I like Scrat. You like Scrat. We all, apparently, like Scrat.

But no one, I suspect, likes the saber-toothed cartoon squirrel — who, along with his beloved, ever-out-of-reach acorn, made only brief appearances in both of the first two “Ice Age” films — enough to want to watch a whole movie about him. Nevertheless, there he is, popping up seemingly every 10 minutes in “Ice Age: Dawn of the Dinosaurs,” the third and barely funny installment in the series of animated features about the prehistoric adventures of Manny (voice of Ray Romano), Diego (Denis Leary) and Sid (John Leguizamo), a woolly mammoth, saber-toothed tiger and ground sloth stuck in a snowbound world.
Scrat’s annoying ubiquity — compounded by the appearance of a new female love interest, Scratte (Karen Disher) — is just one piece of evidence that “Dawn of the Dinosaurs” has been focus-grouped and is now trying to please its presumed young audience a little more than is healthy. Others include jumping on the digital 3-D bandwagon and introducing not one, but three, adorable baby T. rexes.
Of course, there’s nothing wrong with cute. And there is a little vinegar to temper all that sugar. Simon Pegg makes a nice acerbic addition to the cast as Buck, a leathery, one-eyed weasel who carries a sharpened dino tooth for a dagger and who acts as a native guide when our heroes discover a lushly tropical world of still-living dinosaurs hidden under all that ice.
That’s right. Never mind the improbable physics and imaginative paleontology of that scenario (let alone the fact that the Ice Age seemed to be over in the last sequel, “Ice Age: The Meltdown”). Logic should never stand in the way of squeezing one more chapter out of a popular movie franchise.
What propels Manny and company underground is the pursuit of Sid, who’s been abducted by the mama T. rex after Sid attempts to raise her three offspring in a fit of misplaced parental instincts. It seems that even Sid wants babies, especially after Manny’s woolly-mammoth consort, Ellie (Queen Latifah, introduced in the last film), is discovered to be with child.
Complicating matters is the arrival of Rudy, the nasty beastie who took Buck’s eye and lost a tooth in the deal. Resembling a giant albino crocodile, he’s scary — my 9-year-old son insisted on holding my hand at one point — but he never really feels like anything more than a plot device.
That’s really, in a nutshell, the whole problem with “Ice Age: Dawn of the Dinosaurs.” It looks like a real movie, all right. And it’s got all the features people want: more Scrat, dino-babies, 3-D and the resurfacing of the themes of family and togetherness that were the hallmark of the first two films.
It’s not utterly without charm, either. Only here, that charm feels less earned than manufactured, a product not of evolution — or even intelligent design — but of cynical, soulless opportunism.