Homo Erectus is a 2007 comedy film about cavemen that was written and directed by Adam Rifkin

Adam Rifkin

Adam Rifkin sometimes credited as Rif Coogan, is an American film director, producer, actor and writer. Rifkin is claimed to belong to a rare breed of film directors that transited from public-access television cable TV to Hollywood.His eclectic career ranges from broad family comedies to cult...

, and starring Giuseppe Andrews

Giuseppe Andrews

Giuseppe Andrews is an American film actor, writer, and director known for his roles as Lex in the 1999 film Detroit Rock City, a bizarre sheriff's deputy in Cabin Fever , a small role in Never Been Kissed , as well as appearances in The Smashing Pumpkins videos "1979" and "Perfect".Andrews has...

, Gary Busey

Gary Busey

William Gary Busey , best known as Gary Busey, is an American film and stage actor and artist. He has appeared in a large variety of films, as well as making regular appearances on Gunsmoke, Walker, Texas Ranger, Law & Order, and Entourage...

, David Carradine

David Carradine

David Carradine was an American actor and martial artist, best known for his role as a warrior monk, Kwai Chang Caine, in the 1970s television series, Kung Fu, which later had a 1990s sequel series, Kung Fu: The Legend Continues...

, Ron Jeremy

Ron Jeremy

Ronald Jeremy Hyatt , usually called Ron Jeremy, is an American pornographic actor. Nicknamed "The Hedgehog", he was ranked by AVN at number one in their "The 50 Top Porn Stars of All Time" list...

, Ali Larter

Ali Larter

Alison Elizabeth "Ali" Larter is an American actress. She is perhaps best known for playing the dual roles of Niki Sanders and Jessica Sanders on the NBC science fiction drama Heroes as well as her guest roles on several television shows in the 1990s.Larter's screen debut came in the 1999 film...

, Hayes MacArthur

Hayes MacArthur

Hayes MacArthur is an American stand-up comedian, actor and writer.-Early life:MacArthur was born in Chicago, Illinois. He attended Deerfield Academy and received a B.A. in Government from Bowdoin College in Brunswick, Maine. He has studied at the Groundlings Theater Company and Atlantic Theater...

, Adam Rifkin

Adam Rifkin

Adam Rifkin sometimes credited as Rif Coogan, is an American film director, producer, actor and writer. Rifkin is claimed to belong to a rare breed of film directors that transited from public-access television cable TV to Hollywood.His eclectic career ranges from broad family comedies to cult...

, and Talia Shire

Talia Shire

Talia Shire is an American actress most known for her roles as Connie Corleone in The Godfather films and Adrian Balboa in the Rocky series.-Personal life:...

. It premiered at the 2007 Slamdance Film Festival

2007 Slamdance Film Festival

The 2007 Slamdance Film Festival took place in Park City, Utah from January 18 to January 27, 2007. It was the 13th iteration of the Slamdance Film Festival, an alternative to the more mainstream Sundance Film Festival...

 in January 2007. It was released on DVD in America as National Lampoon's Stoned Age.
Ishbo (Rifkin) is the younger son of Mookoo (Carradine), the leader of a tribe of cavemen. Ishbo is smarter than most of his tribesmen, but awkward and nerdy, living in the shadow of his much more physically impressive brother Thudnik (MacArthur).