"An Elephant Makes Love to a Pig" is the fifth episode of the first season of the American animated television series South Park. It first aired on Comedy Central in the United States on September 10, 1997. In the episode, the boys of South Park try to force Kyle's pet elephant to crossbreed with Cartman's pet pig for a class project on genetic engineering. Meanwhile, Stan tries to deal with his sister Shelley, who keeps beating him up. The episode was written by series creators Trey Parker and Matt Stone along with Dan Sterling. The episode served as both a parody of genetic engineering and a statement against its potential evils. The scenes of Stan getting beat up by his sister were inspired by Parker's real-life childhood experiences with his own sister, who is also named Shelley. "An Elephant Makes Love to a Pig" was met with generally positive reviews, and has been described as one of the most popular early South Park episodes. Several commentators praised its satirical elements with regard to genetic engineering. The episode marked the first appearance of Shelley Marsh, Stan's mother Sharon Marsh, and the mad scientist Dr. Mephesto, who was inspired by the title character of the 1996 film, The Island of Dr. Moreau. Plot The boys are waiting at the bus stop when Cartman notices Stan has a black eye and it turns out his sister Shelley has been beating him up, all because she got new headgear at the dentist. Kyle has problems of his own; his mom will not let him keep his new pet elephant in the house. At school, Mr. Hat teaches the class about genetic engineering, which prompts Kyle to decide to crossbreed his elephant with Cartman's pot-bellied pig, Fluffy, to make little "pot-bellied elephants", which he could keep in his house. Upon hearing this, Terrance Mephesto bets Kyle that he can clone a whole person before Kyle can create a pot-bellied elephant. Mr. Garrison suggests the boys use their genetic modifications for the upcoming science fair and go to the South Park Genetic Engineering Ranch. At the ranch, Dr. Mephesto shows them his genetically engineered collection, including several different animals with four pairs of buttocks, such as a monkey, ostrich and mongoose. Mephesto then explains that, just like the Loverboy song says, "pig and elephant DNA just won't splice", and steals a blood sample from Stan and