Seals were Earth marine mammals. In the 1900s, Vince Hawkins, a lighthouse keeper on Fang Rock, told Leela that he talked to seals to combat boredom. (TV: Horror of Fang Rock)
Seals were among the animals kept in the sea room of Shaun Brett's monument to his deceased father in Alaska. When the Permians revived in 1994, they inadvertently used their bioelectric fields to fuse the seals' bodies with those of the other animals to form monstrous hybrids. (AUDIO: The Land of the Dead)
Seals were among the marine animals accidentally killed by the Arill during their visit to Earth in the 12th century. Their bodies washed up on the shore near Lowith, where they were gathered by the villagers for food (seal fat was rendered and used to make candles). (PROSE: Dark Horizons)