The scientists said they had seen gorillas use tools to navigate swampy ground.

One gorilla reportedly used a stick to test the depth of a puddle in her path.

Another is said to have been seen using a tree trunk as a support while digging for herbs, and as a bridge to cross swampy ground.

"This is a truly astounding discovery," team leader Thomas Breuer said in a statement quoted by the Associated Press news agency.

Dr Nabarro stressed he would be working hard to control bird flu through contact with farming communities and markets where birds are sold and looking at the migration of wild birds.

He said the number of deaths from any future influenza pandemic would depend on where it started, how quickly it was discovered and the kind of response they got from governments.

"The range of deaths could be anything between 5m and 150m," said Dr Nabarro.

"I believe that the work we're doing over the next few months will make the difference between, for example, whether the next pandemic leads us in the direction of 150 or in the direction of five. "So our effectiveness will be directly measured in lives saved and the consequences for the world."

If 2005 goes down as the worst hurricane season on record in the North Atlantic, it will join 2004 as one of the most violent ever. And these two seasons are part of a trend of increasingly powerful and deadly hurricanes that has been playing out for more than 10 years. Says climatologist Judy Curry, chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology: "The so-called once-in-a-lifetime storm isn't even once in a season anymore."

Head-snapping changes in the weather like this inevitably raise the question, Is global warming to blame? For years, environmentalists have warned that one of the first and most reliable signs of a climatological crash would be an upsurge in the most violent hurricanes, the kind that thrive in a suddenly warmer world. Scientists are quick to point out that changes in the weather and climate change are two different things. But now, after watching two Gulf Coast hurricanes reach Category 5 in the space of four weeks, even skeptical scientists are starting to wonder whether something serious might be going on.

"There is no doubt that climate is changing and humans are partly responsible," says Kevin Trenberth, head of the climate-analysis section at the National Center for Atmospheric Research (NCAR) in Boulder, Colo. "The odds have changed in favor of more intense storms and heavier rainfalls." Says NCAR meteorologist Greg Holland: "These are not small changes. We're talking about a very large change."

While the headline-getting weather news story has been Hurricane Rita, temperatures have been ridiculously high for this time of year across a good chunk of the country. I mean, c'mon ... highs in the 90s all over the place and even 100+ degrees in many locations, within a week or two of October?!

There was a time at which reading anything more into that would have been the last thing you'd ever hear from me. I was a certified Global Warming Skeptic. As most climate scientists came to conclude that humans were changing the climate and those changes were significant, I, priding myself on also being an Objective Meteorologist, vehemently resisted as a result of what I felt was insufficient evidence.

I eventually came to the judgment that I was wrong and global warming was real, largely caused by human activities, and profoundly changing the planet on which we live. Even so, I was particularly opposed to the notion of "blaming" global warming for any single weather event. To this day I think that a lot of discretion needs to be used in making such connections.

The Arctic climate varies naturally, but the researchers conclude that human-induced global warming is at least partially responsible.

They warn the shrinkage could lead to even faster melting in coming years.

"September 2005 will set a new record minimum in the amount of Arctic sea ice cover," said Mark Serreze, of the National Snow and Ice Data Center (NSIDC), Boulder, Colorado.

"It's the least sea ice we've seen in the satellite record, and continues a pattern of extreme low extents of sea ice which we've now seen for the last four years," he told BBC News.

In the event that more than 21 named tropical cyclones occur in the Atlantic basin in a season, additional storms will take names from the Greek alphabet: Alpha, Beta, Gamma, Delta, and so on.

Max Mayfield told a congressional panel that he believes the Atlantic Ocean is in a cycle of increased hurricane activity that parallels an increase that started in the 1940s and ended in the 1960s.

The ensuing lull lasted until 1995, then "it's like somebody threw a switch," Mayfield said. The number and power of hurricanes increased dramatically.

Mayfield also listed a number of cities and regions in addition to New Orleans he believes are "especially vulnerable" to damage from a major hurricane: Houston and Galveston, Texas; Tampa; southern Florida and the Florida Keys; New York City and Long Island; and New England.

"Katrina will not be the last major hurricane to hit a vulnerable area," he said.

"The number of tornadoes associated with tropical storms and hurricanes was extraordinary and can be partially blamed for the high number of overall tornado reports," McCarthy said. Tropical Storm Bonnie and five land-falling hurricanes?Charley, Frances, Gaston, Ivan and Jeanne?affected the mid-Atlantic and Southeast states during August and September. Tornadoes frequently occur in the northeast quadrant of northward advancing tropical systems or their remnants.

Hurricane Frances produced the most tornadoes for a tropical system with a preliminarily number of 117 reports. Frances tops Hurricane Beulah, which spawned 115 tornadoes in September 1967. Hurricane Ivan was close with 104 tornado reports, and a total of 16 tornadoes were reported in association with Hurricane Jeanne.

NASA's Tropical Rainfall Measuring Mission (TRMM) satellite reveals a remarkable feature in this 3-D cat scan of Hurricane Rita - a pair of gigantic chimney clouds reaching more than 11 miles high. That is equivalent to 60,000 feet, or twice as high as a commercial airplane's cruising altitude. TRMM observed these hot towers in Hurricane Rita on September 19, 2005 during a period of brief intensification.

