Marine turtles are among the most endangered species of the world ocean. For a better protection of these fascinating animals, scientists try to understand why turtles return to their birthplace in order to reproduce after rather long distance migrations.

Using molecular tools applied to turtles from the Cape Verde islands, scientists from GEOMAR Helmholtz Centre for Ocean Research Kiel in Germany found that males and females adopt different strategies: while females are very faithful to their island of birth, males appear less selective and mate at multiple locations.

Furthermore, the study published now in the “Proceedings of the Royal Society B: Biological Sciences” demonstrates that females from different islands have different immune genes, suggesting that returning home to reproduce is linked to advantages in parasite resistance. This is the first evidence ever to explain why many migratory animals show this type of behavior.

Worldwide, over 15,000 species are threatened by extinction, and the loggerhead sea turtle is no exception. Once the mysteries surrounding some of the species behavior are resolved, more effective conservation programs can be developed to facilitate their protection. The case of the loggerhead sea turtle is particularly interesting: Why do they migrate for several thousands of kilometers to eventually come back to their place of birth for reproduction after roughly 25 years?

To address this question, a group of evolutionary biologists from GEOMAR Helmholtz Centre focused on the world’s third largest nesting population of the loggerhead sea turtle which is found in the archipelago of Cape Verde. Despite the fact that the species is protected, the number of nesting turtles has been decreasing rapidly due to the slaughter of turtles for their meat, marine pollution, coastal development in nesting areas and fisheries by-catch. Hence, the loggerhead turtle has the “endangered” status on the Red List of Threatened Species.
 
The archipelago of Cape Verde is composed of numerous islands where turtles can be observed. In this study, scientists collected tiny skin samples from turtles on four different islands of the archipelago for analysis. Using multiple genetic tools, the scientists found that Cape Verdean female loggerheads only return to Cape Verde to breed but also to reproduce. “It was fascinating to demonstrate that most female turtles actually return to the exact island where they were born,” said lead author Victor Stiebens.

This outstanding behavior has some advantages for the turtles. The study found that a certain region in the turtle’s genome is responsible for fighting parasites and diseases, the so-called major histocompatibility complex. “Indeed, the study shows that turtles nesting at the most distant islands of the archipelago have different sets of these genes, providing the right genetic make-up to pass to the offspring to fight off the local parasite fauna present in that specific place,” explained senior author Christophe Eizaguirre.

At the same time, always returning to the same island may have detrimental effects for species with small population sizes since it may lead to inbreeding. In this study, the scientists were able to show that males counteract this inbreeding risk by being less selective in choosing their mating places. “Males seem to look for females over large regions of the archipelago, whereas females are more faithful to their place of birth to mate” reports Stiebens. “These gender-specific behaviors assure genetic transfer between the nesting islands but also the existence of genes needed in these local environments” says Eizaguirre.

The conclusions of the study show that returning home to reproduce gives individuals an additional advantage to fight off parasites and diseases, and may thus add a piece to the puzzle of the intriguing journey of marine turtles. “From a conservation perspective, the results suggest that it is very important to not lose any of the nesting colonies as each singular location provides important genetic adaptation for the survival of the entire population in the case of major biotic/abiotic changes in a globally changing environment,” says  Eizaguirre.


U.S. households have not
recuperated from recession


The U.S. central bank has concluded American households have recovered less than half the wealth they had before the country's deep recession in 2008 and 2009.

A regional branch of the Federal Reserve in St. Louis, Missouri, says U.S. families accumulated a net worth of $66 trillion by the end of last year. But it said that amounted to only 45 percent of the total households had amassed in 2007, in the months before the sharpest U.S. downturn since the 1930s.

The Fed said any conclusion the recession's economic damage largely has been repaired is not justified.

With U.S. stock indexes soaring in recent weeks to all-time highs, some experts concluded the country's households had recouped nearly all of the lost wealth. But the new report says stock-market gains primarily have benefited wealthy families.

