Correspondent Christiane Amanpour reports on the remarkable discovery of a species of monkey that had never been seen before.
Madidi is a place like no other on Earth, where the Andes meet the Amazon, and icy peaks plunge straight down to steamy jungles.
"Imagine a place which starts with that kind of landscape and goes all the way down to lush tropical forests," says British biologist Rob Wallace.
"Finding a new species is always a big deal. Finding a new species of mammal, which many people find more inspirational, is a big deal. And finding a new species of monkey is a huge deal."
This spectacular Bolivian wilderness is Wallace's outdoor laboratory. And after a decade of grueling travel and exploration for New York's Wildlife Conservation Society, Wallace has discovered something most scientists can only dream of.
60 Minutes Wednesday asked Wallace to lead it to the monkeys, on a trip that quickly turned into a remarkable adventure. Just getting there became a vital part of the story.
Dropping through five different climate zones, the trip passed some of the most amazing animals on Earth, like the world's biggest flying creature with a 10-foot wingspan.
"That was an Andean Condor. They're huge, much bigger than I can make with my hands, much bigger," says Wallace. "Sometimes, they fly past really low, and they're incredibly impressive."
The final destination was the largely unexplored national park called Madidi. For 100 miles, only wild rivers cut through Madidi's jungles and gorges.
"It's just completely empty," says Amanpour. "I feel like we're the only people on Earth here."
But it's not the scenery that makes Madidi so extraordinary. Although it's only the size of New Jersey, Wallace believes that in terms of animal life, Madidi may be the richest place on Earth.
"It's a good place to see otters and tapir, cayman, which are South American crocodiles, and Capibara, which are the largest rodents in the world," says Wallace.
"Madidi is the most biological diverse park in the world. If we think of birds, we estimate that eventually there'll be 1,100 species of birds actually in the park, and that's more bird species than there are in the whole of North America, for example. So that makes Madidi very special."
As visitors push even farther into the wilderness, the river gets dangerously shallow. Wallace says the crew has to get out and push. Ladies are excused. The Bolivian park rangers try their best to sound out the hidden dangers, but they can't avoid every obstacle.
After hours of weaving up the Tuichi River, the team finally gets to the wilderness trail that it's been looking for. Now begins the trek through miles of almost impenetrable jungle.
"There's a flat bit, then there's a hilly bit, then there's another flat bit," says Wallace.
"You make it sound so easy," says Amanpour. "It is water and mud and disgusting."
It's just the way the wild pigs like it, and a loud clicking sound is the first clue that they may be in the area.
"That's the clicking of the jaws. It's like a warning sign. So they know something is up; they are beginning to smell us," says Wallace. "The noises we hear, the sort of clacking of the jaws, come from breaking tough nuts, palm nuts, because they've got great big teeth. We've seen herds of 250, 300 animals."
Theoretically, Wallace says, you can get stampeded. And that's exactly what happened. "Everyone always says you have to look for a tree to climb, but so far we've always been OK," says Wallace.
Hours later, the group finally stumbles into Wallace's research station, near where he found the monkey. They are just ahead of a tropical downpour that threatens to spoil the attempt to confirm his discovery.
After nearly four hours on the river, and a grueling four-and-a-half hour trek by foot, the group got up at the crack of dawn to start searching for the new monkey. The rain stopped them.
The deluge stopped by the afternoon, and they were able to start a search in a place where humans are the exotic species.
Have there been times when it's just been too hard?
"Yeah, there are risks. There are things in the forest you are not gonna see in Manhattan," says Wallace. "But there are things in Manhattan that you are not gonna see in the forest, either."
When do you learn to stop looking at your feet and actually look around?
"It takes a while because there are all sorts of hazards," says Wallace. "But after a while, you get used to it, and you can pay attention to what's around you."
There is so much around, including anteaters high up in the trees. And on the canopy above, there are Capuchin monkeys racing across the branches, and a troupe of squirrel monkeys, also feasting on ants.
But all these monkeys are already known to science. The ones being sought are the ones the world has never seen before.
"These monkeys are characterized by having small territories, and they are territorial, so they call every morning, dueting as a pair to defend their territory," says Wallace. "So we're hoping, if we play a cassette that we recorded from another group, that they'll respond and we can figure out where they are. Because they're really secretive."
But all anyone hears is the tape.
"We've got plenty of time," says Wallace. "We just have to keep looking for them."
Finally, the monkeys answer back. It was the first sighting of the new species and it wasn't disappointing - a brilliant orange ball of fur.
"This is a monogamous pair, and they are dueting in response to our music, and that set off another pair," says Wallace.
Among the things that make this new monkey unique is that it mates for life, and the males carry around and shelter their young. They're very close and affectionate.
"They are beautiful monkeys. They're a bit like a teddy bear," says Wallace. "The main characteristic is this golden crown color."
That color was Wallace's first clue that he was looking at a new species, a conclusion now supported by a scientific peer review. The only thing missing is a name for the new monkey.
How important is the discovery?
"Any new discoveries have potential. And it's important that we know what animals are existing, what plants are existing in these places, so that we can make sure that they can be conserved for future generations," says Wallace. "To find a new species of monkey is a dream come true."
Since Wallace discovered the monkey, couldn't he have named it after himself?
"Not really. It's not really considered to be the done thing," says Wallace. "It's bad form. We could have chosen a name. It can be a Latin description of some feature of the animal."
And Wallace wants to do something that's never been tried before. He'll auction off the right to name this monkey to the highest bidder.
"If I can help generate some funding, some significant funding, to make sure that Madidi works, then as far as I'm concerned, that's an easy decision for me to make," he says.
What Madidi needs to make it work is a park management plan that will protect its future. And that will take money, money that Wallace hopes to raise in the auction.
So how much will it be worth to name the little monkey that's been found in Madidi? Wallace and the Bolivian park authorities hope that the promise of scientific immortality will bring a high price.
"There are all sorts of economical and ecological reasons why protected areas are really important," says Wallace. "But I think most importantly, these places are inspirational."