They mostly get it wrong.



Film-makers have been infusing culture with their visions of aliens for more than a century, and almost all of them have been a lot like us. The Moon natives in the first cinematic trip into space, Georges Méliès’s La Voyage dans la Lune (1902), were Selenites, named after Selene, the Greek goddess of the Moon. They’re a bit like arthropods with bulbous heads and lobster claws, but mostly human – upright and bipedal. The next trip was when the 1919 adaptation of H. G. Wells’s The First Men in the Moon landed, which also had Selenites as the endogenous lunar men. Alas, all prints of the film are lost. In the few remaining stills from the shoot, the Selenites are also somewhat insectoid, but look disturbingly like the blue, globoid-headed, oval-bodied Igglepiggle from the bewildering otherworldly toddlers’ programme In the Night Garden.

And so the tone was set for a century of aliens – humanoid, insect or insect-like humans are the mainstay of cinematic extraterrestrials. We turn to human-like forms either because of budgetary constraints or for reasons of anthropocentrism.

We lazily assume aliens will be a bit like us, because we do like thinking about ourselves. Star Trek and dozens of imitators have got away with simply gluing bits of lump onto human faces or painting them green to indicate their non-human status. The Star Wars Universe offers little but variations on humans. Budget didn’t seem to be much of a problem in James Cameron’s Avatar (2009), just a tiresome lack of imagination. ‘Let’s make them taller than us, and a bit cat-like, but sexy, and give them tails. They need to be primitive but wise. Oh, and make them blue too.’

We have a pretty good grasp of evolution these days, and our bounteous fossil record, now coupled with genetics, gives us a picture of how life evolved on Earth. There are plenty of mysteries remaining, but we know much about our nearest ancestors: the emergence of bipedalism and all the many factors by which we came to be who we are. To assume that on other worlds, evolution would deliver a species identical in physical stature is plain silly.

We don’t really know why we became two-legged when almost all terrestrial animals are not, but we can hypothesise that it is an adaptation to a range of complex environmental conditions, primarily to equip a species for a life on the savanna rather than swinging in the trees, and an increased efficiency of movement.

If the Earth ever got a reboot, and the story ran again from the beginning, with just a few variables altered we would not have come out like this. Even a seemingly unconnected matter like the tilt of the Earth’s axis has played a crucial role. That 23° tilt, which gives us our seasons, was caused by a rock the size of Mars colliding with the neonate Earth, and knocking off a block that would form the Moon. Imagine if the rock had missed; no tilt, no seasons, no Moon, no tides. This would have meant a different weather system, different climate changes over time, and an entirely different set of evolutionary ancestors. Imagine if that six-mile-wide asteroid hadn’t tumbled out of the Cretaceous sky into what is now the Gulf of Mexico and caused an extinction level event that wiped out the dinosaurs and so many other species, yet allowed our small mammal ancestors to thrive. Imagine that rock being half the size, and only half of the dinosaurs had been wiped out. Would we be as we are? The answer is almost certainly no. Our form is not inevitable – it’s mere cosmic happenstance.

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Plan 9 From Outer Space (1959) © Distributors Corporation of America/Getty Images
Plan 9 From Outer Space (1959) © Distributors Corporation of America/Getty Images

Since the 1950s, aliens have frequently appeared as indistinguishable from humans on screen. Sometimes this is simply filmmaking on the cheap. Ed Wood’s Plan 9 From Outer Space (1959) is an equally derided and loved cult movie, sometimes cited as the worst ever made, with comically wobbly sets, flying saucers on strings, a clumsy and prolix script, and a cast of wrestlers, local celebrities and a female vampire impressionist. Human aliens arrive with their infamous ‘Plan 9’ to resurrect the Earth’s dead, notably in the form of Bela Lugosi (who, Fact Fans, died a few days into filming, and was replaced by Ed Wood’s chiropractor, who was much taller and bore no resemblance to Lugosi, but instead held a cape in front of his face; it wasn’t even the same cape though, as Lugosi was buried in the original).