DATA FROM RECONNAISSANCE AIRCRAFT INDICATE THAT RITA HAS REACHED CATEGORY FIVE INTENSITY WITH ESTIMATED MAXIMUM SUSTAINED SURFACE WINDS OF 165 MPH. THIS WILL BE REFLECTED IN THE 4 PM CDT ADVISORY.

The entire stretch of coast from 500 miles south of Brownsville, Texas to Mobile, Alabama is at risk -- no one can say with any confidence where Rita will hit this far in advance. Texas and Louisiana are at the highest risk. The current model trend is to recurve Rita earlier and earlier, so residents from Corpus Christi to New Orleans need to be particulary concerned.

NASA's plan envisions being able to land four-person human crews anywhere on the Moon's surface and to eventually use the system to transport crew members to and from a lunar outpost that it would consider building on the lunar south pole, according to the charts, because of the regions elevated quantities of hydrogen and possibly water ice.

One of NASA's reasons for going back to the Moon is to demonstrate that astronauts can essentially "live off the land" by using lunar resources to produce potable water, fuel and other valuable commodities.

Such capabilities are considered extremely important to human expeditions to Mars which, because of the distances involved, would be much longer missions entailing a minimum of 500 days spent on the planet's surface.

NASA's Crew Exploration Vehicle is expected to cost $5.5 billion to develop, according to government and industry sources, and the Crew Launch Vehicle another $4.5 billion. The heavy-lift launcher, which would be capable of lofting 125 metric tons of payload, is expected to cost more than $5 billion but less than $10 billion to develop, according to these sources.

NASA's plan also calls for using the Crew Exploration Vehicle, equipped with as many as six seats, to transport astronauts to and from the international space station. An unmanned version of the Crew Exploration Vehicle could be used to deliver a limited amount of cargo to the space station.

Most predatory dinosaurs such as tyrannosaurs and velociraptors have usually been depicted in museums, films and books as covered in a thick hide of dull brown or green skin. The impression was of a killer stripped of adornment in the name of hunting efficiency.

This week, however, a leading expert on dinosaur evolution will tell the British Association, the principal conference of British scientists, that this image is wrong.

Gareth Dyke, a palaeontologist of University College Dublin, will tell the BA Festival of Science being held in the city that most such creatures were coated with delicate feathery plumage that could even have been multi-coloured. Fossil evidence that such dinosaurs were feathered is now "irrefutable".

"The way these creatures are depicted can no longer be considered scientifically accurate," he said. "All the evidence is that they looked more like birds than reptiles. Tyrannosaurs might have resembled giant chicks."

Katrina's sustained winds reached 175 mph and its minimum central pressure dropped as low as 902 millibars the fourth lowest on record for an Atlantic hurricane, NOAA's National Climatic Data Center reported.

The storm weakened slightly before it reached landfall and had less powerful winds than Hurricane Camille, which devastated coastal Mississippi in August, 1969.

But the size of Katrina, with hurricane force winds extending 120 miles from its center, was much larger and the destruction more widespread than Camille.

The central pressure in a hurricane is a good indicator of the strength of the winds of the storm. The strongest observed hurricane in the Atlantic basin was Gilbert in 1988 with a pressure of 888 millibars in the northwest Caribbean. Normal average sea level air pressure is 1,016 millibars.

THIS TROUGH WILL NOT BE DEEP ENOUGH TO SIGNIFICANTLY ACCELERATE THE CYCLONE... HOWEVER...AND THIS IS LIKELY TO RESULT IN AN EXCRUCIATINGLY LONG PASSAGE OF THE HURRICANE ALONG THE NORTH CAROLINA COAST OVER THE NEXT COUPLE OF DAYS. THE SLOW MOTION...COUPLED WITH THE RATHER LARGE RADIUS OF MAXIMUM WIND...IS EXPECTED TO RESULT IN EXTENDED PERIODS OF HEAVY RAINFALL...WITH WINDS AT OR NEAR HURRICANE FORCE...OVER MUCH OF THE WARNING AREA.

The bug - which has the scientific name cymothoa exigua - was discovered inside the mouth of a red snapper bought from a London fishmonger.

The 3.5cm creature had grabbed onto the fish's tongue and slowly ate away at it until only a stub was left.

It then latched onto the stub and became the fish's "replacement tongue".

They say it probably began growing in 1997 and has been rising ever since at a rate of about 1.4 inches a year. It was first observed from space using a relatively new imaging technology known as radar interferometry that can measure changes in the Earth's surface.

The likely cause of the bulge is a pool of magma that, according to Deschutes National Forest geologist Larry Chitwood, is equal in size to a lake 1 mile across and 65 feet deep.

The magma lake is rising 10 feet each year, under tremendous pressure, and it deforms the Earth's surface as it expands, causing the bulge.

Other causes could be anything from the birth of a new volcano - a fourth Sister in the making - to a routine and anticlimactic pooling of liquid rock, researchers say.