The Science of Avatar

by Stephen Baxter

  However, the biologists don’t understand quite why we lost our tails. It presumably has something to do with the way we and our cousins have learned to walk on two feet. Monkeys which are very active in tall trees, running along the branches, jumping and swinging, use their tails a lot, including for balance. But creatures that move slowly in the lower branches, like sloths and koalas, are tailless. In Borneo the long-tailed macaque lives high in the trees—and has a long tail, as the name indicates—while its close cousin the pig-tailed macaque lives on the ground, and has a short tail.

  With apes, the picture is more complex, and perhaps has something to do with walking on two legs. Chimps after all do climb trees, and so do gibbons, and neither has a tail. But these creatures are often seen to walk bipedally, and perhaps that has led to natural selection against tails. With us the selection pressure must have been more extreme. After our ancestors split from the chimpanzees they became creatures like upright chimps, australopithecines, clinging to the forest edge yet foraging out onto the savannah, gradually becoming more and more committed to bipedalism. Goodbye tail.

  As for the Na’vi, their evolutionary trajectory has clearly been different. They have stayed closer to their forest. Compared to us they are terrifically adept in the trees, good at running along narrow branches, at swinging like Tarzan, at leaping huge distances. No wonder they have retained their tails.

  Other Na’vi tree-climbing adaptations might include their bone structure, which is strengthened by a natural carbon fibre, an advantage shared by many Pandoran creatures such as the banshee. And perhaps they have better proprioception than we do. Proprioception is the sense of the position of the parts of the body—of place, movement, locomotion. Maybe that’s why the Na’vi, on the backs of their banshees, are such good natural pilots.

  We glimpse the Na’vi’s closeness to their trees in one other touching detail. During his first night in Hometree, avatar-Jake sleeps with the Na’vi, curled up in a leaf-hammock high in the branches. In the background we see a family group tucked up in a single leaf-hammock. The leaf-hammock is a plant, an epiphyte, a plant not rooted in the ground but using the tree for support, while extracting nutrients from rainwater and other sources. The Na’vi call the hammock “safe in the arms of Eywa”—Eywa k’sey nivi’bri’sta. Similarly the chimps like to sleep in nests of leaves high above the ground. And, I like to think, maybe our australopithecine ancestors returned to sleep in the green comfort of the high branches, after a day in the brutal openness of the savannah.

  Why should the Na’vi be so disconcertingly humanoid, and so different from the background of their own world?

  Of course, looking from the outside at the Avatar universe, we can always point to creative licence. Neytiri, with her catlike features, is sufficiently human to be a sympathetic character, but with a mix of familiar-but-incongruous features to give the audience the sense of the alien. Neytiri trying to hug Jake with four arms might have looked distractingly comical!

  But within the Avatar universe observers are puzzled too.

  Among the hypotheses to explain the Na’vi’s human-ness are convergent evolution, as we discussed in Chapter 23; perhaps the four-limbed humanoid form is an inevitable end-point of evolution on any world. Or perhaps Na’vi and humans are actually related, through some process of interstellar panspermia, either natural or purposeful. Or, some suspect, maybe a divine hand has been at work; perhaps both we and the Na’vi are the result of a process of intelligent design—but the whole subject of the theological status of the Na’vi is fraught. As yet there is no clear answer. Maybe one of these ideas is right; maybe none is. We have much to learn about the Na’vi, and their world.

  However humanoid they are, with their language, art, music, hunting prowess and artefacts, the Na’vi are clearly as intelligent as we are—if not more so, despite our more advanced technologies. And as such encountering them is a fulfilment of a very ancient dream: of finding other minds in the universe.

  26

  OTHER MINDS

  The idea of extraterrestrial intelligence has very deep roots in our culture.

  Renaissance thinkers were astounded by Galileo’s first telescopic observation of the moons of Jupiter, a system invisible to the naked eye, yet like a miniature solar system in its own right. As the astronomer Kepler said, “Those four little moons exist for Jupiter, not for us… We deduce with the highest degree of probability that Jupiter is inhabited.”

