Characters exist only within the boundaries of a fictional world, while actors animate them from underneath, within, or behind. But animal characters are not always played by animal actors; in other words, an animal performance can be achieved without animals. Humans can animate animals, as did the "Half-boy," Johnny Eck (1911–1991), who played a bird creature and the "Gooney-bird" in Tarzan the Ape Man (1932), Tarzan Escapes (1936), and Tarzan's Secret Treasure (1941), and Joe Martin, who played a chimp or an ape in Making Monkey Business (1917), Monkey Stuff, Jazz Monkey (1919), Prohibition Monkey (1920), and Down in Jungle Town (1924). Other examples of human-generated animal performance include the apes in the "Dawn of Man" sequence in 2001: A Space Odyssey (1968), the woodland gorillas in Instinct (1999), and the apes who nurture John Clayton (Christopher Lambert) in Greystoke: The Legend of Tarzan, Lord of the Apes (1984).
A screen animal can be composed through graphic art (see the title sequence of The Pink Panther ), computer animation (the shocking dissected horse in The Cell , the invisible gorilla in Hollow Man , the spunky little rodent hero of Stuart Little [vocalized by Michael J. Fox, 1999], the giant cockroach in Men in Black ), or some form of animatronic mechanical artifice (the protagonist in King Kong [1933 and 1976], the shark in Jaws , affectionately called "Brucie" during production, the goofy kangaroo [animatronics by Jocelyn Thomas, vocalization by Adam Garcia] in Kangaroo Jack , the giant squid—live footage intercut with rubber puppet arms—in 20,000 Leagues under the Sea ).
Animal actors may play animal characters of a different breed or species. In Red River , for example, historical accuracy would have called for the herds to be played by longhorn cattle. But very few longhorns were available to Howard Hawks, and so he placed them close to the camera—a procedure requiring considerable production time. Most of the cattle were actually Herefords, who, in deep perspective (where details would not be visible to the audience) played longhorns. In Legend (1985), a horse portrays a unicorn.
Just as with human performance, so with animal participants, narrative action does not require that characters look realistic even when they are played by real animals. Thus, the long chain of cinematic animal monstrosities and monsters: played by made-up, costumed, and/or photographically enhanced actors, animal or otherwise, or animated through increasingly sophisticated and expensive techniques. The flying monkeys in The Wizard of Oz (1939), for example, are people dressed up as monkeys dressed up with wings, then hoisted through the air on invisible wires. The various alien animals in the Star Wars saga (1977 onward) are manufactured using latex prostheses and specially designed costumes or are computer animated. Puppetry and matte photography are used for the flying dog sequence of The Neverending Story (1984). In Mars Attacks! (1996), a Chihuahua is grafted onto a human brunette using digital animation.
What is essential in scenes played between humans and animals is the sense of copresence and mutual awareness. But an animal's "awareness" onscreen may be established narratively. Consider the attack of the giant spider in The Incredible Shrinking Man (1957). A man shrinks to the size of a pea and retreats to his basement, where he encounters a household spider. Photographed from his perspective, the spider is a giant. In order to achieve this effect, the director Jack Arnold simply matted together shots of the actor Grant Williams on a set made of enormous props with shots of a normal spider taken through a telephoto lens. The spider onscreen seems properly bellicose and unyielding, a true enemy of human flesh, yet the actor who plays this spider is a spider unaware of its own performance. The millions of ants that mount Charlton Heston in The Naked Jungle (1954) do not need to know they are acting in order to perform brilliantly.
Sometimes the entertainment value for the audience is provided precisely by the lack of clarity as to whether or not an onscreen animal is "in the know." A beautiful example is given in Lost in La Mancha (2002) by a horse who has been patiently trained by an off-camera handler to work with an actor in a scene of the film-within-afilm. Standing in for the actor, the handler coaches the horse to creep up from behind and nuzzle him forward along a path, a kind of "guiding spirit." The horse learns his routine brilliantly. But when the actor Johnny Depp shows up and the director calls for action, the now apparently starstruck horse refuses to move. A similarly "transcendent" consciousness, played for pathos, not laughs, characterizes the wailing puppy in Hitchcock's Secret Agent (1936). Far off, through a window, we see the dog's master being strangled on a mountaintop, while a mile away, near the camera, the dog is crying.
While the performances by human actors are sometimes obtained involuntarily, the screen performances of animals are, in some sense, always produced this way. Ultimately, what the animal does in front of the camera is behave rather than perform. It is through editing, shot selection, and narrative technique that the animal's behavior is transformed into a screen performance. When narrative techniques of constructing cinema are notably absent, the participating viewer's imaginary construction of animal behavior as screen performance is especially salient: if the milkman's dog, for instance, in The Dog and His Various Merits (Pathé Frères, 1908) gazes occasionally at the camera with no discernible tendency to play to it, the viewer can still construct him as a screen actor. Equally oblivious to the camera, yet deeply engaging, are the ostrich, mules, horses, camel, elephants, and goats who parade through the Lumières' Promenade of Ostriches, Paris Botanical Gardens (1896) and the swimming horses in Dragoons Crossing the Saône (1896).
Early cinema was full of animals who were either transformed into actors by the viewer's gaze or carefully trained to behave before the lens. Some animals "acted" in early cinema by performing their own deaths. In a famous early Edison film, Electrocution of an Elephant (1903), Topsy is put to death for the delectation of viewers (who are not informed by the film that earlier she had killed three humans, one for feeding her a cigarette). In Nanook of the North (Robert Flaherty, 1922), seals are routinely slaughtered by Inuit. Other early films featured explicit animal performers. Early Edison catalogs advertise Pie, Tramp and the Bull Dog (1901) ("Tramp enters, sees bull dog in kennel. Retreats, re-enters on stilts. Starts eating pie from a shelf. Bull dog jumps from window, throws tramp and shakes him up"), Laura Comstock's Bag Punching Dog (1901), and A Donkey Party (1903). An interesting early dramatist of animal life onscreen was Nell Shipman, notably in Back to God's Country (1919), where a wild dog named Wapi is rescued from beating by the filmmaker acting as protagonist.