It said that young people, the less educated, and black and Hispanic people lost the biggest share of their wealth during the recession. The report said their personal debt and difficulty in rebuilding have played a significant role in the country's sluggish economic recovery.

The U.S. jobless rate has been falling, and is now at 7.5 percent, but that is still high by the country's long-term standard. The country's economy, the world's largest, grew by 2.4 percent in the early months of the year.


Sequestration not seen hurting
tourism in Washington, D.C.


Tourism in Washington, D.C., was expected to be hurt by the $85 billion of federal budget cuts known as sequestration.  The White House canceled tours, while national parks and museums announced reductions in service, but, the summer tourism season is underway and most visitors are unaffected by the cutbacks.

The number of visitors coming to the National Air and Space Museum has actually increased since the sequester took effect.  The budget for the Smithsonian Institution museums that line the National Mall in Washington was reduced by $42 million, but spokesperson Linda St. Thomas says most tourist-related programs have not been affected.
 
“And so we had to take that out of maintenance and contracts.  We reduced travel.  We reduced a lot of staff activities.  We had a hiring freeze," she said. "So we did all that so that we would have less impact on tourists."

Budget cuts forced the closure of only three exhibits in all 16 Smithsonian museums.  Evening hours have been cut at the National Archives, where visitors can see the original Declaration of Independence.  The most visible effect of sequestration has been the cancellation of White House tours.  But on average, only three percent of the 18 million visitors to Washington every year go on a White House tour.

Marcus Warden, who is visiting from Britain with his family, did not know about the sequester cuts and thought that only foreigners were banned from the tours.

“But the White House tours, we would have liked to do that, but foreign nationals are not allowed to go round at the moment.  So, I do not know why that is," said Warden.

The intent behind the sequestration budget cuts was to impose a level of pain and discomfort that the public would not tolerate and therefore pressure the president and Congress to negotiate a long-term-debt reduction deal.  But David Nathanson, who came from Virginia with his daughter to visit the museums, says that strategy is not working. 

“I think it was a political tool for both parties, and I do not think it has had the impact that many people thought, and I do not think the impact has been far reaching and damaging, and for me it has been pretty transparent," he said.

He and most of the tourists visiting Washington say they are feeling no pain from the sequester budget cuts.


Obama and Bloomberg sent
letters with possible poison


The Secret Service says the White House mail screening facility has intercepted a letter that is similar to the ones sent to New York Mayor Michael Bloomberg that were laced with the deadly poison ricin.

The agency, which protects the president, announced Thursday they have turned over the letter to the FBI's Joint Terrorism Task Force for testing and investigation.  The agency says the letter was addressed to the White House.
 
Hours earlier, New York City police said two letters sent to Mayor Michael Bloomberg tested positive for ricin.

One of the letters was opened Friday at a New York mail processing facility and the other was opened Sunday at the Washington office of Mayors Against Illegal Guns - a Bloomberg-founded organization.

A police spokesman said both letters threatened the mayor and referred to his anti-gun group.  The spokesman said police officers who came in contact with the New York letter showed minor symptoms of ricin exposure.

Last month, ricin-tainted letters were sent to President Barack Obama, a U.S. senator and a Mississippi state judge.  A suspect in that case is in custody.


Radiation in space seen
as big danger on Mars trip


The U.S. space agency is relying on findings from an ongoing, unmanned mission to Mars as it shapes plans for a human mission to that planet in the mid-2030s.

As NASA's Mars Science Laboratory sped toward the Red Planet in 2011 and 2012, an instrument called the Radiation Assessment Detector measured radiation levels that a space crew could experience during the long journey.  

New findings published in the journal Science indicate a trip to Mars could subject space travelers to more radiation than NASA allows. Longstanding research shows that exposure to radiation increases a person's risk of developing cancer.

Scientists say one way to reduce radiation exposure is to develop new propulsion technologies that would shorten the time it takes to get to Mars, thereby reducing the time a person is subjected to radiation in deep space.

