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Fair Play in the Genes

Study indicates that individuals' sense of fairness is at least partially ingrained in their DNA 


Science Image: dollar rip
 
GENES FOR FAIRNESS?  A study of identical and nonidentical twins finds that a person's sense of what is fair may be up to 40 percent determined by their genes.
If you have your parents' sense of fairness, it may not just be their influence. It may also be due to the DNA they passed on to you, according to a new study published in Proceedings of the National Academy of Sciences USA.

Researchers from the Massachusetts Institute of Technology, Stockholm School of Economics and Karolinska Institute (also in Stockholm) discovered this confluence of nature and nurture by having 324 pairs of identical twins, who share the same genetic makeup, and fraternal twins, who do not, participate in an exercise known as "the ultimatum game." Each game featured two players, one designated a proposer and the other a responder. The proposer was given a sum of money (in this experiment, roughly $15) to split however he or she chose with the responder, who could accept or decline the offer. If the responder nixed the deal, then neither player received a cut of the cash. Common sense dictates that the responder would accept anything over zero given the alternative, but previous research shows that responders typically reject offers they deemed insultingly low to punish their stingy counterparts.

Researchers determined that the average minimum the group as a whole would accept was around five bucks, or a third of the pot. They then plotted the threshold of each twin in pairs of identical and fraternal twins. Their findings: an identical twin's behavior could help predict that of his or her sibling, but not so with fraternal pairs. Researchers say the results indicate that at least 40 percent of the variation in perceiving fairness may stem from genetics. 

"If you're a fraternal twin, your brother or sister's behavior does not predict your behavior at all," says study co-author David Cesarini, a doctoral student in economics at M.I.T. The results "invite speculation that…economic behaviors and strategies are under considerable genetic influence."

Ernst Fehr, an economics professor at the University of Zurich, says this study is the first to show the heritability of altruistic punishment and notes that it could serve to "speed up efforts to find concrete genes and the mechanisms the genes are involved in that code for altruistic behaviors."

Cesarini says the research team is now probing possible genetic influences on cooperation and risk preferences.

PR

Record Low Arctic Sea Ice Confirmed

Arctic sea ice plummeted to the lowest levels seen in the last 30 years, shattering all previous record lows, scientists announced today after completing a full review of the entire melt season.

The average sea ice extent for this September (typically the month when sea ice reaches its lowest extent) was only 1.65 million square miles (4.28 million square kilometers)—23 percent lower than the previous record low set in September 2005, the National Snow and Ice Data Center (NSIDC) said.

A preliminary assessment last month indicated that Sept. 16 would be the date of minimum ice extent this year and that it was lower than the average of the last thirty years.

At the end of this melt season, which runs through the summer months, sea ice was 39 percent below the long-term average from 1979 to 2000 (the period that satellites have been keeping measurements of sea ice extent).

Ice extent reached such a low that the fabled Northwest Passage completely opened for the first time in human memory. When ship and aircraft records are taken into account, sea ice may have fallen by as much as 50 percent since the 1950s, the NSIDC said.

The melt also lasted longer this year, with the minimum date set at Sept. 16, whereas the average minimum date since 1979 is Sept. 12. Ice typically begins building with temperature declines after the minimum date.

Earth's rising temperatures are attributed as the cause of the increasing melting.

"Computer projections have consistently shown that as global temperatures rise, the sea ice cover will begin to shrink," said Mark Serreze of the NSIDC. "While a number of natural factors have certainly contributed to the overall decline of sea ice, the effects of greenhouse warming are now coming through loud and clear."

One reason the sea ice reached such a low extent this summer was it was already in a weakened state, with less total, and thinner, ice than normal.

"Thinner ice takes less energy to melt than thicker ice, so the stage was set for low levels of sea ice this summer," said Julienne Stroeve, also of the NSIDC.

Persistent high atmospheric pressures kept skies clear and sunny over the Arctic this summer, which also promoted strong melt. High winds from the weather pattern also pumped in warmer air.

Serreze says that this pattern of increasing melt does not bode well for the long-term survival of Arctic sea ice (and the animals, plants and people who depend upon it).

“The sea ice cover is in a downward spiral and may have passed the point of no return," Serreze said. "As the years go by, we are losing more and more ice in summer, and growing back less and less ice in winter. We may well see an ice-free Arctic Ocean in summer within our lifetimes.” 

Arctic sea ice reached its lowest annual extent—the absolute minimum—on September 15, 2007. This image is a composite image taken by the MODIS satellite on September 15 and 16, 2007, during a relatively clear-sky period. The Northwest Passage, through the channels of the Canadian Archpelago at bottom left, opened for the first time in human memory, this melt season. The Northern Sea Route, to the right around the coast of Siberia, remained blocked by a large mass of ice. Credit: NSIDC

Choosing the Best Coffee

When possible, look for coffee bearing as many of the certifications below as possible.

