Bernie the gorilla and Kevin James' Griffin work as a buddy comedy duo.

The surprising accomplishment for Travers was "that the monkey's performance plus Adam Sandler as Donald plus our animator's performance made a new entity that took on a life of its own. To me that's the difference: the animals feel like characters."

Originally, Travers thought the bears would be the most difficult from a rigging standpoint with a very amorphous face, so they set up a more arbitrary rig that was driven by curves underneath the surface. The giraffe was similar, bending nose and lips in odd ways. "The monkey took the longest," according to Travers, "because its face is closest to human topology, and forced us to spend more time to get it right."

But the lions were the most difficult because the upper lip doesn't curl outwards to form readily apparent speech patterns. The answer was to carefully move into the necessary shapes that deviate from that animal's natural movement. "We entered this gray area where we had to make sure that it doesn't look cartoony."

Anything but for Zookeeper.

Bill Desowitz is former senior editor of AWN and editor of VFXWorld. He has a new blog, Immersed in Movies (www.billdesowitz.com), and is currently writing a book about the evolution of James Bond from Connery to Craig, scheduled for publication next year, which is the 50th anniversary of the franchise.