Where Are The Little Green Aliens?

Allan Milne Lees

Apr 29, 2020·10 min read

Why technologically sophisticated species will be vanishingly rare

Thanks to the Industrial Revolution, education systems were forced to adapt in order to meet the growing need for intellectually skilled workers. Over time, and largely by accident, this led to an increasing number of people acquiring the capacity for reasoning from facts. As a consequence, superstition/religiosity diminished among educated people and a more coherent worldview began to take shape.

Today, most Europeans understand that we live in an expanding universe and that all life is shaped by the inexorable forces of evolution. Teleological explanations are therefore ruled out as a means of explaining such large-scale phenomenon.

Unfortunately, we’re still in the very early stages of learning to reason and consequently we still make very basic intellectual mistakes. One such highly revealing mistake is our obsession with the idea that there “must be” many other technological civilizations “out there” for us to encounter at some point when our own technologies permit us to do so.

In fact, this notion is merely a substitute, dressed in Star Trek clothing, for our former belief in angels. Rather than indulging in wish-fulfillment fantasies, it’s more interesting to explore the reasons why technologically sophisticated intelligent life is almost certainly extremely rare in the universe.

We need to begin by acknowledging that we have no rigorous definition of intelligence. Let’s merely say that by intelligence we mean the capacity to reason coherently starting from empirical evidence and moving from there to structured speculation by means of tools such as mathematics.

So let’s look at what it takes for a species to have the fundamental requirements that permit the eventual development of sophisticated technologies that would eventually enable some form interstellar communication.

First of all, it would appear that higher levels of intelligence are strongly correlated with the need to solve practical problems such as securing food, shelter, and mating opportunities within environments that are somewhat unpredictable and varied. Species that are highly adapted to their particular niche don’t have any need to develop higher levels of intelligence because it would confer no advantage to offset the metabolic costs. That’s why sharks and panthers, both highly adapted killing machines, don’t need the intellectual capability to utilize simple tools. They operate largely on hardwired instinct because that’s all that’s necessary for them to thrive in their stable predictable environments.

Opportunists such as corvids and rats as well as some of our own primate cousins, live in environments where adaptability and improvisation can make the difference between survival and death. That’s why we see crows using twigs to extract grubs from the bark of trees and why rats have superb memories with regard to route-finding and navigation. It’s why we see some primates using stones to crack the shells of nuts or washing dirt off tubers before eating them.

But of all the creatures that have ever lived on Earth over the last three billion years, of all the billions of species that have emerged, thrived, and then vanished, only our species has developed sophisticated technologies.

Only one species in more than three billion years.

When we consider how astonishingly adaptable life is, from extremophile bacteria thriving in hot acidic environments to the bats that use echolocation to navigate in total darkness, the fact that only one species in all the history of life on Earth has developed sophisticated technologies is remarkable.

This fact tells us something very important about the conditions that influence the emergence of a technologically sophisticated species: there must be several factors, all of which are critical, that must exist all at the same time. Without every essential factor, nothing happens.

Let’s look at what these critical factors must be, derived from comparisons of our own species with those species that also possess significant intelligence.

The first criterion would seem to be the fact of living in an ecosystem that can accommodate opportunists. This means that developing the mental capacity to spot and exploit novel opportunities will favor the development of some kind of active intelligence. That’s why corvids and rats and some primates have evolved the ability to solve problems.

Problem-solving is useless, however, without some ability to modify the ways in which a creature can interact with its environment. Crows can use beaks and claws to achieve some basic use of twigs; rats can use claws and mouth; elephants can use their dexterous trunks. But none of these attributes is adequate for the development of more complex technological aids.

In most species, higher levels of intelligence serve to enable purposeful coordinated group activity directed most often toward obtaining food but also utilized for other purposes such as creating opportunities for mating. Thus cetaceans clearly exhibit significant intelligence and appear to have developed language; this enables them to form cohesive social groups that collectively enhance opportunities for feeding. This is famously seen in certain dolphins and with Orcas, where pods collaborate to herd fish into conditions where mass predation can occur.

Elephants likewise have developed significant intelligence which enables them to adapt to environmental challenges and to utilize their prehensile trunks to manipulate, to some degree, their world.

But dolphins and whales lack any ability to make tools. Their streamlined bodies have no mechanisms for fashioning implements even if the materials for such things were available in their environments. So cetaceans, while intelligent, cannot go further.

Likewise, there’s a limit to what trunks and beaks can achieve. Only primates have dexterous paws by means of which to engage in delicate tasks such as flint napping, whittling the branch of a tree, or braiding strands of plant material into rope.

So we can see that a combination of a variable environment that has room for opportunism plus the physiological ability to perform delicate manipulations of naturally-occurring environmental resources can give rise to primitive tool-use. As best as we can tell from the archeological record, primates of one sort or another have been making primitive artifacts for over a million years.

It’s not inconceivable, therefore, to imagine that at some distant future time some other species could encounter a similar concordance of environment and physiology. Octopus, for example, have significant intelligence and highly dexterous tentacles. They already take advantage of environmental resources such as discarded shells. So could some future species of highly-developed octopus go on to create sophisticated technologies analogous to our own?

Sadly, the answer is a resounding no.

Aside from the fact that octopus aren’t fundamentally a group species and so can’t pass on detailed knowledge to future generations, there’s only so far you can get with shells and stones and bones. To progress further down the technological highway it’s necessary to exploit chemistry. When we look back on the development of human technologies we see very clearly that the ability to smelt ore was a fundamental breakthrough. Hence we even call certain periods according to the results of this ability: the Bronze Age, the Iron Age. Perhaps we should term today the Hydrocarbon Age.

