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A team of Danish researchers has shown that unchecked global warming would lead to a dramatic expansion of low-oxygen areas zones, or ‘dead zones’, in the global ocean by a factor of 10 or more.

Dead zones are low-oxygen areas in the ocean where higher life forms such as fish, crabs and clams are not able to live.

In shallow coastal regions, these zones can be caused by runoff of excess fertilizers from farming.

Whereas some coastal dead zones could be recovered by control of fertilizer usage, expanded low-oxygen areas caused by global warming will remain for thousands of years to come, adversely affecting fisheries and ocean ecosystems far into the future.

According to Professor Gary Shaffer of the Niels Bohr Institute, University of Copenhagen, who is the leader of the research team at the Danish Center for Earth System Science (DCESS), “Such expansion would lead to increased frequency and severity of fish and shellfish mortality events, for example off the west coasts of the continents like off Oregon and Chile.”

Together with senior scientists Steffen Olsen oceanographer at Danish Meteorological Institute and Jens Olaf Pepke Pedersen, physicist at National Space Institute, Technical University of Denmark, Professor Shaffer has performed projections with the newly-developed DCESS Earth System Model, projections that extend 100,000 years into the future.

“If, as in many climate model simulations, the overturning circulation of the ocean would greatly weaken in response to global warming, these oxygen minimum zones would expand much more still and invade the deep ocean,” he added.

Extreme events of ocean oxygen depletion leading to anoxia are thought to be prime candidates for explaining some of the large extinction events in Earth history including the largest such event at the end of the Permian 250 million years ago.

Furthermore, as sub-toxic zones expand, essential nutrients are stripped from the ocean by the process of denitrification.

This in turn would shift biological production in the lighted surface layers of the ocean toward plankton species that are able to fix free dissolved nitrogen.

This would then lead to large, unpredictable changes in ocean ecosystem structure and productivity, on top of other large unpredictable changes to be expected from ocean acidification.

According to Professor Shaffer, “The future of the ocean as a large food reserve would be more uncertain. Reduced fossil fuel emissions are needed over the next few generations to limit ongoing ocean oxygen depletion and acidification and their long-term adverse effects.”

Beekeepers who are battling a mysterious ailment that led to the disappearance of millions of honeybees now fear the sting of imported Australian bees that they worry could outcompete their hives and might carry a deadly parasite unseen in the United States.

The U.S. Department of Agriculture has allowed shipments of Australian bees to resume despite concerns by some of its own scientists.

Australia had been airfreighting the insects across the Pacific for four years to replace hives devastated by the perplexing colony collapse disorder. But six weeks ago the Australian government abruptly stopped the shipments, saying it could no longer be certain the country was free of a smaller, aggressive bee that has infested areas near the Great Barrier Reef, U.S. officials said.

Early this month, the USDA decided to permit the bee shipments to resume with some precautions, and the first planeloads arrived in San Francisco last Monday.

Beekeeper Ken Haff of Mandan, N.D., says he fears the foreign hives could kill off his apiary.

“We’ve got enough problems with our own bee diseases that we don’t know how to treat, and they open the border to a whole new species that could carry God knows what,” said Haff, a vice president of the American Honey Producers Association. “That’s a total slap in the face for us.”

Shad Sullivan, a bee wholesaler in California’s Central Valley, said that in the four years he has imported bees from Australia, he has found that the hearty imports outlive domestic bees that have been weakened by pesticides, pests and diseases.

“If the bees were truly carrying something that bad, I would have been the first to get it,” Sullivan said as a thick cloud of the buzzing insects flew overhead. “I just haven’t seen those kinds of devastation.”

Domestic honeybees feed on most flowering plants, and are vital pollinators for many food crops.

However, domestic bee stocks have been waning since 2004, when scientists first got reports of the puzzling illness that has claimed up to 90 percent of commercial hives and has been labeled colony collapse disorder.

That’s also the year the USDA allowed imports of Australian hives, and scientists have been investigating whether Australia was a source of a virus tied to the bee die-off.

Entomologists also fear that the aggressive bee species found near Australia’s Great Barrier Reef could carry a deadly mite, said Jeff Pettis, the USDA’s top bee scientist.

“This could be a threat worldwide, because if those bees are moving around the chances are this mite would move with it,” Pettis said. “We just don’t need another species causing problems.”

