**1/2 (86m | PG)
A largely forgettable, computer-animated screwball adventure about four animals who escape from the Central Park Zoo and eventually end up lost on a tropical island, “Madagascar” has good energy, fairly steady chuckles for kids (fart jokes and spit-takes galore), and a few out-loud laughs for adults (mostly stemming from hilarious homages to movies from “Chariots of Fire” to “American Beauty” to “Planet of the Apes”). But eliciting more than a passing interest in the creature characters and their escapades is another matter. While the animation is creatively stylized (blocky toes, spiraled nostrils and amusing flexibility), their personalities have no panache because the voices of Ben Stiller (egotistic lion), David Schwimmer (hypochondriac giraffe) and Jada Pinkett-Smith (sassy hippo) lack verve. Chris Rock’s impish zebra, whose itch to explore is the catalyst for their adventure, has some personality, but even he’s upstaged by an incidental passel of prison-thug penguins who are also zoo escapees. While amusing enough for a cheap Saturday matinee, “Madagascar” doesn’t have the Pixar-like originality, panache, heart and ageless humor required to stand the test of time.