  This powerful intuition of the commonness of life has always caused great controversy, just as it does today. Saint Augustine, for example, long ago decided that aliens couldn’t exist. If they did, they would require salvation—a Christ of their own—but that would contradict the uniqueness of Christ, which is theologically unacceptable.

  On the other hand there are some who believe that alien visitors have visited the Earth, and may indeed be among us now. Personally I am sceptical about the UFO narrative. I’ve no doubt that many reported sightings are based on something real and observable—odd atmospheric phenomena, sightings of secretive military projects—but I’ve seen or heard of no firm evidence of any extraterrestrial intelligence behind any reported sighting. And it’s just too hard for me to believe that creatures advanced enough to cross the stars would behave in the secretive, vindictive and downright irrational manner many reports claim…

  And yet.

  If we aren’t programmed by evolution to register something, maybe we simply don’t see it. There is an apocryphal story that Captain Cook encountered islanders who seemed unable to see his great ships, until the crew launched their smaller, more familiar-looking boats to row to shore. The islanders had never seen such huge structures before, and they simply did not have the conceptual equipment to take them in. Similarly, an alien artefact would be in a different category of object to anything previously encountered by a human being, neither of the natural world, nor created by a human. And if a UFO were to visit the Earth, then perhaps elusive, half-seen glimpses, wrongly interpreted in terms of familiar objects, is precisely the kind of “evidence” we should expect.

  But don’t quote me on that.

  Today, fully trained scientists armed with the most modern equipment are busily searching for evidence of alien minds.

  2010 saw the fiftieth anniversary of Project Ozma, the first modern experiment in SETI (Search for Extraterrestrial Intelligence), when, back in 1960, American radio astronomer Frank Drake listened for alien signals from two stars at one frequency for a week. The idea came from a seminal paper published in Nature in 1959 by two physicists, Giuseppe Cocconi and Philip Morrison, who realised that the then relatively new radio telescopes could be used to send signals between the stars: “Few will deny the profound importance, practical and philosophical, which the detection of interstellar communications would have.” In the last few years I’ve become involved with SETI myself, having joined one of the SETI academic task forces, responsible for trying to imagine the consequences of a detection.

  But Frank Drake heard nothing in 1960. And after fifty years, surely the most striking thing about modern SETI is that there have been no positive detections. What’s going on?

  Advocates of radio-astronomy SETI point out how limited the searches have been so far; only a small number of stars in a small range of frequency domains for limited times have actually been studied. But there have also been unsuccessful searches for other sorts of evidence, such as artefacts at gravitationally stable points in the solar system. Even distant galaxies have been examined, fruitlessly, for signs of cultivation by super-intelligences, as in the Carl Sagan novel Contact and the Robert Zemeckis movie based on it.

  Absence of evidence is not evidence of absence; we can’t yet conclude we are alone. Nevertheless it can’t be denied that the sky is not full of radio-noisy, close-by civilisations, as might have been hoped back in 1960.

  A paradox is emerging. In Chapter 22 we looked at the origin of life, and ways life could spread naturally from world to wo
rld. Life emerged on Earth about as quickly as it could. If it did so here, why not elsewhere? What’s more, our experience of Earth shows us that if life exists, it spreads wherever it can. The Galaxy is big, but old enough for life to have spread across it many times over, even if it travelled at speeds much less than that of light. So where is everybody? This is a development of a back-of-the-envelope argument first made in the 1950s by the great physicist Enrico Fermi (supposedly in the course of a long lunch). It has become known as the Fermi Paradox: if they exist, we should see them.

