Gertie the Dinosaur (Winsor McCay)

Gertie is a short animated film produced 1914 by an animator and cartoonist Winsor McCay it is the earliest animated film to ever feature a dinosaur. The inspiration for the story of this dinosaur in a comic strip called "Dream of the Rarebit Fiend"

Long-necked dinosaurs often appeared in Dream of the Rarebit Fiend. (May 25, 1913)

Winsor McCay from 1867 to 1934 had worked as a commercial artist and cartoonist by the time he started making newspaper comic strips such as Dream of the Rarebit Fiend

"McCay had earlier introduced dinosaurs into his comic strip work, such as a March 4, 1905, episode of Dream of the Rarebit Fiend in which a Brontosaurus skeleton took part in a horse race, and a May 25, 1913, Rarebit Fiend episode in which a hunter unsuccessfully targets a dinosaur; the layout of the background to the latter bore a strong resemblance to what later appeared in Gertie. In the September 21, 1913,episode of McCay's Little Nemo strip In the Land of Wonderful Dreams, titled "In the Land of the Antediluvians", Nemo meets a blue dinosaur named Bessie which has the same design as that of Gertie." 

Gertie was designed to look like it was answering every question that was asked of it e.g. "When her master McCay calls her, the frisky, childlike Gertie appears from a cave. Her whip-wielding master has her do tricks such as raising her foot or bowing on command. When she feels she has been pushed too far, she nips back at her master. She cries when he scolds her, and he placates her with a pumpkin." 

(http://en.wikipedia.org/wiki/Gertie_the_Dinosaur)

Preparing the thousands of drawings for the film, from the film's introduction