“Evolution” has a PG-13 rating for crude and sexual humor and some mildly scary sci-fi action. This rating seems curious because most of those older than 13 will probably be too mature or too bored with this film.

The movie is peppered with snot, crotch and anal references and gags that are too frequent to be humorous to most adults.

Ira Kane (David Duchovny) and Harry Block (Orlando Jones) are community college professors and amateur scientists who discover alien life on a meteor that crashes in the Arizona desert near wanna-be fireman Wayne Green (Seann William Scott).

The aliens divide, split and multiply so rapidly that 200 million years of evolution take place in a few hours and the aliens threaten to overtake the world in only a few weeks.

The government and military, complete with bumbling, sympathetic fellow scientist Allison Reed (Julianne Moore), are then brought in to investigate.

The oozing, splattering and flatulent ghosts from director Ivan Reitman’s 1984 hit “Ghostbusters” have been replaced by aliens in “Evolution.” Unfortunately, the aliens are on screen too infrequently to hold much interest.

Dan Aykroyd has a token role as the governor of Arizona, which makes comparisons to “Ghostbusters” almost unavoidable.

In the 1984 film, comedians Aykroyd, Bill Murray and Harold Ramis played scientists battling ghosts. In “Evolution,” dramatic actors Duchovny and Moore and 7UP spokesperson Jones play scientists battling aliens.

Duchovny (“X-Files”) and Moore (“Hannibal,” “Magnolia,” “Boogie Nights”) are known more for their dramatic roles than their comedic talents and seem bogged down by an unoriginal script and jokes that fall flat.

Scott (“American Pie,” “Road Trip”) plays an obnoxious, goofball character who manages to continuously reference private parts and bodily functions throughout the film.

Special effects that were original and cutting edge in 1984 are replaced by poor effects that seem tired compared to more recent sci-fi movies like “Jurassic Park” and “Men In Black.”

One scene, where a cute alien transforms into an ugly, mean one, seems almost like a direct rip-off from a similar gag in the recent sci-fi comedy “Galaxy Quest.”

There is no suspenseful buildup to the movie because the plot is telegraphed far in advance and the ending seems cursory. The only hope for this film is if children younger than 13 manage to coerce their parents into taking them. If parents are looking for a film for the kids they would be better served taking them to see “Shrek” or renting “Ghostbusters.”