LOS ANGELES - Lily Tomlin's admiration for elephants began when she met Ruby and Billy.

The zoo dwellers also sparked her desire to help improve the lives of elephants in captivity and the chances for survival of those in the wild. "An Apology to Elephants," a documentary produced and narrated by Tomlin, is one result. It debuted this week on HBO.

"I had done some animal activism" and donated money, Tomlin said, but becoming enlightened about elephants prompted her to focus on their plight.

The film is an unabashed polemic, calling for improved treatment of elephants in zoos and an end to the use of the animals as entertainment, which the film contends must invariably involve abuse. Circus operators do not have a say, although a zoo that has overhauled its elephant habitat weighs in.

"An Apology to Elephants" also outlines the animal's importance to ecosystems and the dangers faced by wild African and Asian elephants, including habitat destruction and poachers after their highly marketable tusks.

Last month, leading conservation groups warned that the illegal ivory trade is growing and is hastening the decline of Africa's already endangered elephant population.

"The elephants became so symbolic to me, the evidence (of their treatment) so clear, and I wanted to tie it together and show how inured we are to that around the planet," said Tomlin, an Oscar-nominated actress ("Nashville") and comedian.

Feld Entertainment, the parent company of Ringling Bros. and Barnum & Bailey Circus, said the film misrepresents its practices.

"Clearly, it's a distortion of the animal care we provide 24 hours a day, seven days a week for this magnificent species. We have a team of animal care professionals and veterinarians who spend their lives caring for these animals," said spokesman Stephen Payne.

The film also failed to include the company's conservation efforts that Feld said are international and done in concert with zoos and researchers. "As opposed to people who make one-off documentaries or protest, we put our money where our mouth is," Payne added.

The film's images are dramatic, some by contrast: We see a line of elephants silhouetted majestically against an orange African sun as well as a solitary pachyderm confined within a zoo enclosure. There also are disturbing shots, including elephants prodded by sharp-edged rods and footage of the 1903 death of a Coney Island elephant that, according to the film, had turned violent because of abuse. Thomas Edison agreed to electrocute the animal named Topsy to illustrate a certain type of current.

The film spotlights those who are working for elephants today, including the Oakland Zoo, which has implemented new methods of managing the animals, including more space to roam, and a Northern California wild animal sanctuary that helps remove elephants from circuses and zoos.

The grounds are home to elephants Gypsy and Wanda, who performed for the same circus before being split up. When the pair ended up 20 years later at the sanctuary, they "went crazy and are inseparable," said Pat Derby, the former animal trainer who co-founded the Performing Animal Welfare Society, or PAWS, which operates the sanctuary.

Their new life, in nature and without the demands of performing, represents her dream, Derby says in "An Apology to Elephants." The film is dedicated to Derby, who died in February of cancer at age 69.

"Knowing they have some days or even years of safety and peace and dignity, that's the big reward," said Derby in the documentary directed by Amy Schatz.

Tomlin said her hope is that people take heed of what elephants face. Her narration, written by her longtime partner, Jane Wagner, is measured and eloquent, but she's passionate in conversation as she decries "inequity and injustice and suffering" and encourages others to get involved.

"The first thing is to be conscious of the ivory trade. Don't foster anything like admiring ivory objects or people wanting them," she said. "Just to have that consciousness affects the movement of things. It takes years, but it's like getting people to wear seatbelts."

Lynn Elber is a national television columnist for The Associated Press.