Elephant

An elephant was a type of proboscidean related to the mammoth. It was found on the planet Earth.

Among the prizes the First Doctor won in a game of backgammon against Kublai Khan in the 13th century were thirty-five elephants with ceremonial bridles. (DW: Marco Polo)

Elephants were one of the animal species brought on board the Ark to escape the destruction of Earth. Dodo Chaplet pointed an Indian elephant out to the First Doctor and Steven Taylor and they proceeded to pet it. (DW: The Ark)

The Second Doctor and Jamie McCrimmon once used a herd of animals – which included s – to stampede a group of Quarks. (TVC: Jungle of Doom)

The Seventh Doctor and Ace saw elephants living in the Ngorogoro Crater in 1926. (DWM: Prelude: Birthright)

Cultural references to elephants
In Voyager's dream world, a waterfall existed that was bordered by two elephant statues. (DWM: Voyager)

Human folklore stated that elephants never forget anything. It was a running gag between the Sixth Doctor and his companion Melanie Bush that she had the memory of an elephant. (DW: The Ultimate Foe, BFA: The One Doctor, DW: Time and the Rani, BFA: Unregenerate!)