Birds sense posted speed limits on roads and react to avoid collisions, according to a study out Wednesday.

Researchers said birds appear to have adapted to the local speed limits as a feature of their environment, such as the risk of predators.

Since the first test-tube baby was born more than three decades ago, in vitro fertilization has evolved into a highly sophisticated lab procedure. Now, scientists are going back to basics and testing a simpler and cheaper method intended mainly for developing countries.

In the West, many would-be parents spend thousands of dollars for IVF, which involves pricey incubators and extensive screening. But European and American scientists say a simplified version of the entire procedure aimed at developing countries could be done for about 200 euros ($265) with generic fertility drugs and basic lab equipment that would fit inside a shoebox.

Scientists studying the H7N9 bird flu virus that has killed more than 40 people since March said Wednesday they had discovered another H7-type virus lurking in chickens in China.

Dubbed H7N7, the virus was able to infect mammals in a lab experiment, said the team, warning H7 viruses "may pose threats beyond the current outbreak".

Colombia on Wednesday more than doubled the size of a huge nature reserve as it fights to protect the Amazon from deforestation.

Environment Minister Juan Gabriel Uribe said deforestation of the Colombian Amazon is a worrisome problem, mainly because of land being cleared for growing coca leaves, logging, illegal mining and agriculture.

The larva of a Vietnamese moth has devised a unique form of transport -- constructing a leaf cone and thrashing about inside to make it jump, a study showed Wednesday.

Even more remarkably, the tiny caterpillar manages to steer its leafy vehicle in a clear direction along the forest floor -- but always away from the Sun, Canadian scientists wrote in the journal Biology Letters, published by Britain's Royal Society.

Human activity is almost certainly the cause of climate change and global sea levels could rise by several feet by the end of the century, according to an Intergovernmental Panel on Climate Change (IPCC) report leaked to media on Tuesday.

The draft summary of the report all but dismissed recent claims of a slowdown in the pace of warming, which has seized upon by climate-change sceptics.

Deforestation in the Brazilian Amazon is on the rise sharply, sparking alarm over the future of the world's biggest rainforest.

Between June and last August, Imazon, the first independent monitoring system for the area, detected a 100 percent surge in the clearing of land.

Jubilant conservationists expressed hope Tuesday for the survival of the critically-endangered giant ibis after a nest of the bird species was discovered in a previously unknown habitat in northeastern Cambodia.

Habitat loss and poaching has pushed the giant ibis to the edge of extinction, with around only 345 of the reclusive creatures -- distinctive for their bald heads and long beaks -- left anywhere in the world, 90 percent of them in Cambodia.

The earliest iron artefacts ever found -- funeral beads strung around bodies in a 5,000-year-old Egyptian cemetery -- were made from a meteorite, archaeologists said on Monday.

Hi-tech scanning of the beads, discovered by British archaeologists in the Lower Egypt village of el-Gerzeh in 1911, shows the metal came from a rock in outer space, they said.

China, the United States and Qatar were accused of environmental plunder on Tuesday as green activists marked "Earth Overshoot Day," the date at which mankind has exhausted a year's budget of natural resources.

"In just over eight months, we have used as much nature as our planet can regenerate this year," Global Footprint Network, an international thinktank which calculates the metric, said in a press release.