Poachers have killed nearly half of Mozambique's elephants for their ivory in the past five years, the U.S. based Wildlife Conservation Society said Tuesday.

A Mozambique government-backed survey showed a dramatic 48 percent decline in elephant numbers from just over 20,000 to an estimated 10,300, the WCS said in a statement.

The United Arab Emirates on Monday laid out a strategic framework for a newly created space agency that aims to integrate various arms of the Gulf federation's burgeoning space industry.

The seven-state federation, perhaps best known for its oil wealth and extravagant attractions like Dubai's palm-shaped islands and the record-breaking Burj Khalifa skyscraper, is fast establishing itself as the Arab world's leader in the space sector.

The most challenging leg of Solar Impulse 2's landmark flight around the world powered only by the sun was delayed on Tuesday due to concerns about the weather, organizers said.

The single-seater aircraft was due to leave Nanjing, in eastern China, for the 8,500 kilometer (5,270 mile) flight over the Pacific Ocean to the U.S. island of Hawaii in the early hours of the morning. 

A rare pure white sparrow has been spotted in Australia, leaving ornithologists all aflutter Monday.

The albino was photographed at Sanctuary Lakes near Melbourne, but it is not expected to survive long with its snowy white plumage making it stand out to birds of prey.

Japanese Prime Minister Shinzo Abe on Saturday pledged $453 million in aid to Pacific island nations to help them combat climate change and natural disasters.

Abe made the pledge as leaders of 14 Pacific island nations gathered for a two-day meeting, which began on Friday in Iwaki, Fukushima prefecture, to discuss their development needs.

Was it a UFO? A sign that the end is nigh?

A rainbow-like halo surrounded the sun over Mexico City on Thursday, an optical phenomenon that triggered a social media frenzy of pictures and jokes about the end of the world.

A SpaceX Dragon capsule is back on Earth with a full load of cargo, after a quick trip home from the International Space Station.

The capsule, containing more than 3,000 pounds (1,360 kilograms) of experiments and equipment, splashed into the Pacific just off the Southern California coast Thursday less than six hours following its station departure.

A world of diversity has been discovered in plankton, the tiny plants, viruses and embryonic fish that are a favorite food of whales and supply much of the planet's oxygen, researchers said Thursday.

Plankton are important because they serve as the base of the marine food chain and provide half the oxygen generated on Earth by photosynthesis.

A popular webcam showing large male Pacific walruses lying on the beach with a Hitchcockian number of seabirds flying overhead is once again streaming to the Internet.

The high-definition stream from Alaska's remote Round Island had been dormant for nearly a decade after private funding ran out, but a version is back now, thanks to a philanthropic organization that operates a series of nature webcams from around the planet. The walrus cam, part of the Pearls of the Planet series, can be viewed at: http://explore.org/live-cams/player/walrus-cam-round-island.

Anthropologists said Wednesday that stone tools found in northwest Kenya dating back 3.3 million years challenge the mainstream story of mankind. 

The tools are an astonishing 700,000 years older than the first known implements, which have been attributed to Homo habilis, a forerunner of modern humans.