Visitor Sighting: An alien can be seen near the beginning of the episode, in Mr. Garrison's classroom, on the bulletin board behind the children. It is a picture or drawing of an alien amongst other pictures, and can be seen a couple of different times.
The scene where Pip asks the boys what's for lunch and the boys have a go at him was from the unaired plot from "Cartman Gets an Anal Probe". The explanation for this is that the scene was originally part of the pilot, but was cut for time and then inserted into this episode. The animation is significantly different than the rest of the episode, far cruder, as reflected by the style of the original pilot.
During the genetic experiment results K.C. is shown in his seat before he heads back to it with his weed and the first prize button is on Fluffy's cage for a second BEFORE Mr. Garrison awarded it. Mr. Hat awards the prize but Garrison's right hand is visible.
Dr. Mephisto is a Buddhist.
Two boys who made fun of Stan's dog in "Big Gay Al's Big Gay Boat Ride" appear in this episode but the shorter one's voice deepens here.
The windows of Stan's house change during episode. They are wide when Stan is thrown out by Shelly and when Mutant Stan comes.
In the cafeteria there is a chalkboard and it says:
HOT LUNCH MENU
1. Gumbo With Rice
The second dish is also known as "Shit on a Shingle".
The sign above the gate of the South Park Genetic engineering ranch has two bunny fish facing out and down at each end. Inside of the ranch the handle of Dr. Mephisto's cane is an ass.
This episode contains one of the first mentions of Cartman's mom's promiscuity. It also sheds a little light on Cartman's behavior possibly stemming from sexual abuse by Cartman's mom (see above quote about Cartman being forced to dress like a mailman).
Half of a scene that takes place in the lunchroom appears in the same frame-by-frame cardboard cut-out style that the pilot episode was entirely shot in. The style is notably different than the rest of the episode, including a noticeable difference in voices, mouth movement, scene coloring, and character positioning. The reason for this is that the scene was originally part of the pilot, but was cut for time and then inserted into this episode.
In the lunch room there is a sign with a visitor that says "Have you seen me?".
On the special-ed bus there is a blind kid, a kid with a big head, upside-down kid, the bus driver has a doctor's mask.
Stan's sister Shelly beats Stan up and you can see him laying on the floor in a puddle of water. Shelly originally threw lit matches on Stan and put him out with some water. However, the scene was removed before the episode aired and no one thought to remove the puddle that was on the floor.
When a cooked Kenny comes out of the microwave, his arms appear to be attached to his head. His body is also quite thin.
Mr. Hat: Genetic engineering lets us correct God's horrible, horrible mistakes - like German people.
Kyle: Oh my god! They killed Kenny! (to microwave) You bastard!
Bebe: I'd want a pot-bellied elephant.
Pip: Yes! I'd pay $50 for one!
Chef: Hey, I know you. You're that crazy cracker from up on the hill top.
Dr. Mephisto: Sir, if splicing the DNA of humans and various animals together is crazy…
Chef: Okay, but ya gotta get them in the mood.
Chef: Do what I do. Get them good and drunk.
What Kenny says in this episode:
1) When talking about pig and elephants, Kenny says "Hey you guys, I talked to Garrison and he told me they're like the same."
2) When talking about how much of a wuss Stan is for getting his ass kicked by a girl, Kenny say "Or are you gonna feather your hair?"
3) After Kyle says this about what Stan should do about his sister "Stan, you can use family love as a weapon against Shelley. The next time she's gonna kick your ass, just tell her, "Shelley, you're my sister, and I love you." Kenny says "And I want to take off your bra."
4) When the genetic doctor comes and tells the boys of Stan's clone, Kenny says "A big mutant Stan?!"
5) When Kenny sees the destruction that Stan's clone is causing, he says "Oh my God! What is he doing?!"
Mr. Garrison: Well spank my ass and call me "Charlie", it looks like we have two A students in a cloning war.
(Watching an elephant have sex with a pig)
Chef: Now I know how all those white women must have felt.
Stan: What about our elephant pig?
Dr. Mephisto: I'm afraid I can't do that. Have you heard that song by Loverboy? (breaks into song) Pig and elephant DNA just won't splice.
Stan: Officer, there's a clone that looks just like me that's wrecking the town.
Officer Barbrady: You boys have been watching too much of the X-Files. As you see here... (Stan's clone flings him into the lake) ...there is nothing to see.
Mr. Garrison: Hey Stan, are you wearing a new hat? (the Stan clone grabs him) I know someone with an itchin' for detention.
Dr. Mephisto: And here I spliced mongoose with ducks, mosquitoes with gorillas, and fish with little bunny ears.
Cartman: These ears are tied on with little strings!
Cartman: Why don't you go back to San Fransisco with the rest of the Jews?
Kyle: There aren't any Jews in San Fransisco, retard!
