findings also were supported when she measured participants' neural signals --the electrical activity of the brain -- during session two. She wanted to see if the neural signals during session two predicted anything about how people remembered the object's location during session three.

The results revealed a particular electrical signal when people were recalling an object location during session two. This signal was greater when -- the next day -- the object was placed close to that location recalled during session two. When the electrical signal was weaker, recall of the object location was likely to be less distorted.

"The strong signal seems to indicate that a new memory was being laid down," Bridge said, "and the new memory caused a bias to make the same mistake again."

"This study shows how memories normally change over time, sometimes becoming distorted," Paller noted. "When you think back to an event that happened to you long ago -- say your first day at school -- you actually may be recalling information you retrieved about that event at some later time, not the original event."

The research was supported by National Science Foundation grant BCS1025697 and National Institute of Neurological Disorders and Stroke of the National Institutes of Health grant T32 NS047987.

Stop Diabetes With Insulin Tablets?

(Sep. 19, 2012) — Could a capsule of insulin crystals a day stop the development of type 1 diabetes? There are indications that this could be the case. In the international TrialNet study, which follows relatives of individuals with type 1 diabetes, researchers are investigating whether oral insulin could prevent or delay the disease. 

Type 1 diabetes is the autoimmune form of diabetes, in which the patients' insulin-producing beta cells are destroyed by their own immune system. "We know that if a person has two autoantibodies and one of them is against insulin, there is a 50 per cent risk that they will develop type 1 diabetes within five years. It doesn't matter how old you are," says Åke Lernmark, Professor of Experimental Diabetes Research at Lund University in Sweden.

"There are indications that oral insulin may prevent or delay the clinical onset of type 1 diabetes among individuals with autoantibodies against insulin, who are thus in the risk zone," says Åke Lernmark, who will be initiating and coordinating the Swedish TrialNet study.

Åke Lernmark refers to a study presented earlier in the year by American and Canadian researchers. In the study, which ran from 1994 to 2003, participants with relatives who had type 1 diabetes and at least two autoantibodies, one of which against insulin, took either oral insulin or placebo capsules containing an inactive substance. At first, the results were a disappointment. Just as many people in the treatment group became ill as in the placebo group.

"However, the subsequent analyses showed something different. Among those who had high levels of insulin autoantibodies at the start of the study, the oral insulin had an effect and the development of type 1 diabetes was delayed. The delaying effect lasted for as long as the participants took the insulin," says Åke Lernmark, adding that those who are now being recruited for the Swedish TrialNet study with oral insulin also have high levels of autoantibodies against insulin.

No one knows how oral insulin might stop type 1 diabetes. However, Åke Lernmark believes a possible explanation could be that the immune system becomes accustomed to the low daily doses of insulin in the gastrointestinal tract. The insulin is not perceived as a foreign substance to be rejected by the immune system.

This line of reasoning is the same as for desensitisation for allergies, in which the dose of the substance that provokes the allergy is gradually increased.

The oral insulin study will run for several years and is open to all those who meet the requirements and are aged between 3 and 45.

Surprise Shrimp Under Antarctic Ice

 
Lyssianasid amphipod found beneath Antarctica's Ross Ice Shelf. (Credit: NASA) 


At a depth of 600 feet beneath the West Antarctic ice sheet, a small shrimp-like creature managed to brighten up an otherwise gray polar day in late November 2009.

This critter is a three-inch long Lyssianasid amphipod found beneath the Ross Ice Shelf, about 12.5 miles away from open water.

NASA scientists were using a borehole camera to look back up towards the ice surface when they spotted this pinkish-orange creature swimming beneath the ice.

West Antarctic Ice Sheet Could Become Unstable as World Warms

 
Airborne view of the Pine Island glacier, Antarctica. 


A new study examines how ice sheets, such as the West Antarctic Ice Sheet, could become unstable as the world warms. 

The team from Oxford University and Cambridge University developed a model to explore how changes in the 'grounding line' -- where an ice sheet floats free from its base of rock or sediment -- could lead to the disintegration of ice sheets and result in a significant rise in global sea level.

 

'The volume of ice locked up in the West Antarctic Ice Sheet is equivalent to a sea level rise of around 3.3 metres,' said Dr Richard Katz of Oxford University's Department of Earth Sciences, an author of the report. 'Our model shows how instability in the grounding line, caused by gradual climatic changes, has the potential to reach a 'tipping point' where disintegration of the ice sheet could occur.'

 

At the moment the model -- that uniquely takes into account the three dimensional shape of ice sheets -- is still fairly simple, but the researchers hope to eventually include more detail on how ice sheets interact with their base slopes and show the behaviour of individual ice streams.

