The ex-chief scientist says the government should be made to enshrine a zero-emissions target in law.

Diprotodon, an extinct Ice Age marsupial of Australia, would trek long distances each year for food.

Ripples in the fabric of space-time are sensed again - this time using three different laser systems.

The BBC is going under the waves with David Attenborough in a second series of Blue Planet, which was first shown in 2001.