LOS ANGELES: Animated romp "Ice Age: Return of the Dinosaurs" shot to the top of the North American box office in its first week in theatres, but had to share the spot with "Transformers: Revenge of the Fallen," according to earnings estimates released Sunday.

The kid-friendly "Ice Age," featuring the voices of Queen Latifah and Dennis Leary as prehistoric animals who discover a lost jungle inhabited by dinosaurs, took 42.5 million dollars in box office receipts over the three-day weekend.

That was exact same amount earned over that period by Michael Bay's "Transformers," according to box office tracker Exhibitor Relations.

The high-action, special-effects laden follow up to 2007's first Transformers movie was panned by critics, but stormed straight to the top of the box office when it was released last week.

In third place was new release "Public Enemies," starring Johnny Depp as notorious US gangster John Dillinger, which pulled in 26.1 million dollars in its first week.

Meanwhile, fourth place went to "The Proposal," a romantic comedy starring Sandra Bullock as a pushy boss who marries her assistant for a US visa, continued to draw audiences, taking in 12.8 million dollars in its third week in theatres.

"The Hangover," a raucous comedy about the fallout from a Las Vegas bachelor party, came in fifth place with in 10.4 million dollars this week, bringing its four-week total to 204.2 million dollars -- a massive gain on its 35-million-dollar budget.

Pixar's latest animated feature "Up," which tells the heartwarming story of a grumpy old man who finds adventure in Latin America, stayed strong into its sixth week in theatres for sixth place.

The hugely successful movie added another 6.5 million dollars to the 264.9 million it has earned since its release.

In its second week in theaters "My Sister's Keeper," starring Cameron Diaz, slipped down in the rankings with box office receipts of 5.3 million dollars, claiming the seventh spot.

"The Taking of Pelham 123," a remake of a classic 1974 movie about a subway hijacking, also fell one spot to eighth place, bringing in 2.5 million dollars in its fourth week in theatres.

Rounding out the top ten were "Year One," a comedy about prehistoric hunter-gatherers, in the ninth spot, earning 2.1 million dollars; and "Night at the Museum: Battle at the Smithsonian" for tenth.

The sequel to 2006's "Night at the Museum," which stars Ben Stiller and Amy Adams, also earned 2.1 million dollars, bringing its seven-week earnings to 167.8 million dollars.