Whatever we call our human eras, it’s apparent that the ability to manipulate chemistry is essential in the development of sophisticated technologies.

Literally nothing we rely on in our modern world would exist without our capacity to perform astonishing feats of chemical engineering. And that’s why there will never be a hyper-intelligent octopus landing its craft on the surface of the moon. How can one smelt ore underwater? When we consider all the various types of chemical engineering upon which all modern technologies rely, we find that precisely none of them can be developed from scratch underwater or, indeed, in any similar type of fluid.

So there may well be aquatic life in abundance across the universe. Personally, I suspect there’s life in the oceans of Europa and perhaps even methane-based life on Titan. There may be organisms that float high in the atmospheres of gas giants, their body structures analogous to aerogels. But none of this life can ever go on to develop technologically-oriented civilizations. The chemistry is simply impossible.

That leaves us with organisms inhabiting a surface covered by a layer of gasses. In such environments, bodies don’t have to optimize for low drag or niche environments. Appendages can occasionally evolve to enable delicate and complex manipulations. Materials may be available in the environment from which at least rudimentary technologies can be crafted. And of course the species must be highly social, otherwise inter-group communication will be rudimentary. Without complex communication, it’s impossible to pass on knowledge and improve things over time, either by trial-and-error or by purposeful experimentation.

So here we have some of the essential ingredients for a technologically sophisticated species:

It’s a group species that’s opportunistic, taking advantage of novel opportunities in its environment rather than being highly adapted for a particular niche. It lives on the surface of a rocky planet and has dexterous appendages. It can engage in sophisticated communication and ultimately is capable of inventing a way to preserve communication for posterity (we humans call this writing). It must also invent mathematics and use writing to develop this ability to manipulate abstractions to the point where it can first model events and thereafter reproduce them as desired in the real world.

That’s a pretty tall order, and now we can see why only one species among all that have ever existed across more than three billion years of life on Earth has ever propelled machines out of our planet’s gravity well.

It’s why the so-called Fermi Paradox is naïve: it’s absolutely pointless talking about numbers of stars and planets and statistical probabilities. They have almost no bearing on the development of technologically-capable life. Probably more than 99.99999% of all life in the universe can never develop advanced technologies of any kind because one or more essential factors are absent. And remember: all the factors must be present simultaneously in order for technological progress to be possible.

Now, given the vastness of the universe, even a 0.00001% possibility means that there are most likely many other technologically sophisticated species “out there.” But the universe is a very, very big place. Starlight from the Andromeda galaxy, our nearest neighbor, takes more than two and a half million years to reach us. Even the most optimistic Trekkie can’t propose a conversation that takes more than five million years to exchange a simple “hello.”

And as for physical travel, why would any species embark on a one-way trip lasting tens of millions of years in the vague hope they might just, possibly, somewhere, encounter some other analogous species after arrival? Even fantasizing about advanced cryogenics, ion drives, or organic-electronic interface lifeforms doesn’t really solve the problems of distance. Warp drives and subspace communication are plot devices, not physics. The universe is simply too big for us to fall back on statistical probabilities. Almost all life in the universe is thus forever beyond our reach, no matter how amazing our future technologies may be.

So let’s restrict our remit to our own galaxy, a mere hundred-thousand light-years across. But even this is too large, because we have no practical way of communicating with any star system on the other side of the galactic disk. Because of interstellar dust we can’t even see most of our own galaxy, never mind communicate with it. So now we’re limited to line-of-site. Given human lifespans and the massive social and political changes that occur within mere decades, we’re probably limited in practice to an imaginary sphere some 60 to 100 light years in radius with us at the center. It’s just possible to imagine communication that only takes two hundred years to exchange a quick “hello.”

Current estimates indicate that means there are around 14,000 stars close enough for such potential time-lagged communication. That’s a tiny number. Even if we hope that every single one of these stars is surrounded by planets, and that at least 20% of these planets could harbor life of some sort, the odds are not looking good. Not only is the probability of technology-capable life evolving within this small group vanishingly small, but the probability of any such technological species overlapping in time with us is even smaller.

Remember: we’ve only had space-capable technology for less than one hundred years and the strong probability is that our civilization will collapse within the foreseeable future. Any similar technologically-capable species likely faces similar constraints. And even if we were to survive as a species for an unlikely million years, that’s the blink of an eye in evolutionary terms.

Our species emerged only after more than three billion years of life on Earth and any analogous species likewise probably will take considerable time to emerge. So the chance of us overlapping in time within our 100-light-year radius is essentially zero. The probability doesn’t improve in any meaningful way even if we double the size of our radius and thus increase the potential number of stars eight-fold to 112,000.

The fact is, the odds are heavily weighted against us no matter how we play with the parameters.

Sure, we can invent magic stories about organisms merging with eternal machines, but these are no different from inventing stories about Zeus or Zeb or fairies. They don’t address the real issues we must confront when we think about the possibility of an intelligent technological alien species interacting with our own. I would very much like to be wrong about all of this, but facts and reason tell me otherwise.

Therefore while it’s charming to imagine encounters with little green aliens and harmless to spend an hour watching some naïve televised entertainment featuring cowboys in space, the sad reality is that we are to all intents and purposes utterly alone in the universe.

And perhaps that’s just as well, for homo sapiens is not really particularly intelligent, we panic at the drop of a hat, we’re incapable of coherent reasoning and rational behavior, and we’re incapable of managing our environment. All we do is squabble and bicker and use our technologies to create ever-more-ingenious ways of harming each other.

We would make a very poor galactic neighbor indeed.