Postbiological evolution is a form of evolution which has transitioned from a biological paradigm, driven by the propagation of genes, to a nonbiological (e.g., cultural or technological) paradigm, presumably driven by some alternative replicator (e.g., memes or temes), and potentially resulting in the extinction, obsolescence, or trophic reorganization of the former. Researchers anticipating a postbiological universe tend to describe this transition as marked by the maturation and potential convergence of high technologies, such as artificial intelligence or nanotechnology.
The dictionary definition of Evolution is any process of formation, growth or development. In biological evolution the main principle behind this development is survival, we evolved to become stronger and quicker, we also evolved to become intelligent. But as we became intelligent biological evolution subsided to a new concept, cultural evolution. Cultural evolution moves at a much faster rate than biological evolution and this is one reason why it isn't very well understood. But as survival is still the main driving force behind life and that intelligence and knowledge is currently the most important factor for that survival, we can reasonably assume that cultural evolution will progress in the direction of furthering intelligence and knowledge.
Cultural evolution progressing in this way and being based upon the furthering of intelligence is known as the Intelligence Principle; this was suggested by Dr Steven J Dick.
"The maintenance, improvement and perpetuation of knowledge and intelligence is the central driving force of cultural evolution, and that to the extent intelligence can be improved, it will be improved" (Dick 1996)
If cultural evolution progresses in this direction then due to cultural evolution being much faster than biological, the limiting factor becomes our biology and the capability of our brains. Currently the closest and so most probable solution to this problem is artificial intelligence, (AI). Experts in AI even believe it holds the potential and capability for a postbiological earth in the next several generations, (Moravec 1988, 1999). AI could be utilised to solve scientific problems and to analyse situations much faster and more accurately than our own minds.
The move to a complete postbiological stage has two different routes. One route is the change of human consciousness from a biological vessel into a mechanical; this would require the digitisation of human consciousness. A mechanical based vessel would increase the computational power and intelligence of the human consciousness exponentially, and also eliminate the weakness of a biological form. This route is therefore a logical progression through cultural evolution with survival and the pursuit of knowledge and intelligence at its centre.
The first route requires a high level of technology, therefore would take a long time, this results in another possible road to a completely postbiological civilisation (PBC). The other route is the complete replacement of human consciousness by AI, for this the human race would co-exist peacefully with our own creation of AI which is scientific, objective, and free from selfish human nature.
The future of the human race through cultural evolution is not known and the possible postbiological outcomes are infinite, so to address what we could evolve into is almost futile. But Hans Moravec predicted that;
"What awaits us is not oblivion but rather a future which, from our present vantage point, is best described as 'postbiological' or even 'supernatural'. It is a world swept away by the tide of cultural change, usurped by its own artificial progeny"
The possible forms a PBC may take are as diverse as in biological evolution, if not more. But from our knowledge of technology and with the intelligence principle being the main driving force we may make some predictions.
The current major limitations imposed upon computation are limited storage space, processing power, dust gathering chips, inefficiency of their human operators and heat dispersion. The only one that is fundamental and fixed is heat dispersion because this is due to the laws of physics. In computation the greater the amount of information to be calculated, (I) the greater the energy needed (E), but the energy needed is also proportional to another factor, the temperature, (T).
Where K is a constant. Therefore, the greater the temperature the greater the energy needed, and so the greater the inefficiency is also. If we now apply the Intelligence principle to this then a PBC would move to decrease the temperature and so increase the efficiency and computational power. In the universe the greatest source of heat transfer is via radiation, therefore a PBC would look to migrate to an area of low radiation and so low temperature. If we now observe the galaxy we see that the most radiation is generated by the galactic centre by both the high stellar density and also highly energetic events such as supernova. Therefore, the coldest regions are away from the galactic centre or inside giant molecular clouds. Giant molecular clouds although being very low in temperature (T~10K) are areas of giant star formation and so the temperature in one location is irregular, which would make it unsuitable for a PBC.
Another factor affecting a PBC would be the abundance of metals and heavier elements needed for expansion and repair. The highest concentration of these elements is found near the galactic centre, where they are created by massive stars. But to a PBC with advanced technology the production of metals via stellar nucleosynthesis in stars is highly inefficient, converting only a small amount of hydrogen to heavier nuclei and the high loss of energy that is produced in the nuclear fusion. Therefore, a PBC would most likely have the capability to produce heavier nuclei through controlled fusion and minimise the energy lost.
