Published in the December 2019/January 2020 issue of Philosophy Now
A little-known magazine, Bioastronomic News, published, in one of its 1995 issues, a memorable debate between two famous scientists. The echo of the debate still reverberates in the texts from the New York Times, to modern scientific journals and books. On one side of the argument was a celebrated astrophysicist, Carl Sagan (1934-1996). On the other side was a respected biologist, Ernst Mayr (1904-2005). The topic of the debate was the validity of the research programme known as the Search for Extraterrestrial Intelligence or SETI.
Sagan eloquently argued that the unimaginable vastness of cosmos must contain civilizations that, similarly to ours, discovered electromagnetic waves. According to Sagan, life on the cosmic scale rewards smartness. By using radio telescopes, and with a bit of luck, we may be able to register the technological traces of distant civilizations with which we share that convergent quality known as intelligence. A long-anticipated cosmic rendezvous, the stuff of the Hollywood and science fiction dreams, may come to fruition one day.
Mayr, on the other hand, expressed deep doubts about the chances of SETI. His basic argument was that the intelligence of the human type is extremely rare on the evolutionary scale. So rare, that the existence of two human-type civilizations sharing the cosmic coordinates of space and time from which they can reach each other, is negligible. From the evolutionary perspective, in which success is measured by the length of survival, it is more advantageous to be stupid than to be smart. Bacteria, in our perception stupid organisms, survive all possible planetary catastrophes. On the other hand, the smartness of the human type is an obstacle to evolutionary longevity. Bigger brains mean more sophisticated tools and technologies. Sophisticated technologies generate existential risks, as we know from our own experience.
The theme of this essay is not SETI but intelligence on the evolutionary scale. The debate between Sagan and Mayr is a good introduction because it captures nicely two approaches to the problem of intelligence, the anthropocentric Sagan’s approach, and the biocentric Mayr’s approach. The two approaches, on their own, are incomplete. Only when combined into one complementary approach can they be useful in the interpretation of intelligence as an evolutionary phenomenon. The product of this complementarity is a metaphor I have called the astrobiological cat. It stems from the proverb When the cat’s away, the mice will play. Let’s find out who’s the cosmic cat and who are the mice.
Anthropocentric intelligence
According to Ray Kurzweil, a leading futurist, explanations behind human intelligence will always be controversial. The least controversial way of defining intelligence is through the analysis of the components that make it up: learning, reasoning and the ability to manipulate symbols. Learning is a process of acquiring knowledge. The reasoning is the ability to make valid conclusions based on acquired knowledge. The ability to learn and reason is possible because we have the ability to manipulate symbols. This ability is the heart of language and mathematics.
Another way of defining intelligence is related to its purpose. What’s the purpose of our ability to manipulate symbols? A simple answer, according to Kurzweil, is that intelligence serves the owner to develop strategies for achieving and improving her goals. In the biological world, goals are defined as the ability of individual organisms, or biological species, to survive. It is not yet possible to know with certainty whether intelligence serves to increase evolutionary fitness. But, with a small dose of bias, it is possible to conclude that our intelligence serves to help us achieve set goals such as economic, social or scientific success.
Kurzweil then goes on to suggest that the peak of human intelligence is the ability to create intelligent machines. As we know from modern AI research, machine intelligence constantly advances. By contrast, human intelligence remains the same. From this relationship, Kurzweil concludes that if the advancement of machine intelligence continues, machines will overcome human intelligence in the near future and become a superior form of life. In the AI circles, this is known as the technological singularity or intelligence explosion.
In order to justify the possibility that the creator of AI, that is, Homo sapiens, is not inherently superior to his creation, the intelligent machines, Kurzweil uses an example of the relationship between evolution and Homo sapiens. Evolution itself is an intelligent process that creates new organic forms. The peak of evolutionary creativity is Homo sapiens. We are a species that, according to Kurzweil, surpassed the evolution. While evolution took 3.8 billion years to create us, the most intelligent species in the history of life, we need incomparably less time to create intelligent machines, a product that will surpass the greatest achievement of evolution, ourselves. Kurzweil goes further and predicts that machines will turn planet Earth into a gigantic computer by the year 2099. This will open the door for the computerization of the cosmos.
