One of the more terrifying concepts in science fiction is the idea that some kind of extraterrestrial
contaminant, a microorganism or virus analogue of alien origin that could somehow be delivered
to earth and then move on to infect life here.
The most famous example of this within science fiction is perhaps Michael Chrichton’s 1969
novel The Andromeda Strain, but this concept is also deeply rooted in human history where
different groups of people coming into contact with each other caught diseases for which
one group had immunity, and the other did not.
But there is an important distinction to make there, those incidences, which still happen
today when uncontacted or isolated tribes of humans come into contact with our global
civilization, happen because we’re all still homo sapiens and are genetically very similar
across the entire species.
This opens all of us up to human viruses, yet the overwhelming vast majority of viruses
that exist on earth, do not infect humans.
The reason for this ultimately is that viruses are very specialized in just what they can
do on a chemical and biological basis.
You can have them jump species to a degree, but only rarely, and very situationally.
As a result, if alien viruses exist, and there’s no guarantee of that, they are likely to be
specialized to an alien biosphere and its genomes.
Assuming panspermia exists, and something like a virus can survive the conditions of
interstellar space, or for that matter interplanetary space, then earth is no stranger to alien
viruses.
They have likely been deposited here before and there is no evidence that anything on
this planet has ever been infected by one, or for that matter, there is no evidence such
a thing has ever landed here contained within a meteorite.
But even if it did, it might not last long in this environment and may never find a way
to replicate.
If that’s the case, we’d never come across it.
There have in the past been some fringe hypotheses that all viruses originate from space, but
this has not been borne out.
Rather viruses appear to have co-evolved with life on earth from the very start, and may
have played a role in the early evolution of microbial life on this world.
It’s even conceivable that this could represent a solution to the Fermi Paradox, that solution
being that worlds that do not have pressure from viruses do not produce life above the
microbial level.
In which case we live in a universe of microbes without viruses, and only here did we get
lucky by having both an abiogenesis of life, but also an abiogenesis of sorts for viruses.
If you get one without the other the magic simply doesn’t happen.
On the other hand, there is also the direct contact scenario, where the aliens land on
the whitehouse lawn and some extraterrestrial pathogen is transmitted to us, or we transmit
something to the aliens War of the Worlds style.
This too is unlikely.
First you’d need basic commonality in biochemistry.
There’s no guarantee an alien could breathe our atmosphere for example, most likely they
could not directly do so, thus would need to isolate themselves in their equivalent
of a space suit.
They’d also likely know of any risk biologically, being advanced enough to travel the vast distances
of space, and would take measures to prevent cross-contamination of biospheres.
In fact, alien life may be so different that they don’t even function solely on water,
but rather incorporate ammonia also as a solvent for the chemistry of life.
Could an ammonia based organism live long in the environment of earth?
That seems unlikely.
So some kind of isolation would be key in an actual direct first contact scenario.
Another option is that the aliens are super-immune to everything by virtue of their technology.
In principle, it may be possible to create an artificial immune system impervious to
everything using nano-technology and advanced biotechnology.
It may even be that viruses on worlds eventually go extinct through technological development.
We already do this to a certain degree, we have nearly eradicated or mitigated some former
scourges of humanity such as the black death or smallpox.
Malaria has been controlled in some areas of the world where it used to be a serious
problem, and polio is likewise mitigated to the point that it’s now rare, whereas decades
ago it was far from it.
This trend will continue for us, as we gain greater control over infectious disease.
We’re obviously not there yet, but there may be a day where infectious disease no longer
occurs, and that may be the case for alien species and they may in fact be so super immune
that nothing on this earth can infect them, whether virus or microbe and they can’t
carry anything here from their planet of origin.
And that could be an infection in and of itself.
If you come across an alien, say in deep space, and you find some way to interact directly,
or come into contact with nano-technological contamination even from a long dead spacecraft
you might come across, you could end up with alien superimmunity without even realizing
it was happening.
It might be that generalized nanotech is somehow compatible with you on a technological rather
than biological basis, and starts changing your DNA for immunit.
If so you have just come across an entirely new class of malady.
NanoTechnological illness, and it may be far easier for technology to infect in a generalized
manner than biology can pull off.
It could even get confused and eradicate your intestinal bacteria resulting in death.
And it gets worse.
If you were to encounter a covert alien civilization that hides itself from you while it studies
your planet, it could in principle engineer viruses or nanotech to infect you for whatever
purpose they want.
This is something we do.
Biological weapons are one side of this, but there is another.
And it involves the viruses again.
One of the most exciting areas of medical research today is the idea of altering viruses
to cure disease.
This started with vaccines and weakned viruses, but this research stems from a rather curious
observation from over a hundred years ago during the 1918 Spanish flu pandemic.
Doctors noticed that people that had cancer that caught and survived the influenza outbreak
sometimes showed that their tumors temporarily shrank and their overall condition improved
for a time.
These curious observations were sidelined due to the lack of understanding of genetics
and viruses, and the treatment direction went towards surgery and chemotherapy, but the
idea was not entirely forgotten.
In recent years a new avenue of cancer treatment has been developing, virotherapy, where altered
viruses are used to target and kill cancer cells directly, or better yet provoke the
immune system into a response against the cancer opening the way for a potentially complete
cure or very effective treatment in freezing the progress of the disease.
