The Great Barrier Reef off the Queensland coast is home to a wealth of marine life

A UN team has arrived in Australia to investigate possible damage to the Great Barrier Reef by the mining industry.

South Africa troops tackle rhino poachers

Justice Minister Jeff Radebe said four military companies would be sent to the borders with Zimbabwe, Swaziland and Lesotho. Syndicates export the horns from Africa to parts of Asia and the Middle East. In 2011, a record 450 rhinos were killed by poachers in South Africa, the Department of Environment Affairs says. Mr Radebe said about 600 soldiers would join the fight against rhino poaching. "The deployment includes army engineers who are conducting repairs and maintenance on the Zimbabwe-Mozambique border fence, which is approximately 140 kilometres (85 miles)," Mr Radebe said. Last year troops were deployed along the Mozambican border, many of them inside the world-famous Kruger National Park where more than 200 rhinos were killed last year.

Canadian government is 'muzzling its scientists'

The Canadian government has been accused of "muzzling" its scientists.

Speakers at a major science meeting being held in Canada said communication of vital research on health and environment issues is being suppressed. But one Canadian government department approached by the BBC said it held the communication of science as a priority. Prof Thomas Pedersen, a senior scientist at the University of Victoria, said he believed there was a political motive in some cases. "The Prime Minister (Stephen Harper) is keen to keep control of the message, I think to ensure that the government won't be embarrassed by scientific finding by Canadian scientists that run counter to sound environmental stewardship," he said.

“I suspect the federal government would prefer that its scientists don't discuss research that points out just how serious the climate change challenge is." Professor Thomas Pedersen University of Victoria

Predators have roamed the planet for 500 million years. The earliest is thought to be some type of simple marine organism, a flatworm maybe or type of crustacean, perhaps a giant shrimp that feasted on ancient trilobites. Much later came the famous predatory dinosaurs such as T. rex, and later still large toothed mammals such as sabre toothed cats or modern wolves. But one or two hundred thousand years ago, the world’s most powerful predator arrived. Us. We lacked big teeth or sharp claws, huge tentacles or venomous bites. But we had intelligence, and the guile to produce tools and artificial weapons. And as we became ever better hunters we started harvesting animals on a great scale. We wiped out the passenger pigeon, the dodo, the great herds of North American bison. Last century we decimated great whale populations. Today the world’s fishing fleets routinely take more fish than scientists say is sustainable, leading to crashes in cod numbers for example, while people kill more large mammals in North America than all other causes put together. But out of our mass consumption of the world’s fauna appears a curious conundrum.