Pig
A pig was a four-legged animal native to Earth.
Certain religions, like Islam and Judaism, forbade the eating of pigs, a practise that continued and evolved even after pigs went extinct. (BNA: The Mary-Sue Extrusion)
Pigs were also used for a variety of experiments, likely due to their prevalence and biological features similar to humans. In 1930s , the Cult of Skaro turned the less intelligent people they captured into Pig slaves, humanoids with pig-like features, to work for them. (DW: Daleks in Manhattan/Evolution of the Daleks)
In 2006, a pig was augmented by the Slitheen family as a hoax alien invader. It was then planted in a ship to act as a diversion from the family. (DW: Aliens of London)
In the 51st century Mr. Sin, a cyborg with the brain of a pig, was created. (DW: The Talons of Weng-Chiang)
The Doctor once declared that a number of planets were home to a variety of pig that could fly. (GN: The Only Good Dalek)
Sock Pig was a toy made from a sock in the form of a pig. It was brought to life by the Anima. (ST: Sock Pig)