One way of doing this is to have the virus deposit a chemical marker on the cancerous
cells that the immune system recognizes and then goes on the attack.
This therapy is already being used for cancers such as melanoma, and shows further great
promise in many areas of oncology.
But back to the question of alien life, Close aliens may know of this kind of technology
as well, and might use pathogens engineered specifically for the lesser technologically
advanced species they’ve come across to do good or ill, depending on their aim.
Again, there’s no evidence of this ever having happened here, our diseases look fully
natural and earth-like, and if something were here it would probably have acted dramatically
long before now, but the idea in principle is plausible.
As an aside, we could do the same thing, again in principle.
Say for a moment we found that Proxima B was habitable, but not inhabited by any kind of
life.
One way of terraforming a world long term is molecular nanotechnology.
You essentially infect a potentially suitable world for colonization with nanotechnology,
perhaps aided by specialized viruses, and then program it to develop habitability, and
then come back in ten thousand years to another earth ready for human habitation.
Perhaps one function of viruses in this case might serve as a preventative for natural
abiogenesis on autoterraformed worlds.
And therein is a rather creepy solution to the Fermi Paradox.
This one is more of a subset of a proposed solution rather than a new solution in and
of itself.
The core idea here is that we’re early in the game as far as life in the Milky Way,
and it’s still generally rare.
But what also must be taken into account is that if we are early, there could easily be
an even earlier civilization that has a billion or two years on us.
They would be from a time however when civilization might have been so rare that early on that
they might be the only example and that the reason we don’t see them is that they are
simply discrete, but in over all control of the galaxy at large.
They might have chosen to leave us alone, having discovered our world long before we
arose, but still harboring life.
They very fact that life exists on an exoplanet may dictate what that ancient alien civilization
does with a world.
If it finds life, it leaves that planet alone to its own devices to see what comes of it.
But if suitable worlds are found that have not yet developed life, the ancient civilization
may simply put them on ice and prevent life from arising there with the eventual intent
of using those exoplanets to their own end.
Perhaps they might move from one planet to the next exhausting its resources and moving
on to the next candidate, all while leaving inhabited planets alone.
In such a scenario is that the reason for the great silence is that most suitable exoplanets
for life are being artificially prevented from developing it.
This could lead us to a great mystery as we explore and characterize explanets, if we
see perfectly suitable worlds for life, but seemingly without it, then we’d have to
ask are we seeing a technosignature of worlds on ice, or is abiogenesis really that rare
and difficult.
Without cracking abiogenesis in the lab, that could be a question that we wonder about for
decades.
And if abiogenesis does turn out to be relatively easy and straightforward, we’d have to consider
that there is some kind of galactic governor on it.
And that’s all we may ever know about alien life in the galaxy, that it governs abiogenesis
for some reason but ignores us and other previous occurrences of life entirely.
Returning to viruses, all of this assumes that we know everything there is to know about
the possibilities of viruses.
We clearly do not.
And within the depths of speculative astrobiology lies one of the spookiest possibilities out
there.
Generalized viruses.
It’s possible that viruses on planet earth have it easy, and thus can afford to be highly
specialized and targeted.
Earth is a smorgasbord that allows them to get by easily.
But what of a dying world?
In a situation like Mars it may be different.
Think about it, where a planet very slowly loses its ability to host surface liquid water
and thus easy life.
Might desperate viruses, if life had arisen there, become increasingly resilient and generalized
in order to infect any cell they could to keep going?
Ultimately we don’t know, but one recent finding might shed some light on this issue.
It’s in regards to a bacterium that I’ve covered on this channel before, the astonishingly
radiation resistant species Deinococcus Radiodurans, also known as Conan the Bacterium, which can
survive roughly 28,000 times more radiation than a human.
In a paper by William Horne and colleagues, link in the description below, they found
that one of the reasons this bacterium is so resistant to radiation is that it has evolved
the ability to dry out and accumulate protective antioxidant manganese compounds, along with
unique genetic repair systems, and that radiation resistance was favored by that.
But in this case, researchers envisioned whether this bacterium could survive on Mars and how
long it could remain dried out, but still revivable.
The answer is astonishing.
Yes, it could survive indefinitely in a frozen and desiccated state just 10 meters below
the surface of Mars, and it could do it for about 280 million years.
At the same time, it would not fare anywhere near as well on the surface, only a few hours,
probably eliminating the possibility of panspermia from Earth.
The question is, can a generalized virus remain dormant on Mars in the same way.
If so, it would need to be able to do it far longer than 280 million years to get back
to the time when Mars had liquid water, several billion years ago.
But with periodic melting due to volcanism and impacts, it may in principle be possible
for bacteria and their potential accompanying viruses to have survived and could be waiting
for us.
Thanks for listening!
I am futurist and science fiction author John Michael Godier currently concerned about panspermic
Conan the Bacterium.
One of them long ago was busy absorbing something and along comes an asteroid impact flinging
it to Mars.
It gets there and its like well, I guess I’ll just dry out and wait until someone picks
me up.
And along comes a manned Mars mission 100 million years later.
Not good and be sure to check out my books at your favorite online book retailer and
subscribe to my channels for regular, in-depth explorations into the interesting, weird and
unknown aspects of this amazing universe in which we live.