An introduction to concepts.
Ambassadors of Life. R.Licht 010925
Introduction.
Life has been around for 4 billion years. All this time Life has been limited to a space known as the biosphere. Basically, this is a shell with a width of only 10km around the earth’s surface (5km up, and 5km down from the surface) where Life can exist.
For a system to function uninterrupted for such a long time in such a limited space requires certain attributes. One of which is the ability to quickly adapt to changes in the environment and capitalize on new opportunities. Emergent from this drive for flexibility is intelligence, which can adapt on very short time scales. This cultural (as opposed to genetic) transfer of adaptative behaviour tremendously increases the flexibility of Life. We humans are a prime example of cultural learning which leads to flexibility on these short time scales. Most importantly, it leads to the seizing of whole new opportunities not open to Life before.
With our appearance, Life now has created the potential to spread beyond its traditional boundaries. For some years now, people have been continuously living in space. And with private enterprise entering low earth orbit the riches and possibilities of space are now opening up to us. Moreover, the (bio)technology created by humans is now capable to change Life down to its genetic core. Whole new adaptive solutions that do not have to prove themselves in Darwinian terms of survival are now possible. Post-Darwinian Life is on the brink of expanding into unprecedented realms. Especially when we consider that Life is foremost an information system. And information can be coded into carriers other than DNA and brain cells.
Being limited to one planet is dangerous. Life was lucky to hold out for so long on this one spot in space, and time. The spread into space might be one of the best moves the system of Life has produced to ensure its longer-term survival. We are part of the system of Life and owe our existence to it. And from Life’s perspective we could be considered its finest product. Even though our appearance has cost the biosphere dearly in terms of loss of diversity, and the loss of resources. But if we would be the salvation of it, we could make amends.
We should go into space for ourselves, but also as ambassadors for the system of Life. The first will probably be driven by capitalist incentive, but the latter will give us purpose. Society is looking for new meaning now the old ways of making sense of our existence have become obsolete.
On Life, and death.
Life is something we think we know when we see it. However, a good scientific definition is lacking (https://pmc.ncbi.nlm.nih.gov/articles/PMC10123176). This is because many Life-like entities, such as viruses, defy the boundaries we currently have of what is alive and what is not. The same goes for death.
Technology has made it much more uncertain when death has actually occurred. Death used to be simple, if your heart stopped that was it. Modern methods like CPR can bring people back from what used to be certain death (https://en.wikipedia.org/wiki/Cardiopulmonary_resuscitation). That is why it so cool to be a Docter, you get to play God.
In fact, after a person’s death stem cells can still be isolated and grown in the lab to make all kinds of living tissue. In principle, these cells (or more precisely, their DNA) can be used to clone that individual (https://en.wikipedia.org/wiki/Cloning). If DNA is still available, we even can bring organisms back to Life that have been dead for millions of years. That why it so cool to be a scientist, you are a God.
Therefore, a new paradigm has to be found. One that does not try to erect a boundary between what is alive and what is not, but assumes Life is a gradual consequence of the natural laws that govern the universe. Here physics leads to chemistry which leads to biology which ultimately leads to something we identify as Life. In this scenario, Life is just emergent from how the universe functions (https://en.wikipedia.org/wiki/Emergence). So, there is a continuum of processes, some of which we would identify as alive (a human) and some not (a virus). In this paradigm, if something is alive or not becomes a matter of taste.
Importantly, this new paradigm leads to all kinds of novel ideas on how to spread Life throughout the universe.
Entropy
Even though nature seems amenable to Life
some natural laws at first glance seem to conspire against the emergence of Life. One of these is entropy (https://en.wikipedia.org/wiki/Entropy). In the universe, disorder is favoured over order. Therefore, there must be ways in which emergent processes can overcome entropy. In fact, even use entropy to their advantage.
Life has been famously described by Erwin Schrodinger as an anti-entropic system (https://en.wikipedia.org/wiki/Entropy_and_Life). The only way a system can be successful at fighting entropy for billions of years is if the material parts that are subject to entropy can be replaced. Therefore, a system that operates in deep time (https://en.wikipedia.org/wiki/Deep_time) needs to be based on information. That system further only needs free energy to allow it to fight entropy.
Life constantly needs free energy to resist entropy, and to build order. Not only to maintain the information system, but also concentrate information. Only when free energy will run out, Life will inevitably cease to exist (https://en.wikipedia.org/wiki/Heat_death_of_the_universe)
And free energy is actually provided by entropy. Energy only flows because it seeks disorder. Just as a hot cup of tea becomes drinkable because of entropy, high energy radiation (visible light) from the sun is transferred into low energy (heat) which powers the anti-entropic nature of Life. Life thus uses entropy to drive its orderly state. In fact, Life might be favoured by the universe, because it is such an efficient entropy enhancer. It actively uses energy, and is thus speeding up entropy (https://www.quantamagazine.org/a-new-thermodynamics-theory-of-the-origin-of-Life-20140122/)
Information
Importantly, any form of Life is necessarily temporary in the context of the second law of thermodynamics. Otherwise, it would, in the long run, violate the second law of thermodynamics.
