Fossil sheds light on hippos' relation to whales

An ancient relative of the hippopotamus likely swam from Asia to Africa some 35 million years ago, long before the arrival of the lion, rhino, zebra and giraffe.  Analysis of the previously unknown, long-extinct animal also confirms that cetaceans are the hippo's closest living cousins.

Gold rises in bubbles to Earth's surface

Valuable metals like gold, copper and platinum, reach the Earth's surface from deep underground by floating up on vapour bubbles.  The findings may also provide support for one hypothesis explaining the greatest mass extinction event in Earth's history.  Known as the great dying, the Permian-Triassic extinction event 252 million years ago killed off 70 per cent of terrestrial and 96 per cent of all marine life on Earth. Its cause remains a mystery.