Took a crew of 237 more than three years to finish the film.
David Morehead, an animator of this film, created reference footage by putting a camera on the back of his friend's dog and letting it run around his house. This gave the layout artists some great ideas about scale, animals' perspective, and how animals moved. In addition, the layout team compared a house to an apartment building and a kitchen to a cathedral.
The art department went to a bowling alley to sketch the design of the 'perfect' vending machine. They went to various supermarkets to sketch chip bags and bottles. They eventually got kicked out of a Safeway because the manager felt uncomfortable with them being there for such an extended amount of time.
The "forest side" of the hedge is based on the hedge in front of DreamWorks Animation. The exterior of the hedge is based on the vines growing in their parking garage. The hedge is approximately seven feet tall.
According to the film makers on the DVD commentary, the movie originally opened with R.J. sneaking into Vincent the bear's cave to steal his food. But, then they quickly realized that they were beginning with something very suspenseful and that R.J. would need a reason to go after the food in Vincent's cave, so they invented the "vending machine" sequence at almost the last minute.