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Failure Interviews

Where there’s perfection there’s no evolution

Natural history is a catalogue of imperfections and reality adjustments

Interview with Telmo Pievani

Biological Sciences Philosopher University of Padua

By October 2020April 26th, 2022No Comments
Photo by Lorenzo De Simone

Guido Tonelli’s new book on the genesis of the cosmos is titled “The imperfect birth of things”. Are we then the product of an imperfection, of a casual mistake?

Tonelli attempts to present the history of the cosmos with an extraordinary evolutionary approach. In his book he discusses how the Universe was born from a process, which was not solely guided by the laws of physics but also by a small primordial asymmetry in the quantum vacuum, an event that could not be foreseen beforehand and that derailed the road of the evolution of the cosmos towards an unexpected direction. That does not mean that our existence is random and that it’s all up to chance. There are the laws of physics and they are very important, just like the regularities of the evolution process. However, they are not so powerful that they make the process deterministic- prearranged since the beginning and set on a single possible path. In fact there are also contingencies. In a series of letters addressed to his American colleague, Charles Darwin wrote about being worried to discover how much was determined and how much was casual in evolution just to end up concluding that it was all a matter of laws and chance, a dialectic between regulatory elements and casual idiosyncratic ones. On some occasions the regulatory aspects prevail and in those cases the process is more or less directed; other times instead the casual aspects prevail and they lead to a change of direction, they are a turning point. Everything we’ve learned over the century and a half that followed confirmed Darwin’s intuition. Today we can state that biologic evolution, just like the evolution of the cosmos, have an element of contingency and that we are the product of those turning points, those small imperfections.

Why is imperfection so ever-present in nature?

Often when we discuss biologic evolution everyone knows that there is imperfection and that there are suboptimal structures. The canonical interpretation, valid till not long ago, usually considered imperfection a mistake, a bump in the road, just like a cake that has all the right ingredients but for some reason does not rise as it should, or like the ingredients of the mayonnaise that stay separated. In reality things are not actually this way. Imperfection is intrinsic to the evolutionary process and it is a good thing that it is there. It is exactly what we should expect if evolution works the way we know- through various casual genetic variations and selective processes. Moreover it should be understood that natural selection couldn’t start from zero each time. There couldn’t be an ad hoc adaptation for each environmental change, as this would require too much time and energy. Therefore what does nature do? It looks for a quicker and more economical way, because otherwise the alternative would be extinction. Therefore it begins from what is already there, it reuses the available material, modifying it and transforming it so it can have new functions. It makes virtues out of necessities. Given the situation the outcome won’t be perfect but it will be the best possible one. This is the reason we are so imperfect but also so creative and powerful.

Paradoxically, as you describe in your book “Imperfection”, the brain and the genome- two of the most complex systems- are also “clearly imperfect”. You define them as “unnecessarily complicated, corrections, supplements and compensations”.

As a great biologist wrote on Nature, we are an encyclopaedia of imperfections, a compendium of imperfections. We are that, starting from DNA, even the human one, which is a formidable biochemical machinery, one of the greatest inventions of evolution. The nucleus of each of the 100,000 billion cells that form the human body contains an incredible amount- a quantity that even the most powerful microchip cannot reach- of encoded genetic information in the DNA for the synthesis of all the proteins necessary to the life of the organisms. Nevertheless, for different reasons even the double helix is not so perfect and omnipotent. Sometimes the sophisticated reaction chain that consents the passage from the sequence of nucleotides to the assemblage of amino acids in proteins can get stuck. In this case it is a simple and casual structural incident. If we then look at the informational part of our DNA- everything starts from here- we discover that it only contains 22 thousand encoding genes, no more than 2 per cent of the nucleotide sequences that compose it. Moreover there are great redundancy, multiple repeated sequences and viral sequences that were inserted by the retroviruses that we survived in the past. Basically, as someone put it, it is a jungle. As an evolutionist I would add that it is lucky because this is what enabled the system to evolve: the great amount of so-called “trash” DNA has its own function, which is useful for the continuity of life. The DNA would not have had the same potential to modify itself and evolve if it had been a specialised and perfect machine since the beginning.

That is the case also because, as you wrote, perfection is paradoxical and as such it cannot be perfectible. Without imperfection does nothing happen, doesn’t progress take place?

The notion of imperfection is one of the different modalities in which we can question the persuasive progress metaphor that has always been typical of evolution studies. After Darwin we learned that the great majority of biodiversity is made up of rather simple unicellular organisms that are very effective. An example is the sars-cov-2 virus, an organism formed by a single filament of RNA enclosed in a capsule of proteins that keeps extremely complex organisms in check. The evolutionary process is not a sort of filigree that must lead to increasingly more complex organisms, thus necessarily to Homo sapiens. We are simply one of the possible outcomes of evolution and beyond us there are many other ones with much lower degrees of complexity. Progress can only be measured in retrospect: who knows whether in a million years from now Earth will be full of viruses and bacteria or the descendants of human beings.

