There is a confusion when we use the word 'alien'. We have been conditioned by fiction to think of intelligent aliens when we hear the word alien. In fact this article is using the word to mean any form of life not originating on Earth.

At each level of the organism there will be mechanisms in place to eliminate conflict, maintain cooperation, and keep the organism functioning.

That sounds awfully close to the Gaia hypothesis, which simply asserts that everything is ultimately at balance all the time - that even viruses, germs and cancer have some ulterior purpose in the homeostasis of life.

It doesn't count for the fact that natural selection doesn't care if -you- survive, or that any particular organism resolves its internal conflicts. It only matters that it survives long enough to reproduce, and that reproduction as a species doesn't need to be a stable system either - it just goes on as long as it may.

All the organisms are "broken" in this sense - none of them are in balance or conflict-free, or ultimately "functioning" - they're simply there because they haven't died out yet.

Any alien that makes it to earth will have overcome all the same physical, engineering, and technological challenges that we faced to get to the moon. And thus they may look different, but they will share so many physical and mental features with us, that we will have no problem understanding them. Perhaps less than a lost Amazonian tribe faces when it meets modern culture for the first time.

This is why I wrote an essay 3 years ago titled "Why Artificial Intelligences Will Never Be Like Us and Aliens Will Be Just Like Us." (27 June 2014) http://jayarava.b...ver.html

Convergence will make "aliens" entirely comprehensible. However, if we are talking about finding non-terrestrial life, say in the subterranean sea on Enceladus, then there is no reason why it will be like life on earth, except that it must be based on chemistry and chemistry places the same limits on it that it does here.

There is a lot of confusion such as implicitly assigning levels to complexity, which is problematic. Parasites often have decreased bodily complexity and increased lifestyle complexity. In 4 Gyrs of evolution, no complete sexual symbiont as envisioned here has evolved, which I note we can tell the low likelihood from by ordinary biological "mechanistic" means. And I cannot see that the article is published yet. Samuel Levin is a student "broadly interested in social evolution, the formalization of the theory of natural selection, and philosophy of evolutionary theory." [ https://www.envir...l-levin/ ] I reserve my judgment until publication.

@Eikka: Yes, that too. I am sorry for my unintentional down vote, I was aiming at 4 but the web page GUI is unforgiving, I seem unable to correct.

Hollywood films and science fiction literature fuel the belief that aliens are other-worldly, monster-like beings, who are very different to humans.

Really? In most movies aliens are vaguely humanoid (because until recently you needed an actor to slap some paint onto underneath) and also invaribaly almost human size (because filming interactions between a human and a mountainous creature or a human and something the size of a single cell organism is rather hard).
Oh...and they also had to be sexy a lot of the time.

If anything Hollywood films have been remarkably dull in imagining aliens.

As for evolutionary theory. That only helps if you positthe environment it works in, first. The environment selects (and also the interaction between individuals of a species once they start having an impact on the environment - like making a dent in the food supply. at that point you get intra-species competition.)

What we can assume about intelligent extraterrestrial life: it will have some means of perceiving its environment which makes it possible to understand its location and spatial relationship with other objects, it will have some means of directly manipulating its environment, it will have a mind capable of understanding its environment as well perceiving its own existence. All else beyond those things is wholly unpredictable; life adapts to exploit environmental conditions and thus will take whatever shape is most advantageous. And I suppose it's reasonable to assume that its simple tools will bear at least rudimentary similarities to our own simple tools --prybars, probes, cutting implements, etc.

Despite all the wishful thinking (some of which are actually sensible) in the comments.

This 'article' is nothing more than an outline for a comicbook or an animated cartoon.

Watch out for those copyright infringements!

The truth is still out there read Codename Angel

I think any form of life not a complete replica of something found on Earth will still stimulate the same part of the brain when viewing fictional representations of alien life. That awe of unfamiliar life forms.