Biocentric intelligence
Modern biology is under a heavy influence of neo-Darwinism – a combination of Darwin’s theory of evolution by natural selection and genetics. For neo-Darwinian biology, popularized amongst others by Ernst Mayr, evolution is a blind and mindless process. Any hint of intelligence looks suspiciously teleological.
The standard neo-Darwinian narrative goes like this. Genes or their assemblies called genotypes, or genomes in modern terminology, produce organic forms or phenotypes: bacteria, plants, giraffes, humans. The natural environment then selects the organic forms that are best adapted to it. Adaptability is measured by the concept of fitness – the number of descendants produced by any organic form. The mechanism behind adaptability is the change in genes – gene mutations – that fine-tune the phenotypes and give them evolutionary longevity. Evolution is thus a blind game between genes and the natural environment. Phenotypes, or organisms, are passive and dumb puppets, or “lumbering robots” in the words of Richard Dawkins, controlled by these two powerful evolutionary forces.
However, neo-Darwinism is not universally accepted. The first scientist, who successfully rebelled against it, was Lynn Margulis (1938-2011). She was famous for popularising the concept of symbiogenesis. Biological innovations do not have to be the result of gene mutations. They can happen by merging two or more microbes into one – the process known as symbiosis, or living together – from which all plants and animals descended.
Margulis’ struggle against neo-Darwinism, celebrated in a recent documentary, SYMBIOTIC EARTH, How Lynn Margulis Rocked the Boat and Started a Scientific Revolution, encouraged the growing number of biologists and philosophers of biology to think outside the box and analyze intelligence on the evolutionary scale. Contrary to neo-Darwinian views, intelligence seems to be a biological universal. Organisms, from bacteria to elephants, are not passive “lumbering robots”, but instead they are active learners or “knowers”, who actively construct their environments. Recent scientific papers are replete with the terminology which suggests that (i) organisms are cognitive agents and (ii) evolution is a cognitive process. Here are some relevant terms: “bacterial IQ”, “bacterial cognitive tool-kit”, “plant intelligence”, “bacterial linguistics”, “language of the bees”, “plant language”, “bacterial internet”, “zoo-pharmacognosis”, “honeybee democracy”, “ant agriculture” etc.
Synthesis
The emerging branch of biology – known as the systems view of life – which interprets intelligence as an integral part of the process of life, opens a new possibility that I call biological civilizations or bio-civilizations. The concept of bio-civilizations is simple. Each biological species intelligently creates its own surrounding world, an equivalent of a species-specific civilization, by actively constructing its environment. For example, bacteria turned the dead planet into the living world. This amazing transformation required natural skills such as communication (bacterial language), construction (e.g. oxygenation of the atmosphere) and computation (e.g. natural calculation behind the cycles of organic elements, such as carbon, controlled by bacteria). The bacterial civilization has become the basis for the entire biosphere, which was gradually enriched by millions of new species and their civilizations emerging from the bacterial world. We can view the biosphere as a form of the biological multiverse comprised of individual bio-universes, or bio-civilizations. Understood this way, the concept of bio-civilizations is a great challenge to Sagan’s and Mayr’s visions of intelligence. Here is a short narrative that reveals the origins and development of bio-civilizations.
One ordinary cosmic thermodynamic factory, a star called the Sun, found its first biological partner, photosynthetic bacteria or cyanobacteria, in the microcosmos of a minor planet called Earth, roughly three billion years ago. To use a more poetic language, cosmos, through a star which can accommodate 1.3 million Earths, “appointed” its micro-representative to be the first cosmic “ambassador”, or perhaps its “spy”, on the planet Earth. In the entire history of cosmic observations, there is no better partnership between the macrocosmos and the microcosmos, than the Sun – cyanobacteria partnership. The result is photosynthesis, a process that to this day fuels life on Earth.