NASA's deputy director of advanced exploration systems, Chris Moore, says engineers are working on advanced systems that could cut a one-way trip to Mars down from about 250 days to 180 days.

"To get really fast trip times and cut down on the radiation exposure, we would probably need nuclear thermal propulsion, and we're working with the U.S. Department of Energy now to look at various types of fuel elements for these rockets," said Moore. "But it's a long-range technology development activity, and it will probably be many years before that is ready." 

Moore emphasized that nuclear thermal propulsion is part of the current plan to get humans to Mars.  

During the journey through deep space, astronauts would be exposed to two types of radiation that pose potential risks. Galactic cosmic rays are caused by supernova explosions and other high-energy events outside the solar system. Solar energetic particles are linked to solar flares and coronal mass ejections from the sun.

Eddie Semones, the space flight radiation health officer at NASA's Johnson Space Center in Houston, says this requires a two-pronged mitigation approach.

"We need to get there faster to reduce the impact of the galactic cosmic rays, but we need to have shielding, local shielding, on board to eliminate the effects of solar particle events, so it's hand-in-hand," he said.      

Semones says deployable shields are effective at reducing the effects of solar particle events because those events are low energy. But he says in order to reduce the effect of high-energy galactic cosmic rays, shields would have to be meters thick -- too thick for a spacecraft to launch successfully from Earth.

The Curiosity rover's Radiation Assessment Detector continued to take measurements after it landed on the Martian surface in August.

NASA says the medical community is using the radiation data to develop exposure limits for deep space explorers.


U.S. lawmakers want controls
on money in Trans-Pacific deal


Nearly 200 U.S. lawmakers have signed a letter urging President Barack Obama to insist on new rules against currency manipulation in a proposed trade agreement with Japan and 10 other countries in the Asia-Pacific region.
 
“As the United States continues to negotiate the Trans-Pacific Partnership, it is imperative that the agreement address currency manipulation,” the letter said, according to a copy obtained by reporters Thursday.
 
The effort is being led by a bipartisan group of lawmakers in the U.S. House of Representatives, including Democratic  Rep. Michael Michaud of Maine and Rep. John Dingell of Michigan and Republican Rep. Rick Crawford of Arkansas and Rep. Sam Graves of Missouri.
 
Lawmakers plan to send the letter, which has nearly 200 signatures, to Obama next week, a congressional aide said.
 
The United States has not pressed for rules against currency manipulation in its previous free trade deals.
 
The Obama administration hopes to finish talks on the proposed Trans-Pacific Partnership by the end of the year, and making new demands on an issue as contentious as currency could slow the negotiations.
 
However, Japan's recent entry into the negotiations has raised concerns, especially among Detroit-based automakers that  accuse Japan of deliberately pushing down the value of its yen to give Japanese auto exporters an unfair advantage.
 
In addition, many lawmakers want to send a message to China, which many believe is the worst currency manipulator, even though it is not a part of the talks.
 
“Incorporating currency provisions in the agreement will strengthen our ability to combat these unfair trade practices and help to create a level playing field for American workers, businesses, and farmers,” the lawmakers said in the letter.
 
Most Japanese brand autos sold in the United States are made in North America, rather than imported from Japan, according to Global Automakers, a group that represents Japanese, South Korean and some European auto companies.
 
In a letter earlier this month to U.S. lawmakers, the group argued against including currency provisions in the pact since it would only cover 12 countries.
 
In addition, Japan is essentially pursuing the same policy of “quantitative easing” that the United States has used to revive its economy, the Global Automakers said.
 
“If currency provisions were included in the TPP, those disciplines would also apply to U.S. policies, restricting our own economic policy options necessary to each future economic growth,” the group said.
 
The push to include currency rules in the agreement has support at the Peterson Institute for International Economics, a non-partisan think tank based in Washington which estimates currency manipulation by China and other countries has cost the United States as many as one million jobs.
 
Fred Bergsten, a senior fellow and director emeritus at the institute, has urged the United States to push for currency rules in both the Pacific agreement and in talks on a proposed agreement with the European Union which are expected to begin in July.
 
