The following script is from "Lion Kings" which aired on Nov. 25, 2012. Lara Logan is the correspondent. Max McClellan, producer.
Dereck and Beverly Joubert have spent more time filming and living among lions in the wild than anyone alive today. The discoveries they've made over 30 years of wildlife filmmaking have challenged conventional wisdom about Africa's big cats.
They've made more than 20 films for National Geographic, where they are "Explorers in Residence."
They live in Botswana in the heart of southern Africa, a country about the size of Texas.
The Jouberts often go long stretches without seeing another human being, but they made an exception for us, and allowed us to join them in a wild place they call home.
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Their films are known for these spectacular cinematic moments. But what distinguishes their work is their belief that all the animals have untold stories which they bring to life in their films.
To get to the Jouberts, we flew to this remote landing strip, but we couldn't land until these wild baboons were cleared from the runway.
It didn't take us long to discover why they decided to make Botswana's Okavango Delta their home. This is one of the last untouched places on earth, a labyrinth of watery channels and rolling savannahs that are home to some of Africa's most beautiful creatures.
But it was the lions that drew the Jouberts here and for most of their lives they have lived among these animals, making some of the greatest wildlife films ever made.
Dereck Joubert: We've spent thousands and thousands of hours with them. We've spent more hours with lions than we've done at university, school, with either of our parents. So this is our family in many ways.
Dereck does the filming and writes the scripts for their movies. Beverly records sound and takes pictures. She's a world class photographer.
Each film takes years to make. They followed this lioness they call Ma di Tau for seven years and they made a movie about her called, "The Last Lions."
[Jeremy Irons: Today, Ma di Tau, "Mother of Lions," earns her name as protector of her young.]
The film told the moving story of her battle to survive alone with her three cubs.
Beverly Joubert: One thing that we have learned, and it's been a hard lesson, is that we can never predict what is going to happen.
Dereck Joubert: First of all, a cub was taken by a crocodile. And then later on, sadly, another one was injured.
Stampeding buffalo had badly wounded the cub. Just as any mother would, you see Ma di Tau go over to it. She tries to take it with her. But there's nothing she can do and her survival instincts take over.
Dereck Joubert: When we filmed it, I sort of said to Beverly, "Let's just cover this, because we'll never use this. This is too, too sad, and too -"
Beverly Joubert: Too traumatic at the time. I mean, it's too traumatic for us to even witness it.
Lara Logan: Tell me about that moment.
Beverly Joubert: It broke our hearts in so many ways because we knew that it was hopeless. I mean a little cub dragging its body, a broken back. What, what could she do?