Eight years earlier we met Klaatu, the humanoid in the classic The Day the Earth Stood Still (1951), with his atomic-age warning to Earth that we better shape up or be ‘reduced to a burned-out cinder’. There are also plenty of representations of an assumed evolved human alien, the so-called Greys, with spindly body, and big brainy heads and eyes, supposedly implying their superiority to us through cerebral evolution, and the move away from physical brute. Steven Spielberg seems to like them particularly. We see them in Close Encounters of the Third Kind (1977), back lit, gracile and graceful, and in fact played by young girls. E.T. (1982) was more green than grey (until he died), but those bodies return, even thinner and bulb-headed in AI: Artificial Intelligence (2001), though these turned out not to be aliens, but super-evolved robots.

We humans represent a very small proportion of life on Earth. Most organisms are single celled – bacteria or archaea, but I guess they’re too small to make cinematic creatures (though off-screen, even smaller replicating entities, viruses, do play the decisive role in our survival against the three-legged Martians from the War of the Worlds, 2005). Most animals on Earth are insects. We share ancestors with those creatures that crawleth about 550 million years ago, and though insects look very different from us mammals, the genes responsible for the formation of legs and eyes and the whole axis of their bodies are pretty much the same as in mammals, and their bodies are structured in the same way – a head with eyes and a mouth at one end, a tail at the other, legs in the middle. Nevertheless, since the Selenites, insects and other arthropods have served as inspiration for otherworldliness: Starship Troopers (1997), Independence Day (1996), Men in Black (1997), District 9 (2007), The Mist (2007), and dozens more.

In 1979, we were introduced to a new extraterrestrial insectoid in Alien, and then a whole swarm of them and their big-assed mother in 1986 in its sequel, Aliens. A 7 ft 2 Nigerian actor called Bolaji Badejo was inside that xenomorph suit in the first film, and there is a razor-tipped tail, and a lot of phallic imagery, but it is still a man in a suit – head and mouth(s) at the top; arms, fingers and legs all the way down. By Alien 3, the parasite has infected a dog, and the resulting mature animal is canine rather than humanoid. For all of the anthropomorphism of Alien and Aliens, and the caninomorphism of Alien 3, these creatures fit into a scientific idea that has been well considered. These titular xenomorphs are parasites, and their behaviour is perfectly believable in light of some of the breathtakingly grim parasitic behaviour we see in nature. If you don’t believe me, here are some examples.

The Alcon Blue butterfly (Phengaris alcon) is very pretty, but appearances can be deceiving for it is a rather wicked creature. It lays its eggs on the Swiss wild flower Gentiana, where the larva feed until they are fatted, and then loll on the ground waiting to be discovered by ants. The grubs secrete a chemical which mesmerises the poor deluded ants into thinking they are their own babies, and bring them into the hive, whereupon the butterfly grubs eat the ant grubs. Once ready to emerge into the world from its ant-cuckoo brood, the butterfly does have to run the gauntlet to escape, as the ants suddenly realise that this flap-winged thing is not actually one of them at all. However, the newborn butterfly is armoured with flaky scales that the ants struggle to grab hold of, and it bludgeons its way out, hotly pursued by some irate cuckolds.

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And if you think all this evolved opportunism is remarkable, consider the wasp Ichneumon eumerus: its main hosts are Alcon Blue grubs! The females scour the ground for the scent of the ant colonies, and will only enter those that have the butterfly larvae in them. Inside, she pierces the belly of the fattest butterfly grub using her very pointy ovipositor, and inserts a single egg. She also marks the nest with a chemical that warns off other ichneumon wasps from doing the same. After nine or ten months of being nurtured by ants inside a butterfly maggot pretending to be an ant, the wasp is ready to burst from its host, and releases a chemical that causes the ants to fight each other and not attack the wasp.

Parasitism like this is very alien to us humans, and yet it abounds in nature, and it’s pleasing to see elements of a parasitic life cycle present in the Alien films; the insertion of an egg into a host; the messy bursting forth; the armour plating; the shed skin. But imagine pitching the story of the Alcon Blue to a Hollywood producer. Nature is frequently hard to believe, and this butterfly story sounds just a little unlikely. Alongside the original Alien films (of which there were eventually four), there were two horrid spin-offs featuring another filmic alien, the Predator. The best thing about these wretched films was the tagline for the Alien versus Predator poster: ‘Whoever wins … we lose’. That’s how the ants must feel.

