As years go, 1977 had more than its share of pop culture moments. The TV phenomenon of “Roots,” the sudden death of Elvis Presley, the premiere of “Star Wars,” the advent of the Sex Pistols and the rise of punk rock, and the release of the “Saturday Night Fever” movie and album all come to mind. These events provide plenty of fodder for America’s nostalgia-industrial complex to churn out plenty of 30th anniversary specials in 2007.

So can we really be surprised that TV Land is toasting the 30th anniversary of “Three’s Company” (7 p.m. today, TV Land) with a 24-hour marathon? The 48-episode onslaught includes the pilots of the spin-off series “Three’s a Crowd” (4:30 a.m. Sunday) and “The Ropers” (5 a.m. Sunday).

¢ The line between animation, video games and live-action motion pictures continues to blur. “Hellboy: Blood and Iron” (6 p.m. today, Cartoon Network) is the second animated adaptation/sequel to the 2004 live-action film “Hellboy,” directed by Guillermo del Toro (“Pan’s Labyrinth”). Three actors from the original, including Ron Perlman, Selma Blair and Doug Jones, lend their voices to the animated film. Oscar-nominated actor John Hurt (“The Elephant Man”) also provides the voice of Professor Bloom.

¢ “Mean Girls: The True Hollywood Story” (5 p.m. today, E!) takes a behind-the-scenes look at the making of the 2004 comedy and its star, Lindsay Lohan, and writer Tina Fey (“30 Rock”).

¢ Fans of nature programming dare not miss “Galapagos” (7 p.m. Sunday, National Geographic), a three-hour look at the island chain that is a geological oddity, a biological wonder and evolutionary laboratory.

“Galapagos” traces the islands’ violent volcanic origins as well as their discovery in 1535; their central place in Charles Darwin’s theories; their status as a tourist destination and contemporary efforts to safeguard these natural treasures.

¢ The documentary series “True Life” (8 p.m. Sunday, MTV) looks at three young people coping in their own way with autism. Jeremy, 17, has never been able to speak or make eye contact, but recently he learned to use a machine with a keyboard that can “speak” for him. He’s reached out to his fellow students for the first time and has even planned to invite them to a party.

Autistic savant Jonathan, 19, has sudden bursts of creativity as well as disruptive emotional outbursts. Elijah, 16, has a form of autism that is barely detectable to others. Many simply consider him another quirky teen. He hopes to become a standup comic and use the stage to talk about his life and condition.

Today’s highlights

¢ Scheduled on “Dateline” (7 p.m., NBC): a deadly encounter between a dad and drifter on a desert trail.

¢ Julia Louis-Dreyfus hosts “Saturday Night Live” (10:30 p.m., NBC), featuring musical guest Snow Patrol.

Sunday’s highlights

¢ Scheduled on “60 Minutes” (6 p.m., CBS): soldiers accused of murder in Haditha, Iraq; an interview with Simon Cowell of “American Idol.”