Sometimes I like just to stand on the top of the first dune, looking at people's reaction.

People arrive and... Wow.

The first time that I came here, I was around 12 years old.

It was shocking.

It was a feeling like to be in another planet.

It looks like a desert, but Lençóis Maranhenses gets more rain than Scotland or London, which is around 1600 millimeters [63 inches] a year.

So it's not a desert- it's something else.

Lençóis Maranhenses, on the northeast coast of Brazil, sits at the intersection of three biomes- a rare overlap that supercharges biodiversity.

Here, a field of dunes spreads across 350 square miles, and every year these mountains of sand migrate up to 80 feet.

Then during the rainy season, thousands of lagoons appear, many big enough to swim in.

So what makes this surreal environment possible?

And why, even after 2 million years in existence, does it still feel so mysterious?

Lençóis Maranhenses is the biggest field of dunes in South America.

Between these dunes, during the rainy season the water level rises and they form lagoons.

You can never see Lençóis Maranhenses twice because everything is changing all the time.

Strong movements of sand and water changing the shapes and the compositions of the lagoons.

I spent almost like a year camping and living in tents around the park and surveying amphibians and reptiles.

This opportunity changed my view of life and helped to forge the biologist that I am today.

Some visitors arrive there and wonder why the water just doesn't sink.

Underneath the field of dunes, there is a rock which traps water so it doesn't keep sinking forever.

So let's imagine there is a bathtub.

When it rains, the water level starts to rise.

And then you can see the water in the holes in between the dunes, so you can see the lagoons formed.

And then in the dry season, the water evaporates.

The water level starts to go down again until it gets here.

The water is still there.

The water is still there.

People cannot see it, but it is still there.

If this year, a lagoon is in a certain place in the next year, it will move.

Because where the lagoon is formed, the dunes will bury that lagoon.

And next year, a new lagoon will emerge further ahead.

Here, an unusually large tide range creates a wide beach at low tide.

Strong winds lift the fine sand and blow it inland to build new dune ridges.

The winds come mainly from the same direction.

The sand gets dry and then it can be carried by this strong wind.

They measured the size of the grains.

It's so little.

The sand is so soft, it's so loose that it flows down the hill like water.

It's beautiful.

The wind is constantly redrawing paths, so locals follow wind and ridgelines, not maps.

I was born and raised here, in Ponta do Mangue.

My parents were born here, my grandparents were born here and we've been living here this whole time.

Sometimes we go out in the morning, and it's windy, the dune is flat.

When we return later in the day, the dune has a different shape.

You have to be very careful, sometimes we get lost.

The wind erases all the car tracks.

Out of nowhere, it creates a dune in the middle of another.

Last week, we took a wrong turn and we kept going.

Later we realized that we were in the wrong path.

Then we came back again, so we could continue.

They call it the desert that breathes because of the dunes, the movement of the dunes.

Everything is destroyed and rebuilt every single year.

In the region of Lençóis everything is mixed.

There are some animals that occur just there.

And salt marshes, very far from the ocean, different from almost all the others that exist in the world that usually occur very close to the beach because it needs this salt.

We have a turtle, which is Pininga.

It's a water tiger turtle.

It's an endemic species.

And the park plays an important role for its conservation, because it doesn't exist anywhere else.

And this animal is known to rest, digging underneath the dunes.

So it reduces its metabolism, waiting for the next rainy season.

The fish have a life cycle shorter than one year.

They leave the eggs that are resistant to this dryness.

And when the water comes, everything comes to life again.

We are going to a world of extremes.

Lençóis, it's a micro-laboratory; as we increase our knowledge, we might find ideas that may be useful on the perspective of a climactic emergency.

Since we live near the dunes, sometimes we have to move.

Since we live near the dunes, sometimes we have to move.

Since we live near the dunes, sometimes we have to move.

Since we live near the dunes, sometimes we have to move.

Since we live near the dunes, sometimes we have to move.

My father used to live among those dunes over there.

The dune kept growing.

In our case, in about three, four years, I think we'll have to move, because the dunes are getting closer and throwing sand.

When the lagoons dry up we take the fish from the ponds and put them in the ones that have more water so they can survive a little longer, otherwise, they will die of drought.

so they can survive a little longer, otherwise, they will die of drought.

When I close my eyes and I think about Lençóis Maranhenses, the first thing that comes to my mind is a dragonfly, flying over a lagoon... There are white flowers, their roots dancing in the water.

It's a place that can really change people's mind and soul and heart.

And they say, "for the first time I'm breathing."

Very special place.

Sorry.

When I pass away, I'd like them to burn me and put my ashes moving from lakes to lakes.

Moving with the wind, with the water.

To be part of it, forever.