The legend that is David Attenborough is honoured in this special tonight on the BBC to mark the naturalist and broadcaster's 89th birthday. The man himself will be discussing his television career as well as his recent record-breaking dive on the Great Barrier Reef. He will also be reflecting on some of the new issues affecting the natural world in recent years and asking none other than President Barack Obama what can be done to help ensure that the world this generation leaves behind for those that follow will be sustainable.