The seas of Avatar: James Cameron on the real science behind his fictional world

James Cameron is diving into the deep: this time, into the oceans of an alien world. The filmmaker and ocean explorer’s latest science-fiction epic, Avatar: The Way of Water, promises to transport viewers to the vibrant aquatic ecosystems of a world 25 trillion miles from Earth, with a documentary’s level of detail.

The new film extends the story of the 2009 blockbuster Avatar, which told the tale of a habitable alien moon called Pandora, the blue-skinned humanoids who live there (the Na’vi), and the conflict that arises when space-faring humans try to colonize and mine the world, regardless of the environmental havoc they wreak. In the first film, the Na’vi of the world’s rainforests fight to protect their home, aided by human soldiers and scientists sympathetic to their cause.

This time around, Cameron is exploring the waters of Pandora, and he brings a lifetime of experience with him. The creative mind behind The Abyss and Titanic, and the executive producer of National Geographic’s Secrets of the Whales, is also a National Geographic Explorer at Large. In 2012, Cameron completed the first solo dive to the bottom of the Mariana Trench in the Deepsea Challenger expedition.

To tell the story of Pandora’s undersea life, Cameron and his team dreamed up a menagerie at once alien and familiar. Pandoran amalgams of pufferfish and lionfish drift beside recognizable reefs. Life-forms that would fit right in with the critters of Earth’s ancient oceans skitter and undulate. Long-necked steed called ilu resemble the extinct marine reptiles known as plesiosaurs. Skimwings—gigantic alien crosses of gar and flying fish—act as Na’vi war mounts. And then there’s the tulkun: titanic, highly intelligent analogues to Earth’s whales.

What inspired these creatures, and how did Cameron and his team bring them to life? National Geographic recently spoke with Cameron from New Zealand about the science and technology of The Way of Water. (The Walt Disney Company is majority owner of National Geographic Partners. It also owns 20th Century Studios, the distributors of Avatar: The Way of Water.) 

This interview has been condensed and edited for clarity.

We started our journey into Pandora on land, and as this movie’s title suggests, we’re making our way to the coastline and into the deep. Why go to the water?

It’s no secret that as an ocean explorer now, as an avid scuba diver for many years before that, and as a fan of ocean exploration when I was a kid, I’ve had this romance with the ocean my entire life. That has involved spending thousands of hours underwater in shallow settings and hundreds of hours underwater in deep settings—as deep as the deepest place on the planet—and many dives to Titanic. They say, ‘Write what you know,’ and I know a lot about the ocean, and I love the ocean. And I thought, why not put two things that I love together? I wanted this film to be about the way of water: how the place where life was born on Earth evolved over time, and the wonders that we see there even today—even in its damaged state, thanks to us humans.

We live in a shifting baseline, where the ocean as we see it today is not what it once was. The film was also an opportunity to show us what our oceans might have looked like 300, 400, 500 years ago, before we really got busy toward an industrial civilization. If people see this film, and aside from the drama of the Sully family [the film’s protagonists] and the relationships and all these big, dramatic conflicts, if they just love the underwater experience—and they love that sense of the profusion of life and the magic and mystery—then maybe it will reconnect them with what we are presently losing here on this planet.

What were some of your inspirations as you were fleshing out both this aquatic ecosystem and the alien culture that lives within it?

We have these people called the Metkayina, a clan that’s spread out across a large number of villages. The Metkayina are a kind of a regional, Indigenous culture: They diverged from the land-based forest Na’vi [of the first film] probably tens of thousands of years ago and have physically adapted more to the ocean. Their tails are actually used for propulsion as in the way that they swim, like seals and otters. They’re air-breathers, so they’ve adapted to being able to hold their breath for long periods of time. They have nictitating membranes, kind of like crocodiles and owls, to protect their eyes when they’re entering the water at high speed as they’re riding [ilu], these creatures that they’ve tamed and have this symbiotic relationship with.

They also have a symbiotic culture with an intelligent species of ocean air-breathers: big animals that we would probably take a glance at and say, Oh, that’s a whale. But, of course, it’s not a whale—it’s the Pandora version, which is called a tulkun. The tulkun are actually a very advanced society, even though their advancements are all mental. They have no technology because they have no manipulating hands as we do. They rely on the Na’vi for anything that requires that kind of physical manipulation, but they’re quite advanced mentally: They have complex language, they have mathematics, they have music, and so on.

It was an interesting journey for me to do the National Geographic limited series Secrets of the Whales because that showed that the cetaceans that live here on planet Earth—the real ones—actually have a more advanced culture than we had previously thought, in terms of passing down very structured information from generation to generation. They have complex music that’s adopted by other members of the population of that species, and it travels around the world like a kind of greatest-hits album.

(Read more about scientists’ stunning advances in understanding the culture of whales.)

There are Indigenous peoples all over Earth with incredibly rich and diverse connections to the water. How did these cultures inspire the Metkayina?

We did a lot of research about real Indigenous cultures that are very tightly associated with the ocean. We looked at Polynesian culture, which is a canoe trading culture. We decided not to do canoes other than some canoes that are used locally. The voyaging in our film—I can’t speak to future films—is not the [Polynesian] voyaging culture that uses the big canoes or waka as they call them here in New Zealand.