  Possible resolutions of the Paradox have been extensively explored in science fiction, and in science. Perhaps there is some higher form of existence, as unimaginable to us as a Beethoven symphony is unimaginable to a single neuron in its composer’s brain. Or it may be that there are many species—like the dolphins, perhaps—with intelligence but without the opportunity to develop technology, because they live in an aqueous environment, or are spun out among the great rich interstellar clouds. Or maybe they simply aren’t interested. Frank Drake’s radio telescopes would not detect a trace of the Na’vi, inhabitants of the nearest star system, because they have better things to do than build radio transmitters. Or maybe most advanced technological species blow themselves up, as we’ve come close to doing, or exhaust the resources of their world, as in the “ecocide” of the Avatar future.

  But to resolve Fermi you have to believe that everybody is the same; all it would take is one exception, one brash, noisy, expansionist, technological species like ourselves to survive the bottleneck of ecocide and war, anywhere nearby, and we would notice them.

  Another class of possibilities is that they are indeed here—but they choose not to be seen by us. This kind of notion is generally known as a “zoo hypothesis.” The UFO mythos is an example of this. In Star Trek, the Prime Directive dictates that junior species should be left alone and given room to grow until they have reached star flight capability. Perhaps they really are here, all around us, concealed in some kind of high-tech duck blinds—hiding from us for good intentions, or bad.

  A final possible way to resolve Fermi strikes me as the worst of all. What if there are no Na’vi? What if, despite our intuition to the contrary, we are, after all, truly alone? What if our tiny Earth really is the only harbour of advanced life and mind in the cosmos? We saw in Chapter 23 that multicellular life arose quite late in the story of life on Earth. Intelligent life of our technological kind only arose in the last hundred thousand years or so, a tiny fraction (one forty-thousandth) of life’s duration on Earth. So maybe it only happened just the once, right here.

  In which case, surely our first duty is not to wipe ourselves out. For if we allow ourselves to become extinct, the universe will continue to unfold according to the mindless logic of physical law, but there will be nobody even to mourn our passing.

  You might ask why we so long to discover the alien. Why do we find the idea of meeting the Na’vi so attractive? And why do we long to talk to them?

  I have a personal theory that it’s because we aren’t used to being alone. It’s unusual on Earth for there only to be one species of a class of advanced mammal, as humans are unique. There are many species of monkeys, of whales, even of elephants and chimps. The dolphins have complicated social lives that routinely involve interactions between species.

  But we have increasing evidence that in the past we did share the world with many other sorts of hominid. The Neanderthals who died out some thirty thousand years ago were probably our closest cousins, but now there is new and exciting evidence of other sorts of humans surviving until quite recently. The diminutive “hobbits” of Indonesia may have lasted until a mere thirteen thousand years ago, and in March 2010 German scientists discovered a bit of bone from a child’s finger, in a cave in Siberia, that came from yet another hominid species that was still around some thirty thousand years ago. So as recently as that we shared the world with at least three cousins, three other twigs from the bushy human family tree, and I wouldn’t be surprised if the future brings more discoveries of this type.

  We evolved in a world full of other human types—not just strangers, but creatures of another sort, with minds somewhere between ours and the chimps’. And now that they’re all gone, we know something is missing from the world, even if we don’t know what it is. Maybe we dream of the Na’vi on their world because they remind us of the vanished cousins on our own.

  In the universe of Avatar some, at least, of these questions have been answered. But the discovery of the Na’vi on Pandora was a big surprise in many ways.

  Humanity is a young species in a very old universe; it was expected that any intelligences out there, if they exist at all, were probably much older than mankind—and perhaps that very advancement was why we couldn’t perceive them. So nobody expected to find stone age humanoids inhabiting a jungle world orbiting the nearest star. But then, nobody expected to find Jupiter-sized worlds orbiting closer to their stars than Mercury does to the sun. The universe is full of surprises; in a way that’s the point of doing science.

  But if we do find the alien, will this dream of the future turn into a nightmare of the past?

  27

  FIRST CONTACT

  Jake Sully’s first meeting with Neytiri is not humanity’s first contact with the Na’vi. That came about when the first unmanned probes landed on Pandora, and blue-tinged faces peered curiously into the camera lenses.