Technology is probably essential to the emergence of sentience. Technology is the externalization of evolutionary adaptations. Instead of evolving better fangs and claws we create knives and spears and so no longer need fangs and claws. Instead of fur we make clothes and build fires.

This allows our bodies to be more efficient in allocating resources to support bigger brains, which in turn can invent and use better tools and weapons, as well as participate in more complex societies.

Using tech requires rigid limbs which can exert opposing forces and carry heavy objects. Opposing limbs can pound, hack, saw, twist, and pry materials. They can knap flint, cut firewood, sew garments, and eventually turn screws.

Screws are essential to complex machinery which must be assembled and disassembled for repair.

So we can expect sentient beings to have at least 2 limbs for motation and 2 for manipulating materials, as well as the binocular vision of predators.

BTW the chemistry of silicon means that anything as complex as life being based upon it is so unlikely as to be easily discounted. More or less the only stable silicon compound is silicon dioxide and that won't react with anything. Everything else is highly unstable, especially in the presence of even a mild oxidiser. Chemistry and thermodynamics are the same everywhere in the universe.

@TheGhostofOtto1923 - how do you explain the sentience of aquatic mammals then?

Otherwise I agree. Classical mechanics principles apply everywhere on the scales of mass, length, and energy we are talking about. Levers and fulcrums, grabbing and holding, applying energy, these are all universals. Getting into space requires any organism to live in a particular kind of environment and to solve a very particular set of engineering and technical problems.

For me metallurgy - from primitive minding and smelting, to blacksmithing, to the production of high-tensile strength, high melting-point alloys, is the iconic range of technologies. It requires certain abilities as you describe. Without it no alien will ever get into space, let alone cross parsecs to get to us.

Our limbs evolved to propel us from branch to branch and later to run between trees and across open savannah. The overhead motion of hand to hand swinging and climbing gave us arms which were uniquely configured for throwing rocks and spears overhand, and for wielding clubs and pounding materials and food.

It gave us the ability to kill dangerous animals at a distance. It enabled us to clear the forests and fields of the predators which had been hunting us and keeping our members in check.

Once we crossed this threshold, our principal enemy became the people who wanted the same food we did.

Humans began to assemble in ever larger groups for protection. Natural selection began to give way to group selection, and individual fitness yielded to the ability to contribute to the fitness of the tribe.

Any species which began to eliminate their attritive elements through technology, wherever we may expect to find them, would have had to follow the same path that we did.
cont>

This includes technological innovation, overpopulation, group selection, science. Our main disadvantage was that our repro rate has not changed since the beginning of the pleistocene. It made overpopulation endemic, and all the horrors and benefits that go with it.

Through enhanced conflict our brains swelled and our knowledge of the universe accrued.

how do you explain the sentience of aquatic mammals then?

How do you explain the absence of technology among your 'sentient' aquatic animals?

Perhaps octupi could one day fashion pointy fishbones and build rock fortifications but they would first have to kill the fish that eat them.

For me metallurgy - from primitive minding and smelting, to blacksmithing, to the production of high-tensile strength, high melting-point alloys, is the iconic range of technologies. It requires certain abilities as you describe. Without it no alien will ever get into space, let alone cross parsecs to get to us

You bet. and this would have to take place in an environment that allowed combustion. Its hard to imagine metallurgy without fire. Maybe clever cephalopods could figure out how to use volcanism but they would first probably have to experience a long history of intertribal competition before exploring that avenue.

The downfall of neanderthal may well have been that their repro rate had begun to adapt to their temperate and subarctic environment, becoming seasonal. As a result their intertribal competition began to wane and when the cromags arrived, the neanderthal couldnt replace battle losses as fast as the tropical interlopers nor match their advanced weaponry and tactics.

As a result they were outgrown and overwhelmed.

Extraterrestrials have been encountered by humans on earth for millenia. Christopher Columbus made note in his ship's log of candle-like craft emerging from the sea's surface. Actual face-to-face encounters with extraterrestrials are well documented from around the world.
Since most of you need a peer-reviewed paper to believe anything, these beings aren't in the habit of allowing themselves to be tested. It's actually the other way around, which has been known, under lock and key, by governments for a very long time.