It was like, how do we take Indigenous culture here on our planet and put it through the lens of Pandora? There are [the Sama-Bajau], people in Indonesia who live on stilted homes and live on rafts. We looked at things like that.

How has your experience in ocean exploration and technology shaped your approach to filmmaking generally and The Way of Water specifically? 

There’s a lot of interconnections between my underwater exploration and filmmaking: Both involve small teams of people who are trying to do very difficult things in a coordinated fashion that requires a lot of planning. That I find very similar, especially when you’re creating new technology: to, let’s say, take a robotic vehicle inside the Titanic and survey it archaeologically or to build a new human-occupied vehicle to go to the deepest place on the planet. That’s small teams doing impossible-seeming things.

In making these Avatar movies, we’re way, way out in front at the bleeding edge of what is possible in terms of VFX [visual effects] and performance capture, so that’s an exciting challenge. I’m not asking the audience to think of this as some kind of tech demonstration; I want them to believe that we went to Pandora and shot it all as a big documentary. I don’t want them to think about how it was actually accomplished. So, the onus is on us, creatively, to try to make it seamless, to try to have everything that everybody does—every action, every riding of a creature and so on—be based in real-world physics. The physics of water on another planet are going to be the same as they are here. Water’s water.

We dedicated ourselves to this idea that we would take the actors into the water. We would teach them how to free-dive as part of their preparation for their characters, but also just practically so they could perform the scenes we teach them to scuba dive.

We built essentially mockups of the creatures that could do what the creatures [in The Way of Water] did: race around underwater at high speed, pop out of the water, fly over the surface of the water, go back into the water, and scream around underwater—and we figured out how you would really ride such a thing. It almost sounds impossible, right? Like a Harrier jet meets a submarine. We built it. I don’t know if you’ve ever seen it at resorts, these things where the guys go up 25 feet in the air. We use that jet-thruster technology to make essentially a Harrier jet that had a pilot inside it, and somebody could ride on top of it and could fly over the surface of the water, dive into the water, scream around, and then pop out of the water and do it all again. Dangerous as hell; we all enjoyed it for about a week down in the Bahamas.

But we figured out how you’d really ride such an animal and how you’d handle a spear or some other kind of weapon at the same time. We went out and gathered all that information, and got all that reference photography, brought it back into our filming environment, taught the actors how to do it, and put it all together. At the same time, we had to come up with all kinds of computational fluid dynamics simulations so that we could make it look real for their alien characters, because they’re not us physically.

You talk about the fidelity that you’re trying to achieve in these films, in making Pandora plausible and relatable. I think about the floating Hallelujah Mountains of the first film and how those were partially inspired by the Huangshan mountains of China. What real-world locations inspired what we’ll see in The Way of Water?

The most obvious connection between The Way of Water’s new habitats and what we have here on Earth are the tropical coral reefs and the tropical atoll formations, especially in the Central and Western Pacific: where you have these ranges of ancient volcanoes that are eroded down and form these atoll island chains. I’d spent a lot of time diving out in the Pacific amongst these atolls and at coral reefs all over the world.

All of our species of coral and large, soft, invertebrate animals, we put equivalents to those in our reef ecosystem in The Way of Water. It’s really a celebration of our reefs and atoll formations. It’s also a celebration of the Polynesian culture that spread in this vast diaspora through all these Pacific Islands. It’s a celebration of our ability as these highly adaptive creatures to go into different environments.

Ultimately, everything you see with the Na’vi is really the best of us, written large and blue and through the lens of science fiction. In a way, they’re aspirational characters. I live in an urban environment, I work 9-to-5, I have all these stressors, I have to pay my rent, my taxes—blah, blah, blah. I want to live like them. But how would one live like them?

Well, you’d have to have this deep, spiritual respect for the harmony and balance of nature. We don’t have that anymore, so we can’t get there from where we are. We have to learn it again. We have to learn what humanity once knew but has forgotten or suppressed.

To double back to a point you made earlier: The Way of Water is coming out at a time when the Earth’s oceans are in a damaged state, from climate change to overfishing, and there’s acute awareness of the environmental challenges we face. In this moment of all moments, how do you hope this movie lands with audiences?

The reason that I went down the path of making a series of films in the same universe is because I thought that what I needed to say artistically—to communicate with people—I could do within that framework. Obviously, shifting from the rainforest, which was the focus of the first film, to the ocean, [there] is, between the lines, a plea for the protection and conservation and celebration of our oceans. Hopefully we can turn back from a path that is putting the oceans under stress. I don’t even like to use the term “stress”: It’s used a lot in conservation, [but] if you consider fourth-stage cancer “stress,” yeah, it’s “stress.”

The coral reefs will be a thing that exists only in films in 50 to 75 years, in most places around the planet. That’s not okay. When I was a kid, I aspired to become a diver, so I could go and see this wonder and this beauty myself. And then I spent decades exploring and enjoying that world. My kids and my grandchildren won’t be able to do that. And so, it’s kind of a cri de cœur, if you want to put it that way: to remember, to celebrate and fall in love with again, and therefore remember to protect that which we’re losing.