Fair Trade Certified

The "Fair Trade Certified" label is a third-party certification administered in the U.S. by TransFair USA, a member of Fairtrade Labelling Organizations International (FLO), and it means that coffee beans were purchased directly from growers or their cooperatives at a price higher than the commodity market rate. Both growers (including producer groups and cooperatives) and importers can be certified, and certification ensures that the price paid per pound of beans never falls below $0.10 more than the current market price. Currently, Fair Trade-certified growers are paid the FLO-established price of at least $1.21 per pound, $1.51 if it's certified organic (more than double the market rate). Certification also imposes some environmental-protection standards on growers, including a ban on the most hazardous pesticides such as DDT, methyl parathion and lindane (For more on these pesticides, see "The Backstory"), and the use of integrated pest management techniques, such as growing coffee under shade canopies. Fair Trade-certified importers must also provide pre-financing credits to growers when needed to help them comply with certification requirements. The higher wages allow farmers to invest in health care, education, community development and environmental stewardship.

Fair Trade Federation

Not a third-party certification, the Fair Trade Federation (FTF) is a voluntary membership organization that accepts growers as well as roasters and retailers based upon their commitment to, among other things, paying farmers at least the local minimum wage and protecting natural resources. While the FTF does not set specific environmental standards, they do encourage members to implement practices that help preserve biodiversity. Members must reapply annually and provide documentation about material sourcing and labor policies. Although not as reliable as TransFair, FTF coffee retailers and roasters pay at least the current FLO price.

Certified Organic

"Certified Organic" coffee must be grown without the use of synthetic pesticides and fertilizers on land that was free of such chemicals for three years prior to certification. To be certified organic, the farm must also utilize a sustainable crop rotation plan to prevent erosion, the depletion of soil nutrients and control for pests. The USDA's National Organic Program is the primary organic certifier in the U.S., but you may also see a USDA-accredited certifier such as Quality Assurance International, that abides by USDA's criteria.

Bird Friendly

The Smithsonian Migratory Bird Center (SMBC) certifies organic coffee as "Bird Friendly" if it is also "Shade Grown," which describes coffee grown under the rain forest canopy. The next best thing to a natural rain forest, traditional shade-grown coffee farms support many species of insects, mammals and reptiles and serve as a resting place or winter home for migratory birds. Biologists have found over 150 species of birds living in the shade of traditionally managed coffee and cacao (chocolate) plantations in Chiapas, Mexico, a number exceeded only in undisturbed tropical forests. A 2008 SMBC study found that bird-friendly farms harbored at least 20 different species of forest birds compared to less than 10 in non-bird-friendly farms. In fact, across all forest-dwelling species, Bird Friendly-certified farms had a higher degree of biodiversity than uncertified farms. Shade farms also reduce the need for pesticides by maintaining a natural balance between pests and their predators. Currently SMBC only certifies coffees from Latin America.

Rainforest Alliance Certified

Combining aspects of the certifications above, the Rainforest Alliance (RA) focuses on how farms are managed rather than how beans are traded, covering all aspects of production including environmental protection, worker rights and welfare and the interests of local communities. Certification requires that at least 40 percent of the coffee-growing plantation has to be covered in shade at all times in areas where the original natural vegetative cover is forest, which allows for wildlife preservation and a reduction of pesticides, but they do allow the use of some agrochemicals when pest-related damages would be greater than the farmer could cope with economically. They do, however, prohibit pesticides that are banned by the EPA, the EU and those that are on the Pesticide Action Network Dirty Dozen list and a few other international environmental program lists. RA-certified coffee farms must also pay workers at least the local minimum wage and prohibit the employment of children under the age of 15. While only a minimum of 30 percent certified content is required for products to display the "Rainforest Alliance Certified" label, retailers are required to state the percentage of certified content next to the label.

The Backstory

Though grown primarily by families on small farms, coffee is still the most valuable legal export commodity in the world behind petroleum, according to the World Bank. Unfortunately, booming demand for java has resulted in a massive shift away from traditional, environmentally beneficial growing methods to more damaging ones, and it's led to an overproduction glut that forces farmers to sell their beans well below the cost to grow them.

Environmental Issues

To get the highest yield possible, conventional coffee farms are situated on clear-cut land, exposed to full sun and treated with chemical fertilizers and pesticides. "Full-sun" farms have led to staggering deforestation, particularly in Latin America where numerous tropical ecosystems have disappeared or are on the verge of elimination. Deforestation has been spurred, in part, by a drop in coffee prices that led farmers to opt for growing methods that would provide them with a higher profits (see "Low Wages for Growers," below), but it's environmental damage is extreme. Habitats have been decimated, not only for indigenous wildlife, but for countless numbers of migratory birds as well. Sixty to 80 percent of bird species that inhabit forests throughout the eastern U.S. and Canada spend their winters in Latin America, and studies have found over 90 percent fewer bird species in sun coffee farms than shade farms. This, of course, says nothing of deforestation's contribution to global warming.