The Australian government has adopted emergency controls to quarantine and destroy the aggressive bees and has never detected that mite, according to materials provided by Chelsey Martin, counselor for public affairs at the Australian Embassy in Washington.

U.S. agriculture officials say they also are taking precautions.

Agricultural officials started sampling Australian bees last week after they were released in the Central Valley.

“Bees from Australia make great sense,” said Wayne Wehling, a senior entomologist in the USDA’s permit unit. “But we certainly don’t want to bring any economic impacts onto our honeybees that we don’t already have or introduce any new pests or disease.”

Government officials said they do not know how many Australian bees have been imported, but hive importer Sullivan estimates that he has sold 110,000 hives since 2005.

On Wednesday, a USDA inspector in a protective suit collected samples of bees at Sullivan’s operation.

“Hopefully this will ease the minds of people who have their own hives here,” said inspector John Iniguez. “We’re trusting Australia that they’re clean. Now we just want to confirm that.”

Students from the college of engineering at Virginia Tech in the US have made highly durable bricks composed of a lunar rock-like material, which one day might be used to build dwellings in colonies on the moon.

The invention won the In-Situ Lunar Resource Utilization materials and construction category award from the Pacific International Space Center for Exploration Systems (PISCES).

The team of students, under the advisement of Kathryn Logan, a professor in the materials science and engineering department, designed the brick as a potential building tool for future colonies on the moon.

Initially designed to construct a dome, the building material is composed of a lunar rock-like material mixed with powdered aluminum that can be molded into any shape.

Design work on the early-development lunar bricks was based on previous work by the college of engineering student team’s adviser Kathryn Logan, a professor of materials science and engineering and the Virginia Tech Langley Professor at the National Institute of aerospace in Hampton, Virginia.

Logan’s prior research entailed mixing powdered aluminum and ceramic materials to form armor plating for tanks funded through a department of defense contract.

“I theorized that if I could do this kind of reaction to make armor, then I could use a similar type of reaction to make construction materials for the moon,” Logan said.

Since actual lunar rock, known as regolith, is scarce, the students used volcanic ash from a deposit on Earth along with various minerals and basaltic glass, similar to rock on the lunar surface, according to Eric Faierson, a doctoral student who led the Virginia Tech team.

During initial experiments, the simulated regolith and aluminum powder were mixed and placed inside a shallow aluminum foil crucible.

A wire was inserted into the mixture, which was then heated to 2,700 degrees Fahrenheit triggering a reaction called self-propagating high-temperature synthesis (SHS), according to Logan.

The reaction caused the material to form a solid brick. A ceramic crucible was used in later experiments to form complex curved surfaces.

Once the student team had created a brick, they found that it was almost as strong as concrete under various pressure tests.

According to Faierson, one-square inch of the brick could withstand the gradual application of 2,450 pounds.

This strength would enable it to withstand an environment where gravity is a fraction of the pull on Earth.

In a new research, scientists have studied stone-handling behavior in several troops of Japanese macaques, which may shed light on the evolution of stone-tool use in early hominids.

By watching these monkeys acquire and maintain behavioral traditions from generation to generation, the scientists have gained insight into the cultural evolution of humans.

Primatologists Michael A. Huffman, Charmalie A.D. Nahallage, and Jean-Baptiste Leca from the Primate Research Institute in Kyoto, Japan, assessed social learning exhibited by these macaques during stone-handling, a behavior that has been passed down from elder to younger since it was observed in some of the troops in 1979.

Stone-handling, in this study, included rubbing and clacking stones together, pounding them onto hard surfaces, picking them up, and cuddling, carrying, pushing, rolling and throwing them.

The scientists found, for example, that an infant’s proximity to their mother had a significant impact on the development of the infant’s stone-handling abilities.

In other words, infants with mothers who frequently exhibited stone-handling behaviors spent more time with their mother, about 75 percent of their time, during the first three months of life, and they also participated in stone-handling earlier in life than the other infants.

These findings suggest that the mothers’ frequent stone-handling caught the infants’ attention, and as a result, the infants acquired the behavior more quickly than other infants.

Furthermore, the primatologists reported that the stone-handling behavior changed with each generation as individual macaques contributed their own patterns of stone-handling, such as stone-throwing.

According to the authors, “The recent emergence of a unique behavior, stone-throwing, may serve to augment the effect of intimidation displays.”

“Research on such transformation may shed light on the evolution of stone-tool use in early hominids,” they concluded.