Scarce water supplies in the western US will probably dwindle further as a result of climate change, a US government report says.

Ukraine marks the 25th anniversary of the world's worst nuclear accident - at Chernobyl - amid renewed global nuclear concern.

Male fallow deer interrupt fights between rivals to assert their dominance, according to scientists.

Intelligence tests are as much a measure of motivation as they are of mental ability, says research from the US.

Officials in Iran say they have found a new computer virus designed to target the country's government institutions.

Forecasters say there is currently just a 20% chance of poor weather conditions keeping shuttle Endeavour from launching on its final mission on Friday.

Speculation about a dramatic finding in the search for the elusive Higgs boson particle is premature, according to experts.