MOTIVATIONAL SPEAKER: Speaker of the House Nancy Pelosi has taken the reins of the congressional climate change debate, becoming the face of cap-and-trade while President Obama and many fellow lawmakers are focused on health care. Now that the House climate bill has made it out of committee, Pelosi — who said earlier this year that she wasn't involved in the bill's day-to-day goings-on — has adopted a leadership role. She's divvying out markup rights to other committees, pushing for votes among conservative Democrats, and even led several U.S. legislators on a weeklong trip to China last week, primarily to discuss climate cooperation. Pelosi said yesterday she's optimistic about Chinese carbon cuts ahead of December's U.N. climate summit in Copenhagen, which is also a top motivator for the United States to pass a climate bill this year. China has already invested $12 billion in renewable energy, more than any country except Germany, and plans to double its clean-power production by 2020. (Sources: The Hill, China Daily, Green Inc.)

AIR ABERRANT: Soot particles in the air may be twice as deadly as previously thought, according to a new analysis of existing studies. The risk of having a condition that's a precursor to a heart attack increases 24 percent rather than 12 percent as particulate pollution goes up, according to the nonprofit Health Effects Institute. And in other environmental health news, researchers at the University of Louisville have linked unexplained liver disease cases with exposure to common pollutants such as lead and mercury, which were found in at least 60 percent of the 4,500 study subjects. (Sources: New York Times, United Press International)

LOGGING OUT: Two environmental groups sued the U.S. Forest Service Tuesday to stop a 3,400-acre timber sale in the Rio Grande National Forest, which sits at the Rio Grande River's headwaters. The federal lawsuit argues that the Forest Service didn't follow the National Forest Management Act as it evaluated the sale; conservationists say logging could worsen soil erosion in the forest, which is already losing trees to an outbreak of spruce budworms. The sale would yield about 8.3 million board feet of lumber worth about $562,891, according to a 2008 estimate. (Source: Denver Post)

CHARGING AHEAD: By the end of this year, Toyota will begin leasing plug-in hybrids in the United States, Japan and Europe that outgreen even the Prius, the automaker announced Wednesday. The plug-ins will be Toyota's first foray into lithium-ion batteries, which are common in laptops but still a mostly new frontier for cars. Very few will be available — Japan gets 200, and American and European drivers 150 each. (Source: Associated Press

FREE PARKING: Visitors to Yellowstone, Yosemite and 145 other national parks will get free admission on three weekends this summer, the Interior Department announced Tuesday. "During these tough economic times, our national parks provide opportunities for affordable vacations for families," Interior Secretary Ken Salazar said at a news conference at Cuyahoga Valley National Park in Ohio.  The free weekends will be: June 20-21, July 18-19 and Aug. 15-16. In addition to no-cost admission, some concessionaires will give away $5 vouchers, tours, boat rides and other extra perks. (Source: Los Angeles Times

BPA BAN: California's Senate on Tuesday barely approved a proposal that would ban bisphenol-A in baby bottles, sippy cups and other plastic food containers, setting up a confrontation in the state's Assembly as industry advocates argue that BPA's threats have been overblown. Despite more than 200 independent studies that have linked BPA to problems with brain development and behavior in young children, proponents of the chemical point out that it has been approved by dozens of regulatory agencies in the United States and Europe. (Source: L.A. Times)

IN COLD BLOOD: Some mosquitoes on the Galapagos Islands have begun feeding on reptiles instead of mammals and birds, especially marine iguanas and the iconic Galapagos tortoise. Scientists fear the bugs' new appetite for cold-blooded blood could introduce new diseases to the already-threatened Galapagos reptiles, a scenario that's increasingly common as more human visitors set foot on the islands. Mosquitoes were introduced to the Galapagos 200,000 years ago — meaning they probably weren't brought by humans, as once believed — and have adapted well,  developing the ability to breed farther inland and at higher altitudes than their mainland relatives. (Source: ScienceDaily)

Russell McLendon

(Photo: Andy Wong/AP)

Russell McLendon ( @russmclendon ) writes about humans and other wildlife.