It's been 50 years since Joy and George Adamson adopted a lion cub in Kenya.

Her name was Elsa and she became the major character in the book, "Born Free" by Joy Adamson. A popular movie followed starring Virginia McKenna as Joy and McKenna's husband, Bill Travers, as George.

But the star of the piece was Elsa and it marked a new understanding of the relationship between wild animals and humans - a combination that nowadays people often - to their detriment - take for granted.

For those too young to remember the story, PBS is offering a documentary on "Nature" Jan. 9. "Elsa's Legacy: the 'Born Free' Story" not only brings us up-to-date on the status of animals in Africa, it shows us how it used to be, says documentary filmmaker Sacha Mirzoeff.

"It instructs us a little bit about our desire to connect with nature, to have a sense that we still can be part of the natural world and have an understanding, and that the relationships with wild animals are possible and that individuals, animals should be seen just as that, that there's no such thing as generic lion, elephant or monkey," he says.

McKenna says working with the young lions in "Born Free" (there were several) made her far more sensitive and pro-active to the needs of the graceful beasts who are often exploited by man.

"We started in 1984 because of the death of an elephant at London Zoo in '83, an elephant we had worked with in a film at the end of the '60s that we knew.

"And my husband, Bill, and I were so shattered by the death of this wonderful teenage elephant that we decided that her death should not be in vain.

"And we started our organization in '84, which was then known as Zoo Check because, at the beginning, our focus was totally on the situation of wild animals in captivity, whether it was the circus or the zoo," she says.

"And we started to investigate, not only in our own country, but further afield, the damage that so many captive situations can do to wild animals when they can't cope with their environment.

"But, as we developed, thanks, I have to say, mainly to the work of our eldest son Will - Will Travers - we began to work with problems that they face in the wild as well.

"And that, today, probably forms at least half of the work we do: wild animals in trade, wild animals who are poisoned because they are attacking villagers and villages and damaging crops, reduction of habitat, of sport hunting.

"For me always and for my husband until his death, our focus was on the captive wild animal because that is truly what the experience of working with the 'Born Free' lions, most of which were sent to zoos and safari parks when the film was over - only three were given to George to return to the wild, and that betrayal that we felt at the time spurred us on over the years."

McKenna thinks the Adamsons led the way.

"They were pioneers just as Jane Goodall was for chimps, Dian Fossey was for gorillas and Biruta Galdikas for orangutans. They were the pioneers that started us thinking about animals as individuals.

"Before that, you know, it was lions and tigers and elephants and gorillas, whatever, but we thought of animals collectively. We didn't do that in our own homes with our cats and dogs, but we did do it for wild animals because we didn't seem to understand, until this new thinking came about, that animals, too, have feelings," she says.

"They have many feelings that we have. We are, after all, human animals. They feel jealousy. They feel pain. They can suffer. They can feel joy. They can feel a lot of the things, not all of the things perhaps, that we feel.

"And it was through the inspirational work and understanding of people that I just mentioned that we started to think much more deeply ourselves about those issues.

"And, of course," she continued, "once you see an animal as an individual, you can't bear for it to suffer. You can't bear to see it when it's deprived in a zoo cage or in a circus ring. It's truly deeply shocking and deeply sad, and you've got to try and do something about it.

"And because we were both action people, we thought it's no good us sitting at home and saying 'Isn't it terrible?' We want to get out and try and do something."