Over time, the partnership Sun – cyanobacteria, which produced all plants and animals including us, became a complex biological system called the biosphere. This system is an open thermodynamic system. It constantly exchanges matter, energy, and information with its cosmic surrounding and spontaneously maintains its balance. Life was born within the earthly dead matter, on the waves of the Sun’s thermodynamic storm. We are riders on these waves, like Riders on the Storm of Jim Morrison and Doors:
Riders on the storm
Into this house, we’re born
Into this world, we’re thrown
Like a dog without a bone
An actor out alone…
We are temporary and fragile surfers on the thermodynamic storm of life. While surfing, we are discovering the world. The sea that produces waves for our surfing is the “bacterial sea”. Bacteria are the basis of the biosphere. Lynn Margulis understood this better than anyone else when she helped James Lovelock explain how bacteria maintain the stability of the biosphere or its homeostasis.
A new interpretation of intelligence
The above narrative reveals several new qualities associated with biological intelligence. First, bacteria are an intelligent cosmic “player” because they detect cosmic electromagnetic waves. This means that elements of SETI exist independently of us. The idea behind SETI is to send electromagnetic waves, in the form of radio waves, deep into the cosmos and wait with the hope that a resonant structure, a hypothetical extra-terrestrial civilization, will respond to them. Bacteria detect a part of the electromagnetic spectrum we call visible light, with a range of 400-700 nm (nanometers). Bacteria then transform the light energy into useful work, which in the long evolutionary process created the biosphere. The biosphere is nothing but a giant bacterial superorganism that envelops the planet and goes deep into its surface. We can best imagine it as an invisible planetary cloud.
A microbiologist Sorin Sonea (1920-2017) suggested that the bacterial planetary cloud is intelligent because it possesses the inner mind. The manifestation of the bacterial mind is the information network in the form of the planetary free market for bacterial genes. If there is a bacterium anywhere on the planet Earth, in search of a specific gene, it will quickly find it and acquire it in the complex process of genetic exchange.
Similarly, Eshel Ben-Jacob (1962-2015), physicist and microbiologist, thought that the bacterial planetary superorganism not only possess the natural mind, but it also carries out the acts of natural computation that are at the core of the biosphere’s homeostasis (biogeochemical cycles of organic elements). Finally, a leading microbiologist, James Shapiro, believes that bacteria are more sophisticated than humans “in controlling complex operations.”
A second important novelty is the strangeness of the bacterial universe. In our universe, we are the most intelligent species. But, when we peek into the bacterial universe, we become insignificant. In the bacterial universe, according to some philosophers of biology, all large organisms, such as plants and animals, become “macrobes” trapped into the microbial, that is bacterial, network. Macrobes are bacterial chimeras. For example, photosynthesis is still carried out by bacteria, which are now endosymbiotic parts of macrobes we call plants. Microbes manipulate all macrobes including us. All macrobes have their microbiomes without which they cannot survive. When a bird is flying, its microbiome is in the sky too. When we fly into the cosmos, our bacteria travel with us. All macrobes, including us, are bacterial vectors. If we embark on the cosmic travel and create human cosmic settlements on distant planets, bacteria will be their part as well. If we fail in the cosmic conquest, bacteria will continue our mission – bacteria can survive any new cosmic environment unlike us.
The good news is that the two universes, human and bacterial, are not mutually exclusive. The bio-civilization is a kind of multiverse, a collage of biological worlds that depend on one another. Jakob von Uexküll (1864-1944) elaborated this idea first, through the concept of Umwelt – a species-specific surrounding world. Today, his idea is at the heart of a new discipline called biosemiotics.
The third novelty is the poverty of neo-Darwinism when it comes to interpreting intelligence. Ernst Mayr’s claim that it is better to be stupid than to be smart on the evolutionary scale, is false. This betrays the rigid neo-Darwinian treatment of microbes: bacteria are lower organisms than plants and animals, and thus the most primitive forms of life. As we have seen, many biologists who do not follow the neo-Darwinian narrative consider bacteria intelligent. They clearly disagree with Mayr. If there is stupidity on the planet Earth, it is certainly not associated with bacteria.
