How close to reality are the androids in Alien and Prometheus?

When Alien came out in 1979, roboticists were making wheeled boxes that crashed into walls. Ash - the film's traitorous android - was pure fantasy. But when Prometheus comes out this summer, Weyland Industries' David 8 enters a world with plenty of real-life androids.

Given what we've learned about androids in the past few decades, which tropes about artificial humans is it time to throw in the dustbin?

To be sure, today's real-life androids, such as Hiroshi Ishiguro's Geminoid series and the "character robots" made by Hanson Robotics, are a long way from living among us undetected. Conceptually, however, these machines already surpass the awkward mannequins, abrupt killers, and high-tech Pinocchios we see so often in fiction.

Let's take a look at six android cliches, as viewed through the prism of real-world technologies. Which tropes will endure? Which ones deserve to be retired like a replicant?

The android that acts like a machine

The only reason fictional androids quizzically cock their heads, cool their voices and generally robot around is because they're played by human actors. Something, after all, has to signal their mechanistic nature. Real-life roboticists, however, understand the importance of being naturalistic. Hanson Robotics' Jules is not only physically expressive, but also speaks with emotional intelligence and depth of feeling. The chest of Henrik Scharfe's Geminoid doppleganger heaves slightly, as if the machine were breathing. Nonverbal cues can be just as reassuring as kind words.

The real barrier may not be technical, but cultural. In Alone Together, former roboticist and technology critic Sherry Turkle tells the story of the theme park that replaced biological animals with animatronics. Customers wanted animals that behaved how they imagined them behaving, not how the animals actually behaved, which mostly involved lying around. The hipster of the future may consciously choose an android with a jerky style because of its retro appeal. The android's mechanality, in other words, becomes a matter of taste, a social marker with all the attendant envies and resentments.

The android that finds humanity to be a deep, abiding mystery

We flatter ourselves: A machine could never understand jokes. Then IBM's Watson uses natural language processing to understand the punning intent behind Jeopardy! questions, and we're proven wrong. If anything, the android will see us more clearly than we see ourselves. Jeremy Bailenson, director of Stanford's Virtual Human Interaction Lab, used the Xbox Kinect to analyze body language during student-teacher interactions to "mathematically uncover subtle movement patterns, many of which would not be noticed by the human eye." Psychologist Paul Ekman has discovered the "micro-expressions" the human face flashes during a lie-if facial recognition software can read it, then the android can know it.

Ultimately, as "big data" gets bigger we'll ask ourselves what we want our androids to share. Do we charge them with stopping us from making bad life decisions? Or do they help us maintain our innocence? Fiction has its Rikers, the wise humans who preside over the sentient machine, often with a whiff of bearded condescension. Maybe the android will be the one who wears the bemused smile.

The android that has a predictable job

Pity the android career counselor, forced to suggest either science officer, soldier, or prostitute. True, the latest DARPA Grand Challenge is for a humanoid robot and the Realdoll has us on the path to David Levy's vision in Love + Sex with Robots. But the android's emotionality and interpersonal skills will give it opportunities beyond proxy warfare or sexual surrogacy. The Japanese government is subsidizing the development of robot caregivers to meet the needs of its aging population. No matter how sick the patient is, Paro the therapeutic seal never gets tired or frustrated or feels compelled to write a memoir about its experience.

The android may end up on the battlefield or in the brothel, but the wind-up girls (and boys) are more likely to be the patient, cheerful helpers in the therapist's office, the retirement home, the classroom. The challenge for humans will be dealing with the personal and social consequences of offloading our familial and civic duties. The robot takes your job. The android steals your role. Welcome to Mommy Wars: 2056.

The android that suddenly turns murderous

Thanks to the libertarian values of today's tech culture it's easy to imagine the freewheeling - even dangerous -android. But The Master Switch, by Columbia law professor and net neutrality guru Tim Wu, reminds us that technology goes through cycles of freedom and regulation. (During AT&T's government-sanctioned monopoly, for example, it was illegal to tamper with your phone jack.) The viral video for David 8 has an amusing line about his ability to act outside ethical boundaries, but the widespread adoption of androids will hinge, boringly, on safety.

In their paper "Do People Hold a Robot Morally Accountable for the Harm it Causes?" University of Washington psychologists found that the answer was (mostly) yes. Even powerful, post-apocalyptic corporations will be limited by fear of boycott, lawsuit, and recall. In fact, given the trend in caregiving robotics, this technology will help us follow our diet, make sure we recycle, and remind us to accentuate the positive. You'll see an android at a cocktail party and beat your escape, not for fear of it gouging out your eyes with its thumbs, but of it killing your buzz.

The android that doesn't know it's not human

In The Shallows, journalist Nicholas Carr says that technology generally does one of four things: enhance our strength, sharpen our senses, change our environment, or extend or support our mental powers. The android that doesn't know itself makes for a great story, but where's the advantage? Indeed, the android that honestly believes it's softer, weaker and more vulnerable than it is would pose a significant risk to the meatbags in its tender care.

If anything, the android's smarts, emotionality and sense of purpose would more likely lead to a strong sense of identity. In Aliens, when Bishop is referred to as "synthetic" he says prefers the term "artificial person." In 1986, this was a jab at political correctness. Today, this sounds like a perfectly reasonable request (or perhaps the kind of deflective joke Siri might make). The android self will test us not with its limitations, but with its competence. Will we be able to resist dragging them down to our level?

The android that yearns to be human

In his essay What Is It Like to Be a Bat? philosopher Thomas Nagel argues the impossibility of imagining the subjective experience of another creature. Anthropomorphism and anthropocentrism are inescapable structures of the mind. We imagine the fake human wants to be real because . . . well, what else would it want to be?

In real life a strong, autonomous, conscious technology that also has a gnawing, existential hunger to be something it can never be is a product that never makes it out of the brainstorming session. Picture instead the Apple of androids: intuitive, understanding, confident, cool. As they tuck us in at night they'll say they wish they were human and entertain our every fantasy of a pre-post-human world. But this will only be part of their irresistible charm. No, my friend. They won't want to be like us. Not one bit. But you can bet we'll want to be like them.

Dennis Cass is a former journalist who's reinventing himself as a science fiction author. He's currently working on a book that will help average, everyday people with their android problems. Follow him on Twitter @denniscass.