The marble features of some of Rome's most famous statues were obscured by gas masks yesterday as part of a protest against traffic pollution organised by an environmental pressure group.

Under the slogan "The statues say NO to pollution from CO₂ emissions!," the group Terra! are lobbying for the EU to reduce the ceiling for cars' carbon dioxide emissions. The masks and CO₂ placards appeared overnight on statues of saints, poets, angels and emperors in piazzas and on bridges throughout the capital, before being removed by the authorities.

Terra! ( www.e-terra.it ) says the EU has failed to make good on pledges to lower the CO₂ emissions limits of new cars and protests against the rising sales of high-emission Sports Utility Vehicles.

Wandering polar bear shot

Icelandic authorities said they were forced to shoot a polar bear found wandering on the island in order to protect the public after a plan to anaesthetise the animal was abandoned.

The bear, an adult male weighing around 250 kilogrammes, was presumed to have swum to shore from drifting ice. The last time a polar bear came ashore in Iceland was in 1988.

"There was a lot of fog in the area and the bear was moving into the fog. We couldn't risk losing him and there was no time to wait for anaesthetics, so we had to shoot him. It was for the safety of the public," Police Superintendent Stefan Vagn Stefansson told Icelandic national radio.

In response to a public outcry at the shooting, the environmental ministry said it would review the incident to see if it could avoid shooting the next bear that lands in the country.

People are creatures of habit

Researchers who tracked 100,000 people using their cell phone signals confirmed yesterday that most human beings are indeed creatures of habit.

Most of us go to work, to school and back home in surprisingly predictable patterns, something the researchers said would be useful in city planning and preparing for emergencies.

"Despite the diversity of their travel history, humans follow simple reproducible patterns," Albert-Laszlo Barabasi of Northeastern University in Boston and colleagues wrote in their report, published in the journal Nature. "This inherent similarity in travel patterns could impact all phenomena driven by human mobility, from epidemic prevention to emergency response, urban planning and agent-based modeling," they added.

They used data collected by a European mobile phone carrier for billing and operational purposes. "It contains the date, time and coordinates of the phone tower routing the communication for each phone call and text message sent or received by 6 million customers," they wrote.

Vote bans marijuana cultivation

Mendocino County's reputation as a marijuana haven of California may be going up in smoke. Voters have leaned towards repealing a law allowing home marijuana growing, according to preliminary results of a ballot measure vote released yesterday.

Critics say a cottage industry had grown out of control.

California in 1996 voted to allow possession and cultivation by residents of marijuana for medical purposes, despite federal law which declares it illegal.

Mendocino, a rural county north San Francisco, in 2000 approved marijuana cultivation for recreational use as well, voting to let residents grow up to 25 marijuana plants, compared with the state limit of six.

With about a third of the vote counted, 52 per cent supported repeal. The tally may not be complete for up to four weeks.

Judge unveils video game

America's first female Supreme Court justice has unveiled a video-game project to teach children how courts work, saying she wanted to counter partisan criticism that judges are "godless" activists.

Sandra Day O'Connor, 78, who served as US Supreme Court justice from 1981 until her retirement in 2006, said she never imagined she would be asked to address a conference about digital gaming. She said she got involved with developing the project called Our Courts out of concern over public ignorance about the judiciary and partisan attacks on what should be an independent institution.

Judge O'Connor said she had seen from her own grandchildren that technology was the best way to inspire children to learn and it was vital to speak to them in their own language.

Asked what videogames she has played herself, she said: "I don't play videogames. Sorry."

Canadians urged to scrap old cars

Canadians will be offered bicycles, public transit passes or cash if they agree to scrap their old gas-guzzling vehicles.

Ottawa says five million of the 18 million cars and trucks in Canada were made before 1996, when tougher emissions standards were introduced. The older vehicles produce about 19 times more pollutants than newer models.

The Conservative government, heavily criticised for effectively abandoning the Kyoto protocol on climate change, is keen to show it is doing something to curb emissions and protect the environment.

Whether the programme catches on outside major cities is another matter. Canada is the world's second largest country with a relatively underdeveloped public transit network.

The National Vehicle Scrappage Programme will be up and running by January 2009. Other incentives include C$300 (€192) in cash, membership in a car-sharing programme or a rebate on the purchase of a new vehicle.