The fourth novelty is the fallacy of the view that Homo sapiens is at the top of evolutionary intelligence, and that it has surpassed evolution. Ray Kurzweil’s prediction that the planet Earth will become a gigantic computer by the year 2099 is problematic in light of the fact that natural computation on the planetary scale exists for billions of years in the form of bacterial regulation of biogeochemical cycles of carbon, nitrogen and other organic elements.
Cosmic zoology
Finally, we can focus on the astrobiological cat metaphor. Bacteria, or more precisely their planetary superorganism, are the dominant biogenic factor on the cosmic scale – a biogenic structure that silently looms over the planet. Bacteria exist 3.8 billion years, which is roughly one/quarter to one/third of the duration of cosmos. Yet Sagan’s vision of intelligence glorifies the human equivalent regardless of its insignificance on the temporal scale and the fact that bacteria can “read” a portion of the electromagnetic spectrum. Mayr’s vision, on the other hand, denies any hint of intelligence to bacteria and it reserves it exclusively to one organism – Homo sapiens.
Here is the explanation of the metaphor. The bacterial superorganism is invisible to us, and yet in control of the planetary life since its inception, 3.8 billion years ago. This invisibility gives us a false sense that we humans are the masters, irrespective whether we take for granted Sagan’s or Mayr’s narrative of human dominance over all other forms of life. To a biologist like me, influenced by the systems view of life, this situation is irresistibly reminiscent of the old proverb When the cat’s away, the mice will play. With one important difference – the cat is not absent but invisible. Hence, the astrobiological cat – the invisible planetary cloud of bacteria controlling, with its own inner mind, the planetary life for billions of years. The control is benign enough to allow all sorts of proverbial mice.
If we accept the metaphor, the key question is this. Why is the astrobiological cat so unnoticeable that its false absence allows the proverbial mice a disproportional projection of their own importance? I strongly believe that neo-Darwinian biology, which traditionally focuses on macrobes (in particular animals) and almost completely ignores microbes, is to blame for this form of epistemic blindness. The mainstream neo-Darwinian biology has become too narrow for fundamental topics such as biological intelligence, or the application of this topic to programmes such as SETI.
The metaphor must also have some practical applications. If it remains only within the limits of the critique of neo-Darwinian biology, it will quickly go to dust. I see two research avenues originating from the metaphor. The first one is related to the bacterial superorganism, the microbial cloud that contains its own mind I called the bacterial Internet. Estimates show that the total number of bacteria that form the cloud is 1030. However, bacteria are not the most abundant microbes on Earth. The most numerous biogenic structures on Earth are viruses. For each bacterium, there are at least 10 viruses. What’s the role of viruses in the planetary microbial network? The only useful clue, for now, is the idea of the planetary free market of genes. Its function is to enable the bacterial superorganism to perform all the necessary biological processes involved in biogeochemistry. Viruses are pieces of inert genetic information protected by a biological membrane. Like a message in a bottle floating through the bacterial sea, until it finds the appropriate bacterial user and helps it in the search for biological innovation. The astrobiological cat must solve its own viral mystery.
The other avenue is related to the SETI program. My suggestion is that a new segment should be incorporated into SETI: how life as an intelligent biogenic process can spread into cosmos, without being overburdened with the anthropocentric bias. We, as bacterial vectors, undoubtedly play an important role in this process. The two universes, bacterial and human, are not mutually exclusive. Together, they form a complementary multiverse useful for both species. Scientists have shown that the international space station is contaminated with bacteria from our microbiome. Attempts to decontaminate the station will surely remain unsuccessful. Instead of looking at bacteria as an enemy, SETI should accept biological reality.
Bacteria will almost certainly outlive us, as Lynn Margulis argued in her book Symbiotic Planet. Macrobes like us are transient biological forms. Temporary structures that disappear with the evolutionary wind like ordinary dust. Contrary to our anthropocentric bias, only bacteria live forever! The best evidence for this claim is the fact that bacteria are as old as life itself – 3.8 billion years.