That would be a step toward forging rules covering more countries in the World Trade Organization and the International Monetary Fund, Bergsten said.


Tropical storm in Pacific kills
three in México then weakens


Tropical storm Barbara weakened to a depression as it crossed southern Mexico Thursday headed toward the Gulf of Mexico, with warnings lifted as wind speeds dropped, the U.S. National Hurricane Center said.
 
Barbara reached hurricane strength on Wednesday, hitting the southern Pacific coast near Mexico's biggest oil refinery and flooding roads, toppling trees and killing three men. It then weakened to a tropical storm as it moved inland.
 
The depression was near Mexico's Gulf coast, but was described as very ill-defined and the threat of heavy rains and flooding continued.
 
The Red Cross said the Salina Cruz refinery was operating normally. State oil monopoly Pemex said the same Wednesday but was not immediately available for comment on Thursday.
 
The depression was located around 40 miles (64 km) northwest of the port city of Coatzacoalcos in southern Mexico, with maximum sustained winds dropping to around 30 mph (48 kph), the center said.
 
It was moving northwest at 3 mph (5 kph) and was expected to turn toward the west and northwest and move near or along the Gulf coast, the center added.
 
“The center of Barbara is expected to emerge over the extreme southwestern Gulf of Mexico later today. Barbara is expected to weaken to a remnant low later today,” it said.
 
Fourteen fishermen were missing in the state of Oaxaca during the storm, local media reported in Mexico. Local emergency services said they could not confirm that information.


U.S. rushes to ease foreign fears
over modified wheat discovery


Major global importers expressed alarm over U.S. wheat supplies Thursday after the first-ever discovery of an unapproved strain of genetically modified grain in Oregon, as U.S. officials raced to contain the fallout.
 
Japan canceled a tender offer to buy U.S. western white wheat and the European Union said it would test incoming U.S. shipments and block any containing genetically modified wheat. U.S. wheat merchants did not report any cancellations of purchases Thursday, but some analysts feared a potentially damaging blow to the $8 billion export business.
 
“Unless there's a quick resolution, this is not going to be good for the export market,” said Art Liming, grain futures specialist with Citigroup.
 
The U.S. Department of Agriculture said nine investigators were collecting evidence in and around Oregon, the West Coast state where the genetically modified, or GM, wheat was found growing. A USDA spokesman said the investigators are taking witness statements, records and samples.
 
“We have increased the number of investigators throughout this month to work quickly and carefully to cover as much ground each day to determine what we are dealing with, how it got there, and where it might have gone,” he said.
 
The USDA said the modified wheat found in Oregon posed no threat to human health, and also said there was no evidence that the grain had entered the commercial supply chain.
 
Modified crops tolerate certain pesticides, allowing farmers to improve weed control and increase yields. Many consumers are wary of such food, and few countries allow imports of such cereals for direct human consumption.
 
While most of the U.S. corn and soybean crops come from genetically modified plants, no modified wheat varieties are approved for general planting in the United States or elsewhere, the USDA said. The EU has asked Monsanto, the maker of the GM wheat, for a detection method to allow its controls to be carried out.
 
Scientists said the wheat found in Oregon was a strain field-tested from 1998 to 2005 and deemed safe before St. Louis-based Monsanto withdrew it from the regulatory process. Wednesday, Monsanto said there was considerable reason to believe that the presence of its product was very limited.
 
U.S. wheat futures on the Chicago Board of Trade dipped on Thursday. CBOT wheat for July delivery closed 4 cents per bushel lower at $6.98-3/4 per bushel.
 
Asian wheat importers South Korea, China and the Philippines said they were monitoring the situation. The world's biggest wheat importer, Egypt, said it had no fears yet over supplies.
 
The wheat was discovered this spring in an Oregon field that grew winter wheat in 2012. USDA officials said that when a farmer sprayed the so-called volunteer plants with a powerful herbicide meant to kill off standard, unaltered wheat plants, some of them unexpectedly survived.