The difficult thing about creating a fictional alien species is that if they are too familiar, they seem inauthentic. Slap some bumps on the forehead and voilà : every Star Trek alien ever. And, the Star Trek franchise eventually had to explain this phenotypical homogeneity (ask a fan, but it’s in a Next Generation episode) to keep the credibility of the milieu intact.

On the other hand, to seem scientifically authentic aliens have to be … unfamiliar? Unrelatable? What’s a better word?

Alien.

However, if you take the creative process step-by-step, you can work outward from simple premises to alien species that are both inhuman yet believable and understandable.

Step 1
Think evolution.

It’s really easy to imagine natural selection: just put yourself in a hypothetical environment and focus on what would feel most threatening to your ability to survive. Survive and produce offspring.

Imagine a world with a thick layer of intertwined vegetation, trees connected in a dense lattice-work, like living inside a huge sponge.   What would it feel like being inside such a three-dimensional jungle?  How would the danger of being naturally deselected manifest itself?

What comes to my mind first is how worried I would be that something predatory would be sneaking up behind me.  This fear is bad enough in one of Earth’s forests, which are nowhere near as claustrophobic as the alien forest we’re concocting here.

It reminds me of something an Iráq veteran once told me about clearing a large building with doors and stairwells (and thus danger) in every direction: “You just wish you had eyes on the back of your head.”

So, how about that? An alien species with eyes on the back of its head, 360° sight.

Then, you add finishing touches. The inherent darkness in such an environment (coupled with the reflective and filtering effects of different species of foliage) would require sensitivity to a wider range of light frequencies.

It’s also likely that such an alien species would see better than we can except in one aspect: unlike a creature that evolved on the savannah, they would have no need for long distance vision.

So, we’re off to a good start!

Step 2
Now, think social evolution

How would the culture of creatures with all-around vision differ from ours? If you’ll pardon the etymological pun, let’s speculate…

They draw diagrams and charts as we do, but their representational art consists entirely of object drawings and portraits with no background. Why? Screen images of scenery, even landscape paintings, make them a bit uneasy because what they see in front of them doesn’t jibe with what they see behind them.

Let’s say they’ve been observed actually closing their back eyes when looking at our television images and paintings, as if trying to imagine the other side of the world they’re seeing with their front eyes, or simply to block out the conflicting input.

They are good with sculpture, and much better at thinking in three dimensions, which would make them better space navigators than humans. Are their navigational charts immersive holograms, so they can sit among the stars the way their ancestors sat among the trees?

Step 3
Don’t invent a one-trick pony

How can you throw a spin on this alien race that makes it more interesting?

Maybe, despite their excellent eye for detail, their social instincts are tied more to scent than sight. After all, scent travels around corners, so knowing friend and foe in a three-dimensional forest might reasonably take an olfactory turn.

Rather than taking photos of loved ones with them, do they take swatches of cloth that were pressed against the skin until they picked up the person’s scent? This would certainly be an interesting detail for a first encounter story, as humans gradually figure out what these odd bits of fabric represent.

Step 4
Flip the script.

It is also important to remember that “alien” is a subjective concept. Consider our alien-ness to them.  What do humans remind them of?

Does our natural human scent remind them of something unpleasant?  How would this affect inter-species relationships and diplomacy?  Or, even more intriguing, what if we remind them of something pleasant, like their planet’s flowers? Or food.

What do they think of our use of rear-view mirrors?  Is this funny or disturbing to them?

Do they laugh when we try to use their immersive star charts, spinning around to orient ourselves to the confusing 3D environment?

Do they find our use of augmenting scents and perfumes confusing and dishonest? Or intriguing and poetic?

Wrapping it Up

The final touch is knowing when to stop. Realistically, almost everything about an alien species will be worthy of comment, but writing fictional aliens requires following the dictates of fiction as well as scientific realism.

A good rule of thumb when describing characters is to give the reader three or four descriptors and then stop. The same rule works well with aliens. More details can be added as the story develops, but you don’t want to weigh the story down with a full investigation of every aspect of alien biology and society.

Also, it’s a good idea to give the aliens an exonym, a name given to them by humans. It’s a sci-fi cliché that alien languages are difficult to transliterate into human speech, but that is a realistic assumption.

Transliteration between human languages, where the organs of speech are identical from population to population, is notoriously problematic. Multiply that by whatever factor is reasonable for a creature from a completely different evolutionary history.

As a thought experiment, imagine trying to spell dolphin speech with the Latin alphabet. Ridiculous.

So feel free to dodge the conceit of giving your aliens an alien-sounding name. Even the “official” name for an alien species would likely be a human term, so the most realistic way to go is not to make the aliens’ name an alien name.

Now… crack open that word processor and get to writing!