When the team applied their theoretical and mathematical model to the West Antarctic Ice Sheet they found that, contrary to earlier assessments, a scenario which would see instability grow as the grounding line recedes was likely. In the case of the Pine Island Glacier it may already be occurring.

'Global climate models often assume that, as the world warms, ice sheets will melt at a steady rate, leading to gradual rises in sea level -- but ice sheets are much more complex structures than this,' said Dr Katz. 'We need to do a lot more work to build better models of how ice sheets behave in the real world. Only then can we start to predict how this behaviour might change in the future as the climate changes.'

A report of the research, 'Stability of ice sheet grounding lines', is published in Proceedings of the Royal Society A. The research was conducted by Dr Richard Katz of Oxford University's Department of Earth Sciences and Professor M Grae Worster of Cambridge University's Institute of Theoretical Geophysics.

Warming Ocean Could Start Big Shift of Antarctic Ice

(Sep. 19, 2012) — Fast-flowing and narrow glaciers have the potential to trigger massive changes in the Antarctic ice sheet and contribute to rapid ice-sheet decay and sea-level rise, a new study has found.

Research results published in the journal Proceedings of the National Academy of Sciences reveal in more detail than ever before how warming waters in the Southern Ocean are connected intimately with the movement of massive ice-sheets deep in the Antarctic interior.

"It has long been known that narrow glaciers on the edge of the Antarctica act as discrete arteries termed ice streams, draining the interior of the ice sheet," says Dr Chris Fogwill, an author of the study and an ARC Future Fellow with the UNSW Climate Change Research Centre.

"However, our results have confirmed recent observations suggesting that ocean warming can trigger increased flow of ice through these narrow corridors. This can cause inland sectors of the ice-sheet -- some larger than the state of Victoria -- to become thinner and flow faster."

The researchers, led by Dr Nicholas Golledge from Victoria University of Wellington, New Zealand, tested high-resolution model simulations against reconstructions of the Antarctic ice sheet from 20,000 years ago, during the last glacial maximum.

They used a new model, capable of resolving responses to ice-streams and other fine- scale dynamic features that interact over the entire ice sheet. This had not previously been possible with existing models. They then used this data to analyze the effects of a warming ocean over time.

The results showed that while glacier acceleration triggered by ocean warming is relatively localized, the extent of the resultant ice-sheet thinning is far more widespread. This observation is particularly important in light of recently observed dynamic changes at the margins of Antarctica. It also highlighted areas that are more susceptible than others to changes in ocean temperatures.

The glaciers that responded most rapidly to warming oceans were found in the Weddell Sea, the Admundsen Sea, the central Ross Sea and in the Amery Trough.

The finding is important because of the enormous scale and potential impact the Antarctic ice sheets could have on sea-level rise if they shift rapidly, says Fogwill. "To get a sense of the scale, the Antarctic ice sheet is 3km deep -- three times the height of the Blue Mountains in many areas -- and it extends across an area that is equivalent to the distance between Perth and Sydney.

"Despite its potential impact, Antarctica's effect on future sea level was not fully included in the last IPCC report because there was insufficient information about the behavior of the ice sheet. This research changes that. This new, high-resolution modelling approach will be critical to improving future predictions of Antarctica's contribution to sea level over the coming century and beyond."

Devastating Red Alga Discovered Creeping North to Maine

 
Shoals Marine Lab research student Hannah Hume examines a specimen of the invasive red algae Heterosiphonia japonica off Appledore Island, Maine, shgortly after it was first detected in 2011. Researchers at the lab have confirmed the algae has invaded the coastal waters off New Hampshire and Maine. Shoals Lab is operated jointly by Cornell University and the University of New Hampshire.

The shores of Appledore Island, Maine -- just six miles from the New Hampshire coast -- are being invaded by an aggressive red algae that can foul popular tourist beaches and damage vital local fisheries

The seaweed, Heterosiphonia japonica, is a native to Japan and has not been reported elsewhere in Maine to date. The brownish-red stringy plant was first spotted underwater on Appledore in 2011 by undergraduates in the Shoals Marine Lab Underwater Research class. By this summer most of the studied intertidal transects on the island -- permanent sites between the high- and low-tide lines -- contained Heterosiphonia.

The alga grows in the water along the shoreline, then detaches and creates vast, decaying piles in the intertidal zone along the shore. In some locations along the Atlantic coast, Heterosiphonia has covered beaches and threatened tourism with its foul odor. Biologists are also concerned that this seaweed may out-compete native plants, overwhelming local ecosystems and the commercial fisheries they support.

Researchers believe this species was transported to the Atlantic Coast on boat hulls or by shellfish aquaculture. It was first discovered in southern New England on Rhode Island's eastern seaboard in 2009.

So far, experts at the Lab -- which is jointly supported by Cornell University and the University of New Hampshire -- are cautious and say the impact of the red algae this far north has yet to be fully felt.