In “Faust” Johann Wolfgang von Goethe exclaimed, “Stop, moment, you are beautiful”, as a way to make a perfect moment last forever. Is it imperfection that makes us perceive the sense of time and evolution then?

Imperfection makes us appreciate the sense of time flowing but not the moment, as the beautiful Goethean quote expressed. This is also the case for evolution. If we studied natural history looking at individual moments we would not get an outlook on what happened but only a snapshot of a process that happens in that precise moment and we could only observe the proximal causes. If, for example, we took a snapshot of the eye mechanisms, we would be led to think that it was perfect and complete. However, it’s imperfection that allows us to see the flux, or what lies behind what you see. This is why Darwin used to say that in order to understand evolution one should look, for example, at rudimentary organs such as the intestinal appendix or the wisdom teeth of men, or the atrophied wings of penguins. These are organs that lost their utility but tell us about the past state of things: for example in the past the penguin used its wings to fly and following environmental and behavioural changes, they were dismissed so what is left of them is just rudiments. Darwin wrote, “They could be compared to the letters of a word that are present in the spelling but are not pronounced; they nonetheless guide us in the search for its etymology”. Everything in nature is part of a process that is continuously changing. This is the reason why in biology it is very challenging to find a criterion to define an entity as inconspicuous with some boundaries, because everything is transforming, starting from the species itself.

In the last pages of the book you wrote that imperfection, apart from being an irrefutable evolutionary feature, is the awareness of and the management of our fragile human limits, first of all the transience and poor farsightedness. Could you explain that?

What is typical of natural evolution is ambiguous, ambivalent and amoral. Imperfection is natural, but that does not mean that being imperfect is fair and pleasant. Imperfection also means pain and discomfort. The bottom line is that nowadays an imperfect species like us, aware of it but still being so, has an unprecedented power of intervention on nature and on itself. Trivially, whenever an imperfect species is very powerful there are higher chances of it utilising these instruments in an unwise manner, even suicidal. Therefore the ethical warning is about reflecting on our imperfection because we are guests and not owners in this world. The pandemic demonstrated how vulnerable we are, and especially how much we should fear an evolutionary enemy that is much more ancient and simpler than us- and even more perfect in Darwinian terms, given it is a machine programmed to do one individual thing well: replicating itself and utilising us as a vector to spread. Furthermore, the pandemic showed how closely connected and dependent we are to the ecosystems we are immersed in, which is something we deluded ourselves to think we could overcome and forget. One of our great limits is not having farsightedness: our brain is imperfect; some of its archaic parts make us take quick and instinctive decisions that are vital in some occasions but that push us towards a teleological thought. This is linked to the here and now and makes us commit ethically only to what is proximal to us in time and space. Instead, whenever we are asked to commit to outcomes that will project to a far time, we struggle. Today this is an issue because we are faced with challenges that require a lot of farsightedness.

What is typical of natural evolution is ambiguous, ambivalent and amoral. Imperfection is natural, but that does not mean that being imperfect is fair and pleasant.

Stephen Jay Gould said that if we could rewind the biologic evolution movie and show it again, it is unlikely that Homo sapiens would appear at the end of the screening. If we fast-forwarded it and took a look at the future what should we expect at the end of the movie? Where is our natural and human imperfection taking us?

The example of the movie of life is exactly the practice of contingency. A contingent process is an intrinsically unpredictable process whose casual factors and the laws of the system interact with one another. Gould considered evolution a contingent process and used to say that by repeating for the nth time an evolution process we would never get the same result each time. If we had to rewind the biological evolution movie we would find life forms that are similar to ours under many aspects- for example bacteria- but that are still a bit different. We will verify this once we will find alien life forms. This is also the case for human evolution: it is quite improbable that there will be another Homo sapiens appearing again. In the same way, if we could fast-forward the movie of life we should expect that other contingent events might lead the future towards unexpected directions. Our future is open, as Karl Popper used to reiterate, it is not all written in the past or in the present. However, as Homo sapiens, we can intentionally choose a direction, for example following a direction towards environmental sustainability or environmental destruction, and we can influence the events to favour a more desirable counter-future. Evolutionists are not allowed to make medium and long-term predictions, but I am sceptical around how many say that there will be a post-human species and a new human species. I believe that in thousands of years from now Homo sapiens will still be there, maybe a 2.0 version, but we will still be human beings and we will be the ones who will have impacted more and more on our own evolution. The great gamble is how wise we will be when utilising technologies for ethically and socially beneficial purposes. Therefore in the future everything will depend on our mental choices, which will have to be ethically motivated, with a great question mark around unpredictability, as the evolutionary process of science and technology is intrinsically serendipitous. In the same way as we could never have foreseen the arrival of the web in the sixties, today, in 2020, we should be aware that we absolutely cannot predict what inventions will be created in half a century. The reason for this is that in science what is discovered often is not what was being sought in the first place.

Edited by Laura Tonon