The 4th of July box office of 2009 saw a tie between alien robots and prehistoric creatures, as the "Transformers" sequel and the new "Ice Age" film were dead even according to estimates on Sunday (July 5).

While final numbers on Monday will show which actually came in first, initial numbers indicate that "Transformers: Revenge of the Fallen" and "Ice Age: Dawn of the Dinosaurs" pulled in $42.5 million a piece over the weekend for a tie.

According to box office experts, it's rare that box-office rankings are so close, particularly in summer, when movies typically have huge opening weekends then trail off to make way for the next blockbuster.

After debuting at #1 last week with $201.2 million, "Revenge of the Fallen" held up well during its second weekend, while animated sequel "Ice Age" packed in family crowds. After 12 days "Transformers" has earned $293.5 million at the box office, making it the year's highest-grossing movie. It's the sequel to the first film, reuniting human stars Shia LaBeouf and Megan Fox with shape-shifting robots in a war against evil machines.

The other wide release this weekend was Universal's crime saga "Public Enemies," starring Johnny Depp and Christian Bale. It debuted a solid #3 with $26.2 million.

At #4 is Sandra Bullock's "The Proposal" with $12.7 million; "The Hangover" grabbed #5 with $10.4 million taking its total over $200 million; #6 was "Up" with $6.5 million; #7 is "My Sister's Keeper" with $5.2 million; #8 was "The Taking of Pelham 1 2 3" with $2.5 million; and the last top 10 spots are held by "Night At the Museum" and "Year One" with $2.1 million a piece.

Next weekend, the Sacha Baron Cohen comedy "Bruno" hits theaters, as well as "I Love You Beth Cooper" starring Hayden Panettiere of the hit TV series "Heroes".