While it is logical that living forms would subject to natural selection - in fact would likely not be living if they weren't - the article persists in the fallacious assumption that "evolution" is progressive and that we are "... evolving to be fitter and stronger over time..." That's drivel. Selection acts in the moment and has no awareness of future needs.

Any alien that makes it to earth will have overcome all the same physical, engineering, and technological challenges that we faced to get to the moon

Well yes, for their very first voyage off their own planet, which in our case used combustion engines and carried Captain Bligh's sextant for navigational backup. But to get here they must do interstellar travel, so their early fire-and-sextant space technology will likely be as tiny an influence on their travel here as chimps' bug-fishing twigs are a tiny influence on nuclear weapons.

Extraterrestrials have been encountered by humans on earth for millenia. Christopher Columbus made note in his ship's log of candle-like craft emerging from the sea's surface. Actual face-to-face encounters with extraterrestrials are well documented from around the world.
Since most of you need a peer-reviewed paper to believe anything, these beings aren't in the habit of allowing themselves to be tested. It's actually the other way around, which has been known, under lock and key, by governments for a very long time.

While I admit you may be right your comment does say one thing pertinent to the article. That if they are already here then they have to ability to adapt to our atmosphere which suggest that there own native atmosphere/environment/evolution isn't that different from our own. But being a 'romantic rebel' I like to think of ET as life as we DON'T know it, Ha!

Gotta love me some fanciful pontification regarding the pseudoscientific mumbo jumbo of astrobiology. Some like to consider astrobiology a legitimate science but the search for bigfoot is more legitimate. Hell, the hunt for leprechauns and unicorns is more legit.

Is it only me or does the rightmost alien of the first image depict a member of the Great Race of Yith?

Have these scientists by chance seen this image in a dream? And most importantly, were there any other creatures in that dream? Maybe some visions of a sunken city, or (may God keep my sanity) a hint of a creature of vaguely humanoid shape, winged and with tentacles where it's face should have been?

Were this the case, gentlemen, I am afraid that He Who Sleeps Eternally make be close to awaken.

Many here share common ancestry with them as they 1st came here 22million years ago from the Lyra System, sun Vega.

Ah, yes. The Vegans are nice people, I love their cuisine, But the people from Lyra are kinda annoying to have as neighbors, specially when they practice playing their national instrument, the Lyre.

Extraterrestrials have been encountered by humans on earth for millenia. Christopher Columbus made note in his ship's log of candle-like craft emerging from the sea's surface

Yes, that's totally true and documented. The newer models of spacecraft were however light-bulb shaped, this was abandoned for more environmental friendly CFLs or LED which also allow the spaceships to be made in more fancy colours and designs.

Selection acts in the moment and has no awareness of future needs.

Exactly. Evolution can go round and round in cycles. This has happened several times in the history of predator-prey relationships, where prey developed ever tougher hides to the point of scales and plates (at the cost of becoming slower) while predators evolved larger jaw muscles and longer teeth/claws (also at the cost of speed due to increased mass. If you look at something like the sabretooth tiger then that thing could hardly sprint).
At which point prey evolved to be faster/lighter causing predators to shed mass and the cycle started all over again.
It didn't lead to exactly the same organism each time around, but the record shows that there was no one direction towards armor/teeth/speed/size/whathaveyou where organisms evolve to continuously.

Predictability only works in a static environment. And by all we know environments are anything but static over the course of history.

So we hear sound of silence in space?

Maybe we're just looking for heliographs where people have invented the telephone?

Or they are just getting smart and not broadcasting stuff to places where it doesn't matter? Even we are starting to figure out that when you want to convey information from A to B it's more efficient (read: cheaper) to do a directed broadcast instead of blasting it in a 720° arc.

Especially across large distance you want to do directed broadcasts, otherwise your power needs explode. And since we're not of interest to them why would they even broadcast in our direction? There'd be no point to it.

