WHAT LIES BENEATH: Ice began to spread across Antarctica 34 million years ago, eventually burying the landscape — including its towering Gamburtsev mountains — beneath more than a mile of frozen water. Scientists have now mapped out a section of these Antarctic "ghost alps" and determined the point where they believe the continent's famed ice sheet first began forming. By driving around in trains of caterpillar tractors and sending radar "pings" down through the ice, the research team created a map of the buried mountains and realized that, given their high altitude and distance from the coast, they were the most likely place for Antarctica's first glaciers to form. This sheds light on the importance of Antarctica's ice sheet to the world at large — despite many swings in Earth's climate since the ice sheet formed, it hasn't changed in 14 million years. If it all melted, it would raise sea levels by nearly 200 feet. "The worrying thing," says one of the researchers, "is that we seem to be going back to carbon dioxide concentrations consistent with there being a lot less ice around." (Sources: New ScientistAgence France-Presse, Science News, Scientific American, BBC News)

SARDINISTAS: Sometime in the mid-20th century, sardines became almost a joke food, like fruitcakes or Spam. But they're one of the most environmentally friendly fish you can eat, and a ragtag crew of "Sardinistas" in Monterey Bay, Calif., is fighting to restore the fish's good name. Sardines are harvested sustainably in California's Cannery Row, and they're also healthier than many other fish — since they're small and eat plants, they have lower levels of mercury. (Source: Washington Post)

FORGOTTEN FOSSILS: Clean energy investments surpassed fossil fuel investments last year for the first time, according to U.N. figures released Wednesday. Renewable technologies such as wind and solar power attracted $140 billion, compared with $110 billion for electricity generated by coal and natural gas. The surge was driven largely by developing countries catching up to the West — China and India led the charge, and countries such as Kenya and Angola helped spread green power to new geographical areas. (Source: Guardian)

METEORIC RISE: Life on Earth may not have begun entirely on Earth, an idea scientists have batted around for years. Now researchers at England's Imperial College have suggested specifically when and how Earth received its first shipment of the necessary ingredients for life: A torrential downpour of meteorites about 4 billion years ago, known as the Late Heavy Bombardment, may have carried in as many as 10 billion tons of water vapor and carbon dioxide. "It is fair to say that the amount delivered in this bombardment alone was enough to kick-start the Earth on its way to habitability," the study author tells the LA Times. Mars likely received the same bombardment, but without Earth's molten iron core — which provides its strong magnetic field — the red planet was also bombarded by deadly solar radiation. (Source: Los Angeles Times)

HURRICANE WALL: Houston, we have a solution. Or at least that's what proponents of the Gulf Coast city's "Ike Dike" are saying. Entering the first hurricane season after Houston was devastated by Hurricane Ike, a state commission on disaster preparedness has suggested building a 17-foot-high wall spanning the narrow entrance to Galveston Bay with 1,000-foot-long floodgates. The gates would stay open in good weather, but could be swung shut to block storm surges from an approaching hurricane. The idea has quickly become popular, surprising even members of the commission that proposed it, but environmentalists worry it could damage the bay's fragile ecosystem, and one hurricane expert even says it could actually trap floodwaters inside the bay under certain conditions. (Source: Wall Street Journal)

JAPAN'S NEXT TOP MODEL: May be the Toyota Prius. The gas-electric hybrid was Japan's No. 1 selling vehicle in May, the first time it's managed to claim the top spot — and that's the top overall spot, not just the top hybrid. It dethroned another hybrid, the new Honda Insight, which fell to third. It was the second straight month that a hybrid led Japanese auto sales, spurred largely by a government tax break for more fuel-efficient cars that began in April. (Source: Associated Press)

THE ANTI-TESLA: Electric-car startup Miles EV will begin selling an all-electric, four-door sedan at the end of 2010 under the brand name Coda Automotive, reports Business Insider, which calls the Coda the "anti-Tesla." That's because it eschews its fellow EV startup's flashiness for an intentionally bland car that's aimed at making electric vehicles mainstream. The Coda will cost $45,000 before tax breaks, and its battery will get 100 miles per charge and takes six hours to charge. (Source: Business Insider via Huffington Post

WORLD ENVIRONMENT DAY: Is tomorrow, and Mexico will host the U.N.-sponsored event, which began in 1972 and is celebrated annually on June 5. But Greenpeace is arguing that the host country doesn't live up to the ideals of Friday's festivities, accusing it of "systematically destroying ecosystems with environment policies which do not stop deforestation." Mexico is fifth in the world for biodiversity but also fifth in deforestation, losing almost 1.5 million acres of trees each year, and Greenpeace says its tourism practices are worsening the problem. To Mexico's credit, however, it has also planted 537 million trees and is a "leading partner" in a project to plant 7 billion trees worldwide by the end of 2009, according to the U.N. Environment Program. (Sources: UNEPAFP)

Russell McLendon

(Photo: Charles Hanley/AP)

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