Borrowing heavily from Men in Black and his own Ghostbusters, Ivan Reitman directs the kind of jokey special effects movie in which characters swap wisecracks while getting sprayed with alien goo. Agreeable but instantly forgettable, Evolution treats the possible extinction of humankind as if it were auditions for amateur night at the local comedy club, and the silliness infests the movie even more than the rapidly mutating alien organism infests the Arizona desert. As the two community college science professors who discover the life form, David Duchovny (never more loose and self-satisfied) and crowd-pleaser Orlando Jones alternate uncomfortably between learned reasoning and frat boy razzing. As if any more comic relief were necessary, typecast moron Seann William Scott (Dude, Where's My Car?) is on board to reach a few extra demographics. Julianne Moore shows her softer side as a simpatico government agent who is also a huge klutz. The aliens are a hybrid of typical space alien stuff and dinosaurs, looking good if not actually groundbreaking. A winged creature that's obviously a pterodactyl stand-in carries a young girl through a mall without leaving a scratch -- part of an overall trend to stay light, rather than showing any of the real carnage that might accompany a situation like this. However, since it was released in the era of Tom Green and the Farrelly brothers, there's a fair amount of rectal humor -- both human and alien -- to fill the gross-out quota. Positioned to be a summer blockbuster hit, Evolution shows the strain of trying to be everything to everyone, but it's also difficult to imagine leaving the theater without wearing a goofy grin.