Ice Age: Dawn of the Dinosaurs opens with the stitched-together prehistoric family about to become a biological one: Manny and his mate Ellie are expecting a baby mammoth. Unfortunately, this makes Sid the sloth and Diego the saber-toothed tiger feel left out. Diego, who worries he’s losing his edge, decides to head out on his own, while Sid adopts three suspiciously large eggs that he’s found through a crack in the ice. The eggs turn out to be dinosaur eggs from a pre-mammalian underworld, and when the mama T-Rex comes to rescue her rambunctious little ones, Ice Age: Dawn of the Dinosaurs transforms into a delightful comic adventure. Clearly, the animators have been inspired by a wild fusion of Road Runner cartoons and Buster Keaton. They have great fun with the differences in scale between the mammals and the dinosaurs, and the introduction of a deranged Australian weasel named Buck pushes everything into Loony-Tune territory. Let Pixar tug at our heartstrings; Ice Age aims to tickle the funny bone and does a fine job of it. --Bret Fetzer