This segment originally aired March 20, 2005. It was updated on June 8, 2007.
The tsunami may have lasted only a couple of hours, but it will not go away. New casualties are still being discovered: Thais, Swedes, Sri Lankans, and Indonesians. The death toll has topped 175,000. And there's more than 125,000 still missing and presumed dead.
But there's one group who live precisely where the tsunami hit hardest who suffered no casualties at all. They are the sea gypsies of the Andaman Sea, or as they call themselves, the Moken.
They've lived for hundreds of years on the islands off the coast of Thailand and Burma. They are, of all the peoples of the world, among the least touched by modern civilization.
And, as correspondent Bob Simon reports, they miraculously survived the tsunami because they knew it was coming.
It's their intimacy with the sea that saved the Moken. They're born on the sea, live on the sea, die on the sea. They know its moods and motions better than any marine biologist. They're nomads, constantly moving from island to island, living more than six months a year on their boats.
At low tide, they collect sea cucumbers, and catch eels. At high tide, they dive for shellfish. They've been living this way for so many generations that they've become virtually amphibious.
Kids learn to swim before they can walk. Underwater, they can see twice as clearly as the rest of us, and by lowering their heart rate, can stay underwater twice as long. They are truly sea urchins.
60 Minutes discovered a Moken village on an island two hours by speedboat from the coast of Thailand. It had become something of an exotic tourist Mecca before the tsunami.
A Bangkok movie star and amateur photographer named Aun was here on Dec. 26, 2004, taking pictures of Moken village life, when someone noticed the sea receding into the distance.
Aun's pictures showed the Moken on the beach crying. Did she have any idea why they were crying? "I feel like they know what bad will happen," says Aun.
Her pictures also show the Moken fleeing towards higher ground long before the first wave struck. Aun pointed out how high the water first came. And that was just the first wave. The worst was yet to come, and the Moken knew because of signs from the sea.
It wasn't only the sea that was acting strangely. It was the animals, too. On the mainland, elephants started stampeding toward higher ground. Off Thailand's coast, divers noticed dozens of dolphins swimming for deeper water. And on these islands, the cicadas, which are usually so loud, suddenly went silent.
Saleh Kalathalay, a skilled spear-fisherman who was on a different part of the island, also noticed the silence. He ran around warning everyone.
Kalathalay brought the skeptics to the water's edge, where they, too, saw the signs. Eventually, everyone, the Moken and the tourists, climbed to higher ground and were saved. But there's nothing left in the village.
Why does Kalathalay think the tsunami happened? "The wave is created by the spirit of the sea," says Kalathalay. "The Big Wave had not eaten anyone for a long time, and it wanted to taste them again."