Stan: What is that?
Kyle: That's my new pet elephant. He was supposed to come in from Africa in 46 weeks, but it only took 3 weeks.
Stan: That's cool!
Kyle: No it's not! My mom doesn't let him in because his poop is bigger than the couch.
Cartman: My mom got me a pot-bellied pig, because its poop is small.
Ms. Crabtree: (about the elephant) Excuse me, but what is that?
Kyle: That's the new retarded kid.
Ms. Crabtree: Sorry, little girl, but you still can't get on. You'll have to take the special ed bus.
Cartman: If some girl tried to kick my ass I'd be like: Hey, Why don't you stop dressing me up like a mailman and making me dance for you while you smoke crack in the bedroom and have sex with some guy I don't even know on my dad's bed!
Kyle: Dude, what the hell are you talking about?
Cartman: I'm just saying Stan's a wuss is all.
Cartman: (about Pip) French people piss me off!
Cartman: Knit me a sweater before I smack you in the face.
Shelly: Who said that?
(Stan, Kyle, and Cartman point to Kenny.)
Mr. Hat: I'm your friend, Mr. Hat, Stan. You can tell me anything. Now, who hits you? Is it your father or your mother?
Stan: Well, neither one. It's my sister.
Mr. Garrison: Your sister? For God's sake, quit being such a little wuss! Stop wasting Mr. Hat's time with pansy, little fu-fu problems. And give me back my cocoa!
Dr. Mephisto: Have you you kids seen anything unusual lately?
Kyle: We just saw an elephant have sex with a pig.
Dr. Mephisto: No, I said unusual.
Kyle: The next time Shelly is going to hit you tell her: "Shelly, you're my sister and I love you."
Kenny: And I want to take off your bra.
Stan: Sick dude! She's my sister.
Kyle: Try it!
Dr. Mephisto: With genetic engineering we can correct all of God's horrible mistakes, like German people.
Chef: (singing) Pig and elephant DNA just won't splice.
When originally aired in Canada on Global, Mr. Garrison's line about genetic engineering being able to correct God's horrible mistakes, "like German people" was cut to remove the "like German people" part. However, this is uncut when aired on The Comedy Network.
The geologist from the episode "Volcano" turns out to be Stan's father Randy Marsh as revealed in this episode.
Dr. Mephisto makes his first appearance in this episode.
Shelly is based on Trey Parker's real sister, Shelly, who is three years older. When they were kids she used to beat Trey up, lock him out of the house, and once even threw him down a flight of stairs.
In the middle of the episode Shelley throws Stan around again. She throws him across the room and he lands on dry carpet. She walks over to him, and he's in a puddle of water. No explanation is offered as to how the puddle got there, but after some research, there is an explanation after all: There was a segment in there after Shelley walks over to Stan where she lights a match and throws it at him to light him up. Then she douses him with water a few times in regret and a puddle forms underneath him. When Comedy Central got the episode to air they asked Trey and Matt to take this piece out, because there have been real-life cases of children actually trying to set other kids on fire with lit matches. Mike Judge got in trouble over portraying this on Beavis and Butt-head, and CC didn't want that kind of trouble. Apparently, though, other nations DO get the original version, with Shelley setting Stan on fire and all.
The scene in the lunchline where the kids meet Pip is taken from the deleted scene in "Cartman Gets An Anal Probe".
The original title to this was "An Elephant F--ks A Pig", but the censors didn't like it. This was mentioned during the "Fireside Chat" segment that introduced the episode on the Season 1 DVD set.
Elton John Intro:
When Chef says "Ladies and gentlemen, Mr. Elton John!" is very similar to George Michael's introduction of Elton John in "Don't Let the Sun Go Down on Me!"
The Omen: Terrence: Daddy, nooo! When Terrence yells to his father Mephisto, as he shoots the Mutant Stan it is very similar to the 1976 film The Omen, when Gregory Peck is in the church and wants to stab his devil possessed son Damien.
That'll do pig. At the end of the episode, Cartman says this line from the 1995 film Babe, a story about a pig that acted like a dog.
The Island of Dr. Moreau: Mephisto was modeled after the Genetic Scientist Dr. Moreau from The Island of Dr. Moreau (1977). He was played by Marlon Brando in the 1996 remake, which is why Mephisto is a member of the National Association of Marlon Brando Look-Alikes (NAMBLA).
Dr. Mephisto's last name comes from Faust (or Faustus), the name of the protagonist in a popular German legend. He makes a pact with Satan, who's named Mephisto (or Mephistopheles). The legend was later made in to a play by Johann Wolfgang von Goethe during the 1800's.
Pip: Well, my father's name being Pirrip, and my given name being Philip, my infant tongue...
Anyone who has read Charles Dicken's "Great Expectations" should recognize this as Pip's first description in chapter 1.