In theory, Jack Black and Michael Cera make the perfect odd couple. Black’s comedy emanates directly from his anarchic spirit and love of all things crass, which is accentuated by his devilish leer and cocked eyebrows, while Cera’s comedy comes from his deep well of insecurity and general confusion, which is captured so well in the blank stare you often see on posters bearing his visage. It’s a shame, then, that their pairing in this prehistoric comedy doesn’t yield more. There are certainly some funny moments, but too much of it feels like it should be funnier than it is. (Hollywood Jewel 16, Waco, TX)