It is possible to get too lost and obsessed with the scientific verisimilitude in films. In general, I’m not that bothered if the science is not watertight, or set in galaxies far far from reality. One alien film, though, has caused me anger, hate and suffering – and, as all science fiction fans know, these emotions only lead to the dark side. Prometheus was so inconceivably awful in every aspect, and made so little sense in terms of basic plotting, that it seems fair game to pile criticism onto the woefully ill-conceived science, which as presumably intended to underwrite the plot, but in fact undermined it.

It begins with an extremely tall and preposterously muscled human-like alabaster-skinned man wearing a nappy on a clifftop, possibly in Iceland. There, for reasons unclear at the time, and never explained, he consumes a small vial of black stuff, grimaces, and then crumbles fragmented into the water below. The camera zooms into the molecules of his disintegrated life. As the title card shamelessly mocked the iconic lettering of the first Alien film, DNA from the giant muscular fellow swirled in the waters of this primordial incubator. But it was a double helix that twisted to the left, and thus Prometheus was wrong from the very first frame. All DNA on Earth turns to the right, like a corkscrew, a fact that betrays its singular origin and the shared ancestry of all life on this planet. This mistake happens a lot, and is sort of forgivable if I’m in a good mood. But it’s just wrong.

Anyway, with this set up, the idea is that we were engineered by a species that came before all life on Earth and gave up its DNA (regardless of its handedness) to seed evolution. It’s a version of a theory called panspermia, much loved by science fiction authors, where aliens plant life on other planets, either through intent or just accidental cosmic pollution. It’s a nice idea, but in my view firmly in the realm of science fiction as we have good models for how life began on Earth, and none of them requires either alien or divine intervention.

According to the plot in Prometheus, these ancient anthropomorphised aliens gave the planet DNA, which over the course of life on Earth ended up with us looking like shorter, darker and altogether less beach-bodied versions of our ancestors. If that were the case, then why did evolution take such a circuitous route to get back to the creator’s form? Why did we spend so much time hairy and on all fours? Or as brutish reptiles? Or indeed, why did our ancestors spend so much time – probably 2 billion years – as single-celled organisms, if we were only waiting to become lesser versions of what our creators already were?

This panspermia fallacy is not the only alien encounter in Prometheus; there’s a much more phallic one too. One of the mission scientists discovers a wormy alien species. This, we assume, is the first contact that any human has made with an extraterrestrial, and because he’s probably the worst scientist in the history of science, he immediately takes his helmet off. He then does a sort of ‘coochy coochy coo’, as the worm rears up to reveal not just phallic imagery but a fanged vagina as a mouth. It then chews his face off, which comes as some relief to the audience (though it should be noted that such is the baffling narrative and scientific confusion in this film, this doesn’t kill him; he comes back later as a giant, angry, blister-headed zombie – perhaps this is how anyone would react to having one’s face devoured by an acid spitting vagina dentata).

I digress. Prometheus is a terrible film because of its nonsensical script, not because of its lazy science and unimaginative aliens. It is impossible to get aliens right on screen, because we have a sample size of life in the Universe of just one. For all the astonishing variety of life on Earth, it is all part of the same tree. We have the same DNA (which is always a right-handed twist), the same cell structures, the same basis for harvesting energy from the environment.

I consider that there are two ways of creating successful aliens on screen. The first is not to try at all. Disguise is a perpetual theme of humanoid aliens. They walk among us, hiding either to enact their nefarious plans (Invasion of the Body Snatchers, 1956, 1978; They Live, 1988; Under the Skin, 2013), to fit in (Superman in many movies; Starman, 1984), or simply to survive (The Thing, 1981; The Man Who Fell to Earth, 1976, though it has never been made explicitly clear that the actor who played the title role in the latter film, David Bowie, was terrestrial in origin. Wherever he is now, it’s not Earth.)