By taking the two factors of heat dispersion and heavy nuclei into account we can find a "galactic technological zone" (GTZ), similar to the principle of a "galactic habitable zone" (GHZ) for biological life. Where temperatures are low enough to maximise computing efficiency but there is also matter available for fusion, this most likely lies on the outskirts of the galaxy.
A migration hypothesis exists that takes the GTZ into account. A PBC would most likely not think on a similar time scale to us, therefore although a migration to GTZ may seem inefficient and lengthy to us, a PBC could consider this on timescales of 10^6 years, where the increased computing efficiency received far outweighs the energy required in transportation. The idea of interstellar migrations already exists in literature, (e.g. Badescu and Cathcart 2000).
In the search for extraterrestrial intelligence (SETI) the main focus is on biological life. But the timescale of intelligent biological life could be very short; already some experts believe that we could see a postbiological earth in the next few generations. According to Steven J. Dick, for a PBC to arise other than our own and be present, we must make five assumptions:
We know that assumptions 1, 3, 4, and 5 can take place as we have observed or are observing them on the Earth. For assumption 2 we must consider the L term of the Drake equation, and the timescale over which intelligent biological life can form. Around 1 Billion years after the start of the universe the first sun-like star had formed, and there were enough heavy elements around for planet formation (1998, Larson and Bromm 2001). From the earth we know that intelligent life can form within 5 billion years, this puts a lower time scale on which intelligent life can form, 6 billion years. And from the current rate of technological progression the leap from intelligent life to a PBC is negligible compared to the astronomical timescale. This means we could already be looking at a postbiological universe. In our own galaxy the first sun-like stars formed at around 4 billion years therefore we could already have a PBC in our galaxy that formed 3-4 billion years ago.
If we consider this possibility of a PBC in our galaxy we are still faced with Fermi's paradox. However many of the proposed solutions for Fermi's paradox also hold true for a PBC. In terms of the search for extraterrestrial life and astrobiology because of the almost infinite possible forms a PBC could take and our lack of understanding of these we would effectively be blind in this search. For this reason even though there is a logical argument for the existence of PBCs our best hopes remain with looking for biological life.
While in some circles the expression "postbiological evolution" is roughly synonymous with human genetic engineering, it is used most often to refer to the general application of the convergence of nanotechnology, biotechnology, information technology, and cognitive science (NBIC) to improve human performance.
Since the 1990s, several academics (such as some of the fellows of the Institute for Ethics and Emerging Technologies) have risen to become cogent advocates of the case for human enhancement while other academics (such as the members of President Bush's Council on Bioethics) have become its most outspoken critics.
Advocacy of the case for human enhancement is increasingly becoming synonymous with "transhumanism", a controversial ideology and movement which has emerged to support the recognition and protection of the right of citizens to either maintain or modify their own minds and bodies; so as to guarantee them the freedom of choice and informed consent of using human enhancement technologies on themselves and their children.
Neuromarketing consultant Zack Lynch argues that neurotechnologies will have a more immediate effect on society than gene therapy and will face less resistance as a pathway of radical human enhancement. He also argues that the concept of "enablement" needs to be added to the debate over "therapy" versus "enhancement".
Many critics argue that "human enhancement" is a loaded term which has eugenic overtones because it may imply the improvement of human hereditary traits to attain a universally accepted norm of biological fitness (at the possible expense of human biodiversity and neurodiversity), and therefore can evoke negative reactions far beyond the specific meaning of the term. Furthermore, they conclude that enhancements which are self-evidently good, like "fewer diseases", are more the exception than the norm and even these may involve ethical tradeoffs, as the controversy about ADHD arguably demonstrates.
However, the most common criticism of human enhancement is that it is or will often be practiced with a reckless and selfish short-term perspective that is ignorant of the long-term consequences on individuals and the rest of society, such as the fear that some enhancements will create unfair physical or mental advantages to those who can and will use them, or unequal access to such enhancements can and will further the gulf between the "haves" and "have-nots".
Accordingly, some advocates, who want to use more neutral language, and advance the public interest in so-called "human enhancement technologies", prefer the term "enablement" over "enhancement"; defend and promote rigorous, independent safety testing of enabling technologies; as well as affordable, universal access to these technologies.