UPDATE 1-Will Smith, Chipmunks send box office soaring

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By Dean Goodman

LOS ANGELES, Dec 16 (Reuters) - The last man on Earth was first at the weekend box office in North America as Will Smith's sci-fi thriller "I Am Legend" crushed the competition with a record opening, distributor Warner Bros. said on Sunday.

The film brought in $76.5 million and was the seventh consecutive chart-topper for the versatile Smith. It combined with a surprisingly strong $45 million debut for "Alvin and the Chipmunks" to end the box office's five-week losing streak, even as severe winter storms across the Midwest and Northeast hurt ticket sales.

"I Am Legend" ranks as the best December opening of all time, beating the $72.6 million start for "Lord of the Rings: Return of the King" in 2003, the Time Warner Inc (TWX.N)-owned studio said. The studio said it had hoped for an opening in the mid-$40 million range.

Smith plays a military virologist who has survived a human-made virus that apparently killed everyone else on the planet. Music video veteran Francis Lawrence directed the film, working from an adaptation of a 1954 novel by Richard Matheson. It was originally envisaged as a vehicle for Arnold Schwarzenegger and director Ridley Scott in the early 1990s.

"Alvin and the Chipmunks" squealed its way to No. 2 with $45 million, more than doubling the expectations of its distributor, Twentieth Century Fox.

The film combines real actors, led by Jason Lee, with animated renderings of Alvin, Simon and Theodore, the beloved helium-voiced singing trio. The News Corp NWSa.N-owned studio said the film played strongly with family audiences, as expected, but also drew plenty of young-adult viewers.

OVERALL SALES UP