Also, individual Life being a temporary phenomenon derives from logic. Consider the Life of an individual human. However well adapted and skilled you are, there will always be a virus, a predator, an accident or a war that will kill you. And even if you live very long, a changing climate or asteroid strike will eventually kill you. The existence of any individual is limited in time (not considering technological developments, for the moment). Thus, for the system of Life to work in deep time there needs to be a way to replace the inevitable decline of the individual. We do this by producing copies, better known as children.
The birth of a new human is the transplantation of (slightly altered) information into a new temporary physical substrate. The system of Life can only endure because it is not just a physical system. It just uses physical attributes to manifest itself. Life is also an information system. However, there needs to be a constant presence of substrate (atoms, molecules, cells, humans, species) to code the information. Information needs a matrix. Therefore, Life can be considered to be both an information and a physical system. Importantly, the transplantation of information to new generations is not perfect. This allows for tiny changes that will drive development through evolution (https://en.wikipedia.org/wiki/Evolution)
Again, consider the Life of an individual and very complex human being. It is difficult to explain the occurrence of such a very low state of entropy occurring directly out of the natural laws that govern the universe. Even though they allow for complexity, that much complexity is highly unlikely to appear at once. Much more likely, is the gradual build-up of complexity from a basic, low complexity starting point. Only a first self-replicating molecule is required, which then grows in complexity through evolutionary processes. The laws of nature are not compatible with the sudden occurrence of very complex humans. Also, an evolutionary system of growing and adapting complexity leads to development in lock-step with changing circumstances. It seems to be the only way in which a system is robust and flexible enough to survive for billions of years.
Life thus, for a large part is information technology. An important part of that information is coded in our DNA (the rest in cell connections). DNA has four letters (ATCG). Computers two (0/1). But their basic coding is principally the same, and is compatible on the level of information processing. Life is IT, and can be combined with other man-made forms of technology.
Life, in this new paradigm, is thus emergent from the behaviour of individual atoms, molecules, cells, organisms and species. Importantly, each of these physical parts is expendable. And so are you. Replacement of parts is constant, so that the emergent system can remain. To do so, it just needs energy and information.
Aliens
But then, when Life is a logical consequence of nature; where are all the aliens? Apparently, Life has some bottlenecks. Especially intelligent Life might not be common. At this point we have to assume we are relatively special. Another good reason to cherish, and spread, the Life we know of.
Life pretty much got started on earth as soon as conditions were ripe, after just a few 100 million years of the existence of the planet. However, it did not develop into the complexity we see today for billions of years. These facts already suggests that Life is easy to start, but complex Life isn’t. We have identified a few of these bottlenecks for advanced complexity, like free oxygen and endosymbiotic events (https://en.wikipedia.org/wiki/Great_Filter). But these will occur, apparently, when there is enough time. For this you need a stable planet and solar system. This is what seems to be rare, as far as we can now tell. We really should appreciate more the benign circumstances provided by our planet’s plate tectonics, magnetosphere, our moon, type of sun, conveniently placed gas giants and even place in the galaxy.
Cooperation
Even though life was stuck at a single cell level for billions of years does not necessarily mean there was absolutely no complexity to Life. Bacteria already have DNA, ribosomes and proteins. Not to mention complex energy harvesting mechanisms. Therefore, when a single bacterium already has all the intricate machinery to do everything required to live, one can argue that the big leap from bacteria to humans is more one of cooperation than of complexity.
In fact, having to do everything yourself was holding back further development of complexity. For example, energy harvesting from the environment is more efficient the smaller you are because of diffusion (https://en.wikipedia.org/wiki/Diffusion). Only when life’s core activities were shared between specialized organisms (later becoming organelles) could Life grow bigger and ever more complex.
This had a very interesting side effect. When, for example, there are multiple specialized parts one can remove/repair badly functioning parts while keeping a functioning whole. Life ran away with this principle and very complex, multicellular life now exists only of parts that can be replaced. Everything in the body is replaced at some point. Another illustration of the fact that you are not your physical attributes per se, but only how these generate your emergent self.
Modularity
The most efficient method Life has developed to repair itself on the go is by using Stem Cells https://en.wikipedia.org/wiki/Stem_cell). The human body is made up of billions of cells, of which no cell is crucial. Therefore, when there is damage, even to a cellular subsystem of the cell like the DNA, the whole cell is replaced (https://en.wikipedia.org/wiki/Apoptosis). The cell is still the basic module of Life and cell division the easiest (and oldest) way of recycling Life’s physical parts.
However, if the cellular replacement system gets out of control, and too many cells are produced we call this cancer. To prevent cancer this system of cellular renewal is strictly controlled, and not as prolific as required for full replacement . This is one of the reasons we age. In fact, be happy that you age, otherwise you would have died of cancer many years ago.
Modularity is the basis of many therapies, mostly involving stem cells. Because every cell has all the DNA, it is possible to regrow most cells in the body from a single (stem) cell. In fact, all of our bodies grow from a single, omnipotent stem cell; the fertilized egg.
