Forget about going to the movies to understand what a real alien might look like, as the Hollywood kind are generally just men in play-suits or a bit of computer-generated special effects. If you want to see something really “alien” go for a walk in a forest, down by a lake, or along the sea shore, and look at the astounding diversity of life here on Earth. Much of it defies the imagination of the best science fiction writers.
As a science fiction writer, I enjoy thinking conceptually about the various forms in which alien life may exist. It’s not a case of trying to come up with creatures that have an absurd number of arms or a something weird and implausible, like a star-whale, rather it’s an attempt to consider how life could evolve in different environs and to consider how we might interact with any alien intelligence.
And it’s not all death rays and anal probes, there has to be rational, reasonable, plausible motivations behind the actions of any intelligent being, human or alien. If an alien space craft ever does arrive on our front door step, the single most likely reason for it to turn up would be exploration, not exploitation.
The most precious commodity in the universe is life itself. Any visiting aliens are going to want to understand how our evolutionary past led to our current biodiversity, so rather than finding them hovering over the White House with a laser beam poised to fire, you’re more likely to find them in universities and museums, perhaps even helping out on a dinosaur dig.
One thing that’s missing from almost all alien movies is an ecosystem. Aliens, as Hollywood portrays them, are only ever shown as a single species. For all its faults, the movie Prometheus is one of the few movies that had several variants of alien life, one of which eventually transforms into something vaguely like the critters Ripley runs into. In reality, though, aliens will evolve in an ecosystem that’s at least as complex and diverse as our own, with as many of the subtleties and surprises as we find on Earth. In this regard, the best way to understand alien life before we come across any actual examples is to better understand our own biosphere.
Although we have no idea what aliens look like, we can be reasonably certain they won’t look anything like us. Good science fiction writers try to escape the regular, predictable alien-tropes, where aliens are bipeds roughly the size of a man or slightly larger and more imposing, having arms and legs along with a clearly recognizable head with two eyes and a mouth, etc. There certainly could be some convergent evolution in our celestial neighbours, but given the extreme diversity of life on Earth, any similarities are probably going to be quite fleeting. Life on Earth demonstrates that an astounding array of differences are possible.
What could be more “alien” to us than an octopus, or the zombie-like sea squirt that eats its own brains? And an octopus is more than just some squidgy alien-esque invertebrate with eight flexible arms, those arms think for themselves, being semi-autonomous, with their own ganglia. Essentially, an octopus is a living neural network with a central brain that issues orders to the arms and then leaves them to get the job done while it moves on to think about something else. Quite a marvellous adaptation, and this highlights something missing from movies. In movies, aliens are visibly distinct and different to humans, even if it’s only by a set of pointy ears. In reality, the physiology of aliens is going to be vastly different to that of Homo sapiens, from the microscopic layer on up through to morphology. They may well have “brains” that are sooo distributed that there’s no one central point at all, extending the kind of adaptation we see in the octopus even further.
It’s all speculation, of course, but speculation based on the rudiments of life we see around us and not just on our imagination.
Octopus and cuttlefish are remarkably intelligent, being capable of negotiating a maze, solving puzzles and opening screw-top jars. One of the earliest observations of their intelligence is a curious tale where lump fish kept disappearing from an isolated tank within an aquarium in England. It took the curators a while to figure out the thief was an octopus, climbing out of his tank at night, crossing the floor, entering the second tank, devouring the fish, and then surreptitiously returning to his own tank by morning!
Cuttlefish have the most beautiful form of communication, transmitting vacillating/undulating waves of light to each other to signal danger, courtship, etc in a visual form of speech, highlighting how different terrestrial animals are in their forms of communication. If we run into ET, it’s highly unlikely we’ll be able to chat audibly with them as speech may well be as peculiar to aliens as cuttlefish flashes are to us.
Like something out of The Blob, slime are another example of how “alien” life on Earth can be when compared with our normal assumptions on the nature of microscopic life. Slime give us a unique insight into how even the simplest lifeforms can have remarkable complexity.
Place an oak flake in the middle of a maze and Physarum polycephalum will find it for you, using the shortest path through the maze, simply by following the chemical attractants given off by the oats as a food source.
If you place slime mold on a map of Japan or the US and place food where the various cities are and let the slime mold spread out across landscape, Physarum polycephalum will optimize the network, consolidating on the best routes between food sources, essentially replicating the actual transit map designed by human engineers.
And it gets better… Give mold a choice and its “decisions” become deceptively human-like.
Physarum polycephalum doesn’t thrive in bright light. In one experiment, researches gave Physarum polycephalum two food choices: 3% mix of oats in darkness or 5% mix of oats in bright light. The mold spread out, taking nutrients from both sources equally even though the richer source was more irritating to the mold. There’s nothing too remarkable about that, but scientists then introduced a third food source: 1% mix of oats in darkness.
Surprisingly, with three choices, the mold made what seems like a comparative decision, and instead of being split between the 3% in darkness and 5% in light as it had previously been, the mold devoted 80% of its effort solely on the 3% in darkness. The introduction of a poorer option allowed the mold to “realize” the best option all along had been the 3% in darkness. Going after the 5% was too costly for the mold, but the slime only came to this point of “realization” when given sufficient comparative options. This illusion of a decision is the result of a biological comparison where the best return/result is unthinkingly sought out by the organism, but that a colony of amoeba could replicate the reasoning of a creature with a brain is quite remarkable, demonstrating the tenacity and versatility of even the simplest of lifeforms.
Dictyostelium Discoideum are even more astounding, starve this colony of single-celled amoeba and they’ll do something beyond belief, they’ll band together to form a giant slug.
And Dictyostelium Discoideum aren’t just huddling together like rugby players in a scrum, they’re differentiating, taking on set roles within their pseudo-slug, with some of the amoebas playing the role of an immune system, policing the newly formed organism for any bacteria or pathogens, attacking them so the newly formed “slug” can live. The slug, in the meantime, takes on a life of its own, searching for light. In this video, it can be seen moving, lifting itself from the surface of the petri dish, and finally transforming itself yet again, this time into a fruiting spore at the end of a raised stem. Like the polymorph in Red Dwarf, if we find even the simplest of alien lifeforms on the moons of Europa, Encleadus or Titan, they may well have this kind of chameleon ability.
Life is astounding. There’s only a handful of science fiction books or movies that come close to anticipating anything like the versatility and interconnectedness we observe in Nature, and yet if life has arisen on other worlds, it will have followed the same basic laws of Natural Selection, so there will be similar levels of adaptation to common challenges. As a science fiction writer, this challenges me to think deeper about the kind of life we might find on other worlds.
Planarians are another example of the unpredictability of life. These simple flat-worms are hunters with a difference, with their pharynx/mouths secreting digestive fluids before eating their prey, only their mouth also doubles as an anus. Although they have brains, eyes and complex body organs, you can slice and dice a single planarian into hundreds of sections and they’ll all rejuvenate into entirely new planarians. In one simple creature, there’s a level of sophistication and versatility science fiction writers struggle to emulate when imagining alien life forms.
Life on Earth never ceases to amaze me. From a gecko climbing a wall utilizing the Van Der Walls nuclear force without ever realizing it, to bats locating insects on the wind with sonar they never consciously built, it seems there’s no limit to how evolution has honed life on our humble little planet. If we find life on Mars, Europa, Titan or Encaledus, there’s one thing for sure, it will surprise us with its versatility and resourcefulness.