Penguin
From Tardis Wiki, the free Doctor Who reference
Penguins are birds that live in cold or hot places. Frobisher took on the form of a Penguin as his wife Francine had been fond of them. He occasionaly changed between variations of the species. (DWM: The Shape Shifter/Voyager) They mostly gather in polar regions. (DWM: Voyager)
Penguins were among the animals kept in a British zoo on which Cedric Matthews tested his aggression-enhancing formula. (TVC: The Arkwood Experiments)
In an alternate timeline, penguins lived on the River Nile in Egypt. (DW: The Big Bang)