This would also be a good way to travel between the stars, just send frozen fertilized eggs and let them develop once the destination is reached. No need to send whole humans. Not only because of space and weight considerations but also because whole organisms do not freeze well. To keep whole humans alive for centuries requires spaceships on the scale of cities.
Giant spaceships are still a good idea though; we should go live in space in self-sustained city sized space ships. Why live in a gravity well when you can avoid it. But not feasible on the short term, or for seeding the universe with life.
In fact, when seeding the universe with Life the concept of sending (stem) cells can be complimented with other technologies. Especially when we stop being self-obsessed by human Life. For example, sending fertilized frog eggs, beetle eggs and some algae to a planet with standing water might be enough to kickstart an ecosystem.
The technologies of Life
The very first development of Life had to be an information system. Probably RNA at first, a relatively simple single stranded molecule. Later followed by the more robust, double stranded DNA (https://en.wikipedia.org/wiki/DNA). Because RNA is single stranded it can still flex and bend in on itself producing a 3D-structure, much like proteins. In fact, many RNA’s today still have protein-like functions, such as the ribozyme. Therefore, RNA can double as an information carrying molecule and an enzymatic molecule. This allows for a self-replicating structure.
The development of an information system allowed for evolutionary forces to select for more and more efficient and robust self-replicating systems. But the development of DNA required the development of true proteins because DNA does not have the flexibility to also function as an enzyme. Proteins are much more versatile than DNA/RNA and apart from functioning as enzymes can also build structures. However, proteins are made from different building blocks then DNA. Where DNA uses 4 bases, proteins are made from 20 different amino acids. This is the major reason proteins are so much more versatile than DNA/RNA. But the use of two separate systems required an elaborate translation machinery, to get the code from DNA converted to the code of proteins (https://www.genome.gov/genetics-glossary/Central-Dogma). Interestingly, this translation machinery is made of proteins.
Amazingly, if you can purify the proteins that do the (transcription and) translation, you can perform these basic steps in the laboratory, in a test tube. This leads to the philosophical observation that the basic processes of life do not need a living cell, perse. More practically, this means that, in the lab, all of the genetic code is now readable and changeable as much as you want.
Where Life only accepts changes in the code that are beneficial for evolution, science is now only limited by imagination. If we imagine we want to make life that can live on Mars, for example, we are able to. The only real limit is the availability of enough free energy, building materials and a benign temperature/pressure environment that allows for a liquid solvent (water).
On a deeper level, the translation of the 4-letter DNA (and mRNA) code to the 20-letter protein code is exactly that; a translation. This means the codes used by Life are interchangeable, much like different alphabets, or computer codes. If we think of the RNA and DNA as information systems, Life becomes IT. And the sky is the limit.
Also, regarding life as an information system means the combination of man-made systems and the systems of life are compatible. Better still, Life is also an electrical system.
Electricity
The second development the earliest forms of Life had to make, after an information system, was a harvesting system for energy. It is logical to assume Life started in an environment where there was a plentiful supply of free energy. Most scientists now agree that this was around volcanic cracks in the earth’s crust. Here, ions seep out from the earth’s interior. Ions are charged atoms, positively charged when lacking an electron or negatively charged when they have more electrons than protons. Many of these ions were generated during earths formation and to this day seep out from within the earth into the biosphere. Importantly, when charge flows it generates electricity. In fact, the earth can be considered to be a giant battery, which the fledgling systems of Life probably tapped into. To this day, the basic mechanism by which cells function is the flow of charge (in the form of ions) across their membranes. We are electrical beings.
This means Life and man-made technology are compatible on this level as well. The only difference is that our technology is based on direct electron flow, in semi-conductors. But the basic principle is the same. Therefore, if we want to enhance ourselves in ways that make it possible to live outside of earth we can do this on both the information and electric level. We then need to become cyborgs.
In fact, we already are cyborgs. Glued to our phones and totally reliant on the internet we are now very much dependent on our biological and technological systems working together. It is just that the systems of Life and the systems of Technology are not fully integrated as yet. We still need interfaces, mainly in the form of screens. When we can directly connect our (brain) cells to our technology we can, again, become whatever it is we want to be.
And then there is sentience. Current theories assume that our electric nature is how consciousness arises (https://link.springer.com/article/10.1007/s10071-023-01780-3). With our developing complexity, also our electric complexity grew. And thus, our level of consciousness to a point where self-awareness occurred. This development has now brought the system of Life to a whole new level of existence. And as a consequence, Life can now be considered to be aware. And if the universe can be considered to have spawned Life, by the basic rules of physics, it can be argued that humans have given the universe the potential to become sentient.
However, when all Life is electric also all of Life will have some form of sentience. In fact, we know of many animals who are self-aware. And of most Life forms that they are aware to some degree.
Therefore, we should not only try to spread the Life we are most concerned about. Just sending humans out into space is not always necessary, or prudent. There is good reason to start with simpler Life forms. Because we can do this today.