Carbon-dating of an ancient beam from a Guatemalan temple may help end a century-long debate about the Mayan calendar, anthropologists said on Thursday.

Experts have long wrangled over how the Mayan calendar -- which leapt to global prominence last year when the superstitious said it predicted the end of the world -- correlates to the European calendar.

She walked with a knock-kneed gait, with a heel like a chimp but the upright posture of a human, and she may provide the most complete evidence yet of early man's closest ancestor, scientists said Thursday.

Two-million-year-old Australopithecus sediba's awkward strut would eventually send a modern man begging for a knee or hip replacement, but scientists are stunned at how evolution equipped her for both climbing trees and walking.

Australia is to fire the opening salvoes in a legal battle before the United Nations' highest court in June aimed at stopping Japan's whaling research program in Antarctica.

"The International Court of Justice... will hold public hearings in the case concerning whaling in the Antarctic, Australia versus Japan, from Wednesday 26 June," the Hague-based ICJ said in a statement on Thursday.

Several major companies issued a joint call Wednesday for the United States to enact legislation to battle climate change, saying that the issue was critical to their businesses.

Thirty-three firms including online retailer eBay, tech giant Intel, coffee leader Starbucks and sportswear makers Adidas, Nike, Patagonia, The North Face and Timberland called climate change a threat that required coordinated action.

Activists warned Thursday that wild populations of Southeast Asia's striking Tokay Gecko were in danger of being over-hunted for use in traditional medicine in China and other countries.

Calling the trade "colossal", wildlife trade monitoring network TRAFFIC called on authorities in the region to implement tougher regulations and limits on commerce involving the lizard, the second-largest gecko species.

A letter the British scientist who co-discovered the structure of DNA wrote to his son announcing the news sold Wednesday for a record sum of just over $6 million, Christie's said.

Elizabeth Van Bergen, a spokeswoman for the auction house in New York, said the sale "did make the new world auction record for a letter and was sold for $6,059,750."

Two Greenpeace activists dressed as polar bears boarded an oil platform in Norway on Wednesday to protest against Norwegian oil and gas group Statoil's planned drilling in the Arctic.

"No oil company in the world is prepared for Arctic conditions," said the head of Greenpeace Norway, Truls Gulowsen, one of the two activists who boarded the West Hercules platform currently stationed in Oelen in southwestern Norway.

Ma Wangzhen walks in the desert that threatens to engulf her onion farm on the edge of the ancient Chinese city of Dunhuang in China's northwest Gansu province, on October 25, 2007. Loss of land …more

Loss of land through desertification and drought costs up to five percent of world agricultural gross domestic product (AGDP), or some $450 billion (340 billion euros), every year, said a study presented at a U.N. conference Tuesday.

Fledglings of a southern African bird species threaten suicide to blackmail their parents into bringing them more food, scientists said Wednesday.

When hungry, pied babbler fledglings flutter from the nest to the ground, where predators roam, and start screeching to highlight their plight, said a study published in the British journal Proceedings of the Royal Society B.

It's been frozen, baked, suffocated and sprayed with toxins... and each time the bedbug bounces back, leaving tiny bite marks on legs or arms where it takes a blood meal.

But thanks to an unusual combination of Balkan folklore and nanoscale science, the pesky critter may have met its match.