Moreover if they have even close to light speed travel then sending information pods is a LOT better in terms of certainty that the information will arrive and not be overheard.

The universe could be filled to the brim with information shuttle traffic or directed EM broadcasts and we'd never see it with our current 'eyes'.

If any alien beings were reading these comments? The gales of laughter would be cosmic!

It has been penned; that if wishes were horses, we'd be up to our eyebrows in manure! And here we all with a long list of steershit commentaries.

Osiris1 "Strictly speaking, all life brings some order out of chaos, the reverse of the entropic principles from engineering."

"Strictly speaking" this is wrong. Because earth has life it is better at turning low entropy sunlight into higher entropy heat. For every photon of visible light that falls on the earth, life radiates 20 photos of infra-red light back out into space. This is much more efficient that any other planet we know of. Overall entropy always increases, even more so in the presence of life.

There are now many different arguments for complex chemistry being the thermodynamic path of least resistance in the environment of the early earth. The reverse Krebs Cycles, for example, is just bucket chemistry - throw in the ingredients, and at a given concentration the reactions spontaneously take place producing more complex organic molecules. This could easily have occurred at the sites of warm alkaline undersea vents.

@TheGhostofOtto1923 to confuse sentience with technology use is just silly. Dolphins are clearly self-aware and have very similar kinds of social structures to us. They share the fundamental qualities of empathy and reciprocity that Frans de Waal identified as fundamental to primate societies. The fact that they lack technology doesn't change the fact that they are sentient. As are all of the great apes, elephants, dogs, and some birds (so far as we know). Sentience may well even be universal in mammals and birds.

Otherwise I think we agree on the role of tech in the evolution of any space-faring species and the parallelism that this would inevitably lead to.

to confuse sentience with technology use is just silly

-Well lets find out...

"Sentience is the capacity to feel, perceive, or experience subjectively. Eighteenth-century philosophers[FULL STOP]

-Hmmm perhaps you're right. A corrupted term which could apply to just about any animal or machine.

How about sapience then?

"Wisdom or sapience is the ability to think and act using knowledge, experience, understanding, common sense, and insight. There appears to be consensus that wisdom is associated with attributes such as compassion, experiential self-knowledge, non-attachment and virtues such as ethics and benevolence..."

-A virtual stew of indecipherable philo doublespeak.

Perhaps knowledge-recorders and tool/weapon users is better-

Dolphins are clearly self-aware and have very similar kinds of social structures to us

Really? Dolphins have sports teams, PTA, navy seals, communism, investment banking, monster truck rallies?

'Self-aware' is when a fly perceives your hand approaching to squish it, and flys away to protect itself.

Combing our hair in a mirror or praying to a god is just another degree of complexity.

Any attempts to make it more complicated than that is philo perfidy.

We Humans brag of being sentient and sapient....

While our actions are the most stupid of self-destructive misbehavior.

So the paper has been published, and it is neither problematic nor very exciting. In essence it poses that life everywhere will be products of evolution and cell theory, which is existing astrobiologist consensus, though it embellish it - unnecessarily in my opinion - by abstracting the subject.

So the paper has been published, and it is neither problematic nor very exciting. In essence it poses that life everywhere will be products of evolution and cell theory, which is existing astrobiologist consensus, though it embellish it - unnecessarily in my opinion - by abstracting the subject.

Strictly speaking, all life brings some order out of chaos, the reverse of the entropic principles from engineering. That ought to get a discussion started.

Not that old creationist drivel again, clad in nauseating religious pseudoscience and false claims to make *sure* the discussion stops right there. Besides what Jayarava notes, obviously life as everything else obeys thermodynamics (which is physics, not engineering) , it obeys it precisely in the way of engineers: organisms are fridges! ("Freezing" order inside by radiating heat on the outside, driven by internal heat machines of cell metabolism.)

More science, less superstition and/or false claims on nature, please!

(((Levin)))