He is the crazed drummer of Dr. Teeth and The Electric Mayhem. Animal was performed by Frank Oz from his first appearance in the pilot for The Muppet Show until his 1999 appearance in Muppets from Space, and has been performed regularly by Eric Jacobson since his 2002 appearance in It's a Very Merry Muppet Christmas Movie. On The Muppet Show, his drumming is performed by Ronnie Verrell. Animal has had roles in all of the Muppet movies, and was the only member of The Electric Mayhem to be included regularly on the Muppet Babies cartoons. He was voiced by Howie Mandel in the first two seasons of Muppet Babies, followed by Dave Coulier in subsequent seasons. Drew Massey operated Animal in Statler and Waldorf: From the Balcony. In Jim Henson's Little Muppet Monsters, Animal was voiced by Hal Rayle (who also voiced Miss Piggy and Gonzo).
Animal's vocabulary is generally limited to guttural shouts and monosyllabic grunts, often repeating a few simple phrases. During performances, Animal is usually chained to the drum set, as his musical outbursts are extremely violent. From The Muppet Movie:
Floyd Pepper: Oh, yeah, that's Animal. Show 'em what you do, Animal.
Animal: I what do: Eat drums!
[chews on a cymbal]
Dr Teeth: No, no, beat drums, beat drums!
Animal: Beat drums! Beat drums!
[beats the drums with his head]
Floyd Pepper: Down, Animal!
Floyd Pepper: Back!
Floyd Pepper: Sit!
[He sits quietly for a moment, panting, then snickers to the camera]
While it has been suggested that Animal's character was partially inspired by The Who drummer Keith Moon, there is no evidence in the original sketches for the character that suggest that he was based on anyone in particular. Animal is portrayed as an excellent drummer, playing with and/or against both Buddy Rich and Harry Belafonte in separate drum-offs on The Muppet Show. (The Rich sketch ended with Animal breaking a drum over Rich's head.) He shows a talent for jazz in a television advert for the Renault Clio car with French footballer Thierry Henry.
Animal has also run afoul of Muppet Show guests, such as the aforementioned scene with Buddy Rich. When he kept interrupting Rita Moreno's rendition of "Fever" with loud drumming outburts, she appeared to become so annoyed that she slammed his head between a pair of cymbals (to which Animal responded by saying "My kinda woman!", before passing out). Animal's attitude towards Dudley Moore became quite hostile when Moore tried to replace the band with a programmable, music-playing robot.
A regular gag involves someone imparting a figure of speech to Animal: Animal turns to the audience, his eyes go wide and then he goes berserk, taking it literally. For instance, Jim Nabors once spoke the traditional theatrical good luck wish, "Break a leg," whereupon Animal decided to indulge him by trying to break Nabors' leg. Another gag would occasionally occur when the band plays a slow song: Animal will get about halfway through and then after announcing "Too slow!" launch into a faster paced version of the song. The band would usually comment that Animal lasted much longer than they thought he would.
Animal has been depicted as a literal skirt-chaser (in The Muppets Take Manhattan, he chases a female co-ed out of the auditorium, chanting "Woo-maaaan!" after her). He also chases cars. Sometimes his wild and crazy appearance, attitude and antics are used as the source of a joke by way of a reversal of what the audience might expect from Animal, such as in this piece of dialog from The Great Muppet Caper, where it is revealed that Animal has a passion for impressionist paintings, especially those of Pierre-Auguste Renoir:
Kermit the Frog: What's wrong with your drummer? He looks a little crazed.