Question: In what decade did the director of the film The Day of the Dolphin begin his career? 

full_context: Document 1: Dog Day Afternoon: Dog Day Afternoon is a 1975 American crime drama film directed by Sidney Lumet, written by Frank Pierson, and produced by Martin Bregman and Martin Elfand. The film stars Al Pacino, John Cazale, Charles Durning, Chris Sarandon, Penelope Allen, James Broderick, Lance Henriksen, and Carol Kane. The title refers to the sultry "dog days" of summer.
Document 2: Dolphin Encounters: Dolphin Encounters is a natural seawater dolphin facility located on Blue Lagoon Island, (Salt Cay), Nassau, Bahamas. The company started as a rescue facility in 1989. The beach scenes in the movie "Splash" were taped on Blue Lagoon Island and the facility houses Atlantic bottlenose dolphins, ("tursiops truncatus") and California sea lions. Dolphin Encounters is owned and operated by a local family. The facility has received a Cacique Award from the Bahamas Ministry of Tourism. In 2003, Dolphin Encounters and Project B.E.A.C.H. received the Cacique Award from the Bahamas Ministry of Tourism.
Document 3: Close Encounters of the Third Kind: Close Encounters of the Third Kind is a 1977 American science fiction film written and directed by Steven Spielberg, and starring Richard Dreyfuss, Melinda Dillon, Teri Garr, Bob Balaban, Cary Guffey, and François Truffaut. It tells the story of Roy Neary, an everyday blue-collar worker in Indiana, whose life changes after an encounter with an unidentified flying object (UFO).
Document 4: Mick Napier: Mick Napier (born December 12, 1962) is an American director, actor, teacher and author living in Chicago. He is the founder and artistic director of the Annoyance Theatre and an award-winning director at The Second City. He has directed Stephen Colbert, Tina Fey, Rachel Dratch, Horatio Sanz, Nia Vardalos, Andy Richter, Jeff Garlin, and David Sedaris, amongst others.
Document 5: Three Days of the Condor: Three Days of the Condor (stylized on the poster art as 3 Days of the Condor) is a 1975 American political thriller film directed by Sydney Pollack and starring Robert Redford, Faye Dunaway, Cliff Robertson, and Max von Sydow. The screenplay by Lorenzo Semple Jr. and David Rayfiel was adapted from the 1974 novel "Six Days of the Condor" by James Grady. The main point of variance from novel to film lies in the presentation of the CIA. In Grady's book, a rogue element within the Agency is motivated by drug-running greed. In the film, the same individuals act with equal ruthlessness to hide a project intended to protect long-term national interests.
Document 6: The Silent World: The Silent World (French: Le Monde du silence ) is a 1956 French documentary film co-directed by the famed French oceanographer Jacques-Yves Cousteau and a young Louis Malle. "The Silent World" is noted as one of the first films to use underwater cinematography to show the ocean depths in color. Its title derives from Cousteau's 1953 book "". It was released in the United States by Columbia Pictures.
Document 7: Mike Leigh: Mike Leigh OBE (born 20 February 1943) is an English writer and director of film and theatre. He studied at the Royal Academy of Dramatic Art (RADA) before honing his directing skills at East 15 Acting School and further at the Camberwell School of Art and the Central School of Art and Design. He began as a theatre director and playwright in the mid-1960s. In the 1970s and 1980s his career moved between theatre work and making films for BBC Television, many of which were characterised by a gritty "kitchen sink realism" style. His well-known films include the comedy-dramas "Life is Sweet" (1990) and "Career Girls" (1997), the Gilbert and Sullivan biographical film "Topsy-Turvy" (1999), and the bleak working-class drama "All or Nothing" (2002). His most notable works are the black comedy-drama "Naked" (1993), for which he won the Best Director Award at Cannes, the Oscar-nominated, BAFTA and Palme d'Or-winning drama "Secrets & Lies" (1996), the Golden Lion winning working-class drama "Vera Drake" (2004), and the Palme d'Or nominated biopic "Mr. Turner" (2014). Some of his notable stage plays include "Smelling A Rat", "It's A Great Big Shame", "Greek Tragedy", "Goose-Pimples", "Ecstasy", and "Abigail's Party".