The other method of dealing with an authentic alien is simply to be incomprehensible. Stanislaw Lem wrote the science fiction novel Solaris with this in mind. “[I] wanted to create a vision of a human encounter with something that certainly exists, in a mighty manner perhaps, but cannot be reduced to human concepts, ideas or images.”

It was filmed three times, in 1968, 1972 and 2002. The two most recent are both stunning in different ways, both considered meditations on death and consciousness. The non-human life is the planet Solaris, as far as we can understand it, around which a space station orbits, with a crew in place to study it. The alien presence manifests itself as memories of people. Dead relatives or wives are conjured from the minds of the crew, incomplete or misremembered, and always upsetting, yet addictive to the extent that the crew don’t want to return to Earth, even as their ship’s orbit decays into the planet. No attempt is made in either film to explain the alien intelligence; it is merely an expression of consciousness utterly different from our own.

Kubrick’s science fiction masterpiece, 2001: A Space Odyssey (1968), uses a similar idea, with the presence of the black monoliths, one triggering the advent of weaponised tool use in our ape ancestors, and another 3 million years later propelling us forward in an unexplained evolutionary leap. In doing so, he upturns Darwinian natural selection in a way that does not upset me, an evolutionary biologist. What is the alien? We don’t know. But it is not us, nor anything we recognise.

Jodie Foster as the astronomer Dr Ellie Arroway in Contact (1997) © Francois Duhamel/Sygma © Getty Images
Jodie Foster as the astronomer Dr Ellie Arroway in Contact (1997) © Francois Duhamel/Sygma © Getty Images

Carl Sagan’s novel Contact was made into a movie of the same name in 1997 starring Jodie Foster as the astronomer Dr Ellie Arroway, possibly the best on-screen scientist in cinema’s history. She detects a repeating signal from a nearby star system that cannot be anything other than the product of extraterrestrial intelligence. Within the signal there is a set of instructions on how to meet the entities at the other end. This is perfect science fiction, in that it is fiction rooted in science. It is a fantasy set-up and it relies on non-existent technology and phenomena (such as the Hollywood staple for travelling interstellar distances, the wormhole, which are at best theoretical). But they are in the service of a fantastic and skilfully told thriller about how science works and how and why we explore. The alien tech works. When Dr Arroway awakes to find herself in a distant star system, she’s on a tropical beach. The sky is different, the wormhole swirls above her, and it all shimmers in an unearthly way. A blurry spectre approaches, and as it comes into focus, it is not alien at all. It is her father, who had died when she was 10. Some people groan at this, writing it off as base sentimentality.

I find it powerfully moving, not least because she figures it out in seconds.

‘None of this is real … While I was unconscious you downloaded my thoughts, my memories even?’

‘There’s my scientist,’ the alien replies. ‘We thought this might make it easier for you’.

Carl Sagan figured it out too. We can’t conceive of alien life. If it does exist, it’s difficult to imagine it not being Darwinian in its nature, and similarly it’s hard to imagine that it wouldn’t work in a similar way to life on Earth, that is, powered by a mechanism for continuously extracting energy from its surroundings, and slowing down the inevitable increase in entropy as long as it lives. But we cannot imagine the evolutionary pressures that an alien would have endured over billions of years to shape its physical form, or its behaviour. If there is intelligent life in the Universe, we will have to wait a long time before we meet it.

In the mean time, we search. Are we alone? Other contributors in this collection will have given reasoned or mathematical answers. For me, the real answer is that the more we look, the more we find out about ourselves, both in science and in science fiction. As Contact’s alien concludes (though I can quite imagine Carl Sagan saying it himself): In all our searching, the only thing we’ve found that makes the emptiness bearable is each other.

This excerpt is from ALIENS, Science Asks: Is Anyone Out There?, a collection of essays about alien life from scientists such as Martin Rees, Dallas Campbell and Seth Shostak, edited by Professor Jim Al-Khalili. The book is out now (Profile books. £7.99)
This excerpt is from ALIENS, Science Asks: Is Anyone Out There?, a collection of essays about alien life from scientists such as Martin Rees, Dallas Campbell and Seth Shostak, edited by Professor Jim Al-Khalili. The book is out now (Profile books. £7.99)


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