For birds and wildlife that do take refuge on full-sun farms, pesticides and chemical fertilizers might pose a threat. For example, endosulfan, an insecticide widely used against the coffee berry borer beetle, harms the reproductive systems of aquatic species and mammals and causes behavioral and biochemical changes in fish. Runoff from agricultural fields where endosulfan was applied has killed fish in mass quantities. Lindane, which has been used internationally as an agricultural insecticide, is very toxic to fish and other aquatic life and is believed to cause birth defects in amphibians. Still used as an insecticide in many developing countries, DDT was banned in the U.S. in 1972 in part for causing long term reproductive problems in birds and contributing to the near extinction of certain species including the bald eagle and the peregrine falcon. The non-selective insectide methyl parathion kills beneficial species, such as bees, as well as pests, is highly toxic to aquatic invertebrates, and moderately toxic to birds.

Social Issues

Worker Welfare

Sun-grown coffee is sprayed with a number of pesticides, but residues that reach the beans are mostly burned away in the roasting process and so pose little risk to consumers, according to the U.S. Food and Drug Administration. However, farmers and workers on coffee plantations aren't so lucky. Coffee trees grow primarily in the tropics of Africa and Latin America where growers pick the berries by hand. They are exposed to chemical fertilizers and pesticides daily, some of which sicken workers and increase their cancer risk. In 1996, the insecticide Miral 500 CS was recalled after one Colombian coffee plantation worker died and three others were sickened following exposure. Endosulfan has been shown to mimic the hormone estrogen and has caused estrogen-sensitive breast cancer cells to multiply in test tubes, and animal studies have found that long-term exposure causes kidney and liver damage.

Not only does sun-grown coffee require more pesticides, but it also needs more synthetic, petroleum-based nitrogen fertilizers. Synthetic fertilizers have contributed to nitrate contamination in drinking water in Costa Rica, with documented groundwater pollution exceeding World Health Organization levels in some cases. Nitrate contamination of groundwater has been associated with certain cancers, birth defects, hypertension and developmental problems in children.

Decaffeinated coffee is often preferred, especially as an after-dinner brew, but the chemical solvents used to remove most of the caffeine deserve some scrutiny. The most widely used solvents are methylene chloride and ethyl acetate, both of which can be harmful to workers. (According to the FDA, the decaffeination process leaves "infinitesimal" traces of the solvents on coffee beans, and poses no health hazards to consumers.) Methylene chloride is a suspected carcinogen and ethyl acetate may lead to skin problems. The Swiss Water Method, where beans are soaked in water, and the carbon dioxide (CO2) process, using CO2 in its supercritical state (between a liquid and a gas), are both preferable and only these methods can be used for organic coffee. Because the CO2 process is costly, plants take tremendous care to contain it, and there's little risk of its use contributing to global warming.

Low Wages for Growers

Spurred by an overproduction glut in the late 1990s, the price of coffee plummeted from about $1.50 to roughly a third of that by 2001. As a result, millions of coffee farmers have been forced to sell their beans at prices well below production costs. Currently the market price for beans is hovering around .60 to .70 cents per pound, while retailers charge as much as $11.00 a pound for the finished product.

In response to the overproduction crisis, Fair Trade certification for coffee arose to protect coffee farmers from price fluctuations and to reward those who practice sustainable agriculture, in the hopes that farmers not subjected to dramatic price drops would be less likely to resort to deforestation.

Corporate Responsibility

Responding to heightened consumer activism, a handful of corporate giants have taken meaningful steps toward a more environmentally sustainable and socially responsible coffee market. As a result of pressure from grassroots non-profits including Global Exchange and Oxfam America, in 2003 Proctor and Gamble began selling Fair Trade-certified coffees through Millstone, its gourmet coffee division, but has yet to extend the certification to its more widely available Folgers brand. To be compatible with its socially responsible image, Starbucks sells its Fair Trade-certified Café Estima blend year-round, and their Fair Trade-certified Kirkland Signature house blend is also available at Costco stores nationwide and in Canada. However, the company has yet to make Fair Trade coffee a viable option for customers by brewing it weekly in cafes, although they do state that its stores will brew a pot of Fair Trade coffee if a customer requests it. Kraft's entire Yuban coffee line is now Rainforest Alliance-certified. Sam's Club, Wal-Mart's warehouse retail chain, is one of the top three U.S. retailers of Fair Trade coffee and carries Bom Dia's Marques de Paiva organic- and Fair Trade-certified coffee, and Wal-Mart stores sell Proctor and Gamble's Millstone. Even McDonald's is carrying Fair Trade, organic Green Mountain coffee in its New England and Albany, New York, stores and Dunkin Donuts uses Fair Trade-certified espresso beans in its espresso drinks. That chain stores are beginning to carry certified beans is good news, but expansion is needed. Much wider impacts could be made, for example, if McDonald's stocked Fair Trade beans nationwide and if Dunkin Donuts used Fair Trade beans for coffee as well as espresso drinks.

Corporations can still be pushed to do more. Find out if your favorite brand of coffee carries any of the certifications above. If not, start a letter-writing campaign to the manufacturer asking them to provide ethical coffee choices


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