These films are generally good at being good enough, and the fourth installment, Ice Age: Continental Drift, doesn't deviate from that modest tradition.

Logic may be extinct, but, boy, do these movies whiz by like ice cubes zipping across a linoleum floor.

The dialogue is sometimes too sluggish and definitely too preachy, the ending is a little too sappy, yet somehow this strange collection of prehistoric critters and their completely illogical life are consistently likable, if not quite lovable.

They keep pumping out more "Ice Age" movies, as if it were some sort of "Rocky" for kids or something, and if they never reach the heights of the best animated fare, they chug along efficiently.

"Continental Drift," like its predecessors, is much too friendly to dislike, and its vision of interspecies multiculturalism is generous and appealing.

A mild bounce back from the dinosaur doldrums of the last Ice Age movie.