  But by then the value of unobtanium had already been realised; RDA was already in operation. And RDA was not best pleased. Loud protests were made that the natives must be protected. Cynics assumed that RDA, more or less beyond the control of Earth, would see the Na’vi as nothing but an obstacle in the way of it achieving its own goals.

  Meanwhile the first samples from Pandora were returned to Earth: minerals like unobtanium—and living things, plants, animals, heavily quarantined and controlled, specimens of the flora and fauna for scientific studies and zoos, commercially valuable properties such as the basis of novel drugs.

  Wherever we’ve travelled we’ve always brought with us a host of fellow travellers from viruses to rats, “invasive” species that have often done a great deal of damage to native biospheres. Pandora’s environment is not identical to Earth’s, and it’s not clear how easy it would be for terrestrial life to gain a foothold there. But I’m willing to bet that some of our hardiest “extremophile” bugs at least, that can withstand extremes of heat and cold, wet and dry, even radiation baths and oxygen deprivation, could survive there. And what if Pandoran life forms got loose on Earth? Maybe the hardier bugs of Pandora, bred on a tougher world, would prosper here, having evaded all attempts at quarantine and escaped, as living things tend to find a way to do.

  And what of the Na’vi? Their genetic material must have been transported to Earth for analysis to support the avatar project. Cadavers were needed for dissection. And perhaps some Na’vi were brought back live.

  Imagine the sensation a live Na’vi would have made! These tall, skinny, blue-tinted creatures, as ungainly as giraffes in Earth’s heavy gravity, wearing their own exopacks to enable them to breathe our air… The first Indians brought back to Europe by the conquistadors were a similar wonder. Scientists, historians, anthropologists, linguists and other specialists would have pounced on them. Maybe Na’vi ethnic “fashions” were all the rage for a while.

  What might have become of that handful of Na’vi, transported across the light years? Perhaps they would have been taught English, and dressed up in suits and ties to be presented to presidents and monarchs. Or perhaps they would have been cooped up in zoo “habitats” with Pandora-like conditions, while their children were taken off to be experimented on, their genetics pulled apart, their bodies mined for such treasures as their carbon-fibre-reinforced bones. Either way they would have been cut off, not just from their people, their culture, but from Eywa—and from the possibility of joining their ancestors after death (see Chapter 29). And after he died the skelet
on of the first Na’vi brought to Earth, no doubt given some human name like “Blue George,” would have been set up on a stand in a natural history museum.

  Meanwhile, far away, on Pandora, the conflict we see in Avatar would have begun, and the Na’vi would have started to die at human hands.

  Does it have to be that way?

  And what if we were on the receiving end?

  Certainly, if you’re a fan of peace, love and understanding, the precedent of first contact among human cultures is not encouraging.

  In 1492 Christopher Columbus “discovered” a new world, and a whole branch of mankind nobody in Europe had any idea existed before. Just like Avatar’s RDA seeking unobtanium, the monarchs who sponsored the early explorers wanted New World gold and other goods to fund their own projects, notably wars with their Christian rivals and Muslim enemies. Columbus himself was a militant Christian who dreamed of finding a new ocean trade route to Asia, and of joining forces with the Mongol emperors to attack Islam from the east. None of this had anything to do with the Native Americans, but the Europeans had the technology to impose their own agenda on the peoples they found.

  Perhaps the most single dramatic moment in the astonishing saga of contact and conquest that followed was the encounter in the Peruvian highlands between the Inca emperor Atahuallpa and the Spanish conquistador Francisco Pizarro, in November 1532, just forty years after Columbus. Atahuallpa ruled the most populous and advanced state in the New World; he had millions of subjects and an army tens of thousands strong. Pizarro led less than two hundred Spaniards. Within minutes of their encounter, Pizarro had captured Atahuallpa. And in a subsequent battle, the Spaniards, with no losses, defeated a native army hundreds of times more numerous, killing thousands. In mere decades the Inca empire had collapsed.