Sir David Attenborough's 100th birthday will be celebrated with three special programmes, the BBC has announced. The corporation will mark Sir David's "extraordinary milestone" on 8 May with a week of special programming featuring new and old shows by the beloved presenter. One of the new programmes, titled Making Life on Earth: Attenborough's Greatest Adventure, will go behind the scenes of his landmark BBC One series. Life on Earth was first broadcast in 1979 and followed Sir David as he