David Attenborough was an English broadcaster known for his nature programmes.
Ace compared a visit to the Great Rift Valley to being an extra in a David Attenborough programme. (PROSE: Prelude Birthright)
On Janus Prime, when the Eighth Doctor pointed out how easily a Janusian moved about the ruins, Sam Jones asked him to leave the David Attenborough bit till later. (PROSE: The Janus Conjunction)
After a narrow escape from a tyrannosaurus rex, the Tenth Doctor apologised to Martha Jones and suggested they'd stick to watching David Attenborough in the future. (PROSE: Made of Steel)
On Basingstoke, Amy Pond told the Eleventh Doctor that it felt weird standing in a jungle without a David Attenborough voice-over. (COMIC: Supernature)