Chuck Jones was once asked why the beetle-browed Grinch in "How the Grinch Stole Christmas!" (1966) resembled Jones. "It happens," the cartoonist shrugged.

Hammond native Aaron Hartline can vouch for it. Consider Scrat, the scene-stealing squirrel of "Ice Age" and spin-offs. The lead animator at Blue Sky Studios was surprised when a friend identified one of Scrat's meltdowns as Hartline's work.

The giveaway? The acorn-hugger's twitchy eyelid. "When I get angry or concerned, my eye twitches," Hartline admits. If you're an artist at work, "you have to morph into someone else."

The 1993 Hammond High grad should be twitch-free for the interim. He and Blue Sky are drawing raves for the loopy-looney look of "Horton Hears a Who," 20th Century Fox's animated take on Dr. Seuss' 1954 tale.

Never mind Jim Carrey, who voices the role of the title elephant. "The real stars of the movie are the animators, who imbue even the overgrowth in Horton's jungle a certain floppy Seuss-ishness," Variety praised. " ... The visual gags are mostly just great, great fun."

Like TV's "Horton Hears a Who," directed by Jones in 1970, the first computer-generated Seuss film concerns an elephant with a big heart.

When Horton realizes the tiny world of Who-ville exists on a speck of dust, he vows to protect it. His friends brand him crazy, but Horton persists because "a person's a person, no matter how small."

For Hartline, stepping into the shoes of Jones -- a friend of Ted Geisel a la Dr. Seuss -- was a mammoth honor. So was reinventing the Jungle of Nool for a new generation. The Hoosier, two co-supervisors and their crew of 70 animators won Geisel's widow's blessing with footage of Horton splashing in a pool, the book's opening scene.

Audrey Geisel "was very timid at first. I don't think she minded the `Grinch' movie (2000) but I think that she wasn't happy with `Cat in the Hat' (2003). I don't think it lived up to her vision. It took us a while. (to convince her) We actually did the short to prove to them we respect Dr. Seuss and we were going do it the right way."

The Blue Sky staff pored over Seuss's books to absorb his unique style. No nuance was too small. "We would look at how he posed the creatures. A lot of his characters have their heads tilted up and their eyes closed, so we did that. A lot had their hands with two fingers together pinky out, like they're holding a cup of tea, so we did that, too," he said.

Then the real work began, the painstaking construction of the characters and their environment via CGI software. Carrey, Steve Carell and Co. recorded their lines in Los Angeles and the animators designed the corresponding scenes in New York. The Blue Sky crew acted out the roles to help figure out how each character moved and emoted. "It was like a puppet show," Hartline said.

Hard work pay off

Like Horton, Hartline has a sense of duty and persistent streak.

The son of steelworker Nick Hartline and retired Times layout artist Bobbie Rock, Hartline was drawn early to art as a vehicle of self-expression. A champion doodler, he was indifferent to grades as long as he earned "A's" in art.

"Art was my identity," he said.

After graduating from high school, Hartline was accepted to the School of the Art Institute but opted for Columbia College, "which gave me lots and lots of financial aid," he said.

Then life threw a curveball. His girlfriend was pregnant.

The would-be animator was torn. He wanted to provide for his family -- in his chosen field.

"My father as like, 'Why don't you get a job at the mill with me?'" he said. " I walked in and I was so scared , I walked out. And he really stuck his neck out for me. I said, `I could not do this.' I gave myself a year, thinking, `I have a family coming, I've got to give it all or nothing.'"

Hartline talked Columbia into letting him cram his second semester with fine-art and animation courses. Then he landed an entry-level job at Game Refuge, the Homewood, Ill.-based maker of videogames. A three-year stint followed as a modeler at Big Idea Productions, home of Larry the cucumber, Bob the tomato and the "VeggieTales" gang.

"That was the biggest thing in town, in Chicago," the film animator recalled. "It's about vegetables talking about God, which was weird at the time, but I wanted to use the computers." Duties ranged from designing Madame Blueberry to supervising "Larry-Boy! And The Fib from Outer Space!"

His big break came when storyboard freelancer Everett Downing at Big Idea proposed a short about two crime-fighting kids. Hartline pitched the animated film at an industry convention in the late 1990s and Oscar-winning Blue Sky cofounder Chris Wedge ("Bunny") phoned a short time later. "Then I got a call from Blue Sky, saying, `How would you like to work with us?' I said, `I can model.' They said, `No, you can animate. We think you can do it.'"

He could. His first job was building -- or "rigging" -- the face of Manny the Mammoth of "Ice Age" on a computer screen. Then he fine-tuned his expressions. After a year of high-tech grunt work, he became an aminator, rising through the ranks to lead animator.

When his daughter Autumn was little, Hartline never got around to reading Seuss to her. Now, however, he and his wife of four years read the books constantly to their son Jackson, Jackson. And Autumn, now 13, appeared in a production of "Seussical."

He recently took his firstborn, who lives in Oak Park, to "Horton's" premiere but she was unimpressed. "I always wish she'd be, `My dad is the coolest." But she doesn't really care. She's like, `Yeah, that's what you do,'" he said.

Then again, maybe Autumn was like, totally embarrassed. Her father was personally responsible for drawing Vlad, the evil eagle who taunts Horton. Once again, Hartline unconsciously channel himself into his character.

"He supposed to be this villain, a really mean guy. But he really is kind of a cornball, always flubbing his lines," Hartline said. "He tries to do this dramatic Dracula pose but trips on his cape and falls on his face. That's kind of like me. I'm not the most suave guy. I'm just goofy-faced Aaron. My goofiness comes through."