Los Angeles County bans plastic bags in unincorporated areas.
The hormone-disrupting chemical BPA is found on half of all cash register receipts and nearly all dollar bills.
Doubling the level of BPA in women's blood, researchers find, halves the percentage of eggs that fertilize normally in vitro.
Pregnant women who use cell phones are more likely to have disobedient children.
Children who live close to freeways are twice as likely to be autistic.
For the third time, the EPA puts off strengthening standards for ground-level ozone.
There's not enough ozone in the upper atmosphere, so whales in the Gulf of California are getting sunburned.
Thirty-five pilot whales beach themselves and die on an island off Donegal, Ireland.
Many beached dolphins turn out to be deaf.
Shark finning—slicing the fins off sharks for use in soup—is banned in U.S. territorial waters.
White ibis exposed to mercury are more likely to be gay.
Scientists discover an all-female species of lizard in India that reproduces by cloning.
A pair of endangered short-tailed albatross, once thought extinct, has started nesting on the U.S. territory of Midway Atoll.
South Korea is building a 500-turbine, 2,500-megawatt offshore wind farm, more than twice the size of China's 1,000-megawatt Bohai Bay farm.
In the United States, low prices for natural gas scuttle or delay many wind farms and solar installations.
The International Energy Agency announces that the world hit "peak oil" in 2006, with production from current fields expected to drop sharply in the coming decades.
California regulators OK a new carcinogenic pesticide for strawberries to replace the old carcinogenic pesticide they outlawed.
The Obama administration sets aside 187,000 square miles of Alaska—much of it sea ice—as critical habitat for polar bears.
Catastrophic floods put half of the West African country of Benin and much of northeastern Australia underwater.
Endangered mountain gorillas in central Africa make a dramatic recovery, with one of two populations increasing by 26 percent since 2003.
Half the incoming Republican members of Congress do not believe that global warming is real, or that, if it is, it's caused by human activity.
California's state air board approves a cap-and-trade system to reduce greenhouse gases.
International climate talks in Cancun, Mexico, end with only very modest agreements on reducing CO2 emissions.
The EPA begins a two-year process to regulate carbon emissions from industrial sources, including old oil refineries and coal-fired power plants that were exempted under the Clean Air Act.
World carbon emissions in 2010 are expected to be the highest in history.
On New Year's Eve in Arkansas, more than 5,000 red-winged blackbirds fall dead from the sky. —Paul Rauber
This article has been corrected subsequent to publication.
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