Document 8: Island of the Blue Dolphins: Island of the Blue Dolphins is a 1960 children's novel written by Scott O'Dell and tells the story of a young girl stranded alone for years on an island off the California coast. It is based on the true story of a Nicoleño Native American left alone for 18 years on San Nicolas Island during the 19th century.
Document 9: Mike Nichols: Mike Nichols (born Mikhail Igor Peschkowsky; November 6, 1931 – November 19, 2014) was an American film and theatre director, producer, actor and comedian. He was noted for his ability to work across a range of genres and an aptitude for getting the best out of actors regardless of their acting experience. Nichols began his career in the 1950s with the comedy improvisational troupe, The Compass Players, predecessor of The Second City, in Chicago. He then teamed up with his improv partner, Elaine May, to form the comedy duo Nichols and May. Their live improv acts were a hit on Broadway resulting in three albums, with their debut album winning a Grammy Award.
Document 10: The Committee (improv group): The Committee was a San Francisco-based improvisational comedy group founded by Alan Myerson and Jessica Myerson, formerly known as Irene Ryan, Irene Riordan and now known as Latifah Taormina. The Myersons were both alums of The Second City in Chicago. The Committee opened April 10, 1963 at 622 Broadway in a 300-seat Cabaret theater that used to be an indoor bocce ball court in San Francisco's North Beach. Garry Goodrow, Hamilton Camp, Larry Hankin, Kathryn Ish, Scott Beach and Ellsworth Milburn were the cast. Jerry Mander handled the group's PR, and Richard Stahl, who later joined the improv troupe, was its first company manager. Jessica Myerson joined the company in May. Arthur Cantor took the company to Broadway in New York in 1964 for a limited engagement at the Henry Miller Theater. This occasioned a second group to hold the fort in San Francisco. Morgan Upton, Peter Lane, Leigh French, Chris Ross, Howard Hesseman (who used the name Don Sturdy), Nancy Fish, Peter Bonerz and Carl Gottlieb became the mainstays of the San Francisco troupe. Roger Bowen, a founding member of both The Compass Players and The Second City, joined in 1966. John Brent, co-creator with Del Close of the "How to Speak Hip" album and a bit player in many movies ("Catch-22", "American Graffiti", "More American Graffiti", "Bob & Carol & Ted & Alice", "Steelyard Blues", "Porklips Now"), was also a member.
Document 11: Mel Brooks: Mel Brooks (born Melvin Kaminsky; June 28, 1926) is an American actor, writer, producer, director, comedian, and composer. He is known as a creator of broad film farces and comic parodies. Brooks began his career as a comic and a writer for the early TV variety show "Your Show of Shows". He became well known as part of the comedy duo with Carl Reiner in the comedy skit "The 2000 Year Old Man". He also created, with Buck Henry, the hit television comedy series "Get Smart", which ran from 1965 to 1970.
Document 12: Mike Nichols (author): "For other persons named Mike Nichols, see Mike Nichols (disambiguation)."
Document 13: Soylent Green: Soylent Green is a 1973 American science fiction thriller film directed by Richard Fleischer and starring Charlton Heston and Leigh Taylor-Young. Edward G. Robinson appears in his final film. Loosely based on the 1966 science fiction novel "Make Room! Make Room!" by Harry Harrison, it combines both police procedural and science fiction genres; the investigation into the murder of a wealthy businessman and a dystopian future of dying oceans and year-round humidity due to the greenhouse effect, resulting in suffering from pollution, poverty, overpopulation, euthanasia and depleted resources.
Document 14: The Day of the Dolphin: The Day of the Dolphin is a 1973 American science-fiction thriller film directed by Mike Nichols and starring George C. Scott. Based on the 1967 novel "Un animal doué de raison" (lit. "A Sentient Animal"), by French writer Robert Merle, the screenplay was written by Buck Henry.
Document 15: Mike Nichols: American Masters: Mike Nichols: American Masters is a 2016 documentary film directed by Elaine May about the life of Mike Nichols broadcast on the PBS series "American Masters". It is derived from a lengthy interview with Nichols conducted by producer Julian Schlossberg. Brian Lowry of "Variety" has called it "the last memorable Nichols-May collaboration." Richard Brody said that although it is not a major contribution to May's life's work, it "is nonetheless distinctive in its sparseness, its fixed and almost obsessive concentration on Nichols’s face and voice... [it's] May’s highest tribute to Nichols."
ground_truth: 1950s