Deep-time self-identity can help in dealing with nuclear disarmament. Including one’s DNA information as part of one’s self-identity extends one’s life line into the deep time of evolution. Genomics has shown that all persons on our planet belong to one family as far as DNA is concerned. A genomic perspective extends our self-identity to about 500 000 years ago as homo sapiens, and it reduces the relative importance of traditional social categories based on political borders and languages. Deep-time self-identity is a broadly unifying concept. Once widely accepted it will sharpen the incentives for all humankind to cooperate in eliminating nuclear weapons and in dealing with the challenges of international security, climate and species preservation, pollution and overpopulation.
Birth of genomics
Genomics expands the older discipline of genetics and has the ambitious goal of studying all genetic information in a great many species and over a substantial part of the deep time span of evolution. A turning point occurred in 1953 when Watson and Crick discovered the double helix structure of DNA comprising the molecules adenine, thymine, guanine and cytosine, universally represented by the letters A, T, G and C, respectively. Numerous discoveries were made in genetics giving rise to several Nobel Prizes and opening the path to reading out, or ”sequencing”, the entire set of three billion letters in the DNA of our biological cells.
Fig 1: A person’s DNA is partly pictured in her/his head, even though in actual fact it is everywhere in the body. At shoulder height are shown DNA strands inherited from the person’s parents. A person gets half his/her DNA from the mother, and half from the father. In this example, this person’s conception occurred 25 years ago. If we look at the grandparents DNA (stomach height), the person inherited only one quarter from each, at a time chosen as 50 years ago in this example. The key concept consists in seeing part of oneself, namely DNA information, as traveling in time by leaping (DNA replication events) through inter-generation time gaps, 25-year gaps in the example chosen here. The legs are here pictured as hosting DNA strands from the great-grandparents. One eighth of 20 000 genes is 2500 genes, which is a lot.
In March 1989 Time Magazine announced the birth of the international Human Genome Project (HPG) whose mission was to develop hardware and software techniques to sequence our DNA within one decade (ref. 1). Leon Jaroff’s article was illustrated by the drawing of a baby schematically showing a portion of its DNA. Fig. 1 in the present article illustrates the fact that one’s DNA information has traveled over time through the generations of parents, grandparents, etc … The picture of self-identity in Fig. 1 tremendously enlarges this concept along the temporal dimension, the full extent of which is approximated by the mathematical symbol of infinity in the feet.
DNA as a reliable historian
DNA as historian is an important consequence of the birth of genomics which has been clearly expressed in the titles of the books in references 2 and 4 and in the contents of the other books (refs. 2-8), published since 2000. Focusing first on Matt Ridley’s fascinating 2000 book, the reader is invited by the title to look at our human genome as a historian and as a memory. Matt Ridley has made the important point that DNA information can be laid out along a line, that is a single mathematical dimension, whereas our body is constructed during embryological development in a three-dimensional frame. One can therefore regard our body as the result of a mathematical transformation of linear DNA information into a three-dimensional frame. Adding the fourth deep-time dimension, as advocated here, transforms each one of us into a four-dimensional being, a concept familiar to physicists thanks to Albert Einstein’s and Herman Minkowski’s work in special relativity.
Genomics has shown that DNA is a reliable historian. This vital property arises from the fact that DNA replicates itself with an extremely low error rate, that being approximately one single-letter mutation per 100 million letters per cell division. In going from the parents’ generation to the children’s one, a small number of cell divisions take place along with DNA replications, with the result that there are about 100 single-letter mutations per generation (ref. 2). Since only about two percent of our DNA codes for proteins, on average only two significant single-letter mutations are passed on from one human generation to the next. Considering that the three billion letters represent the number of letters in about 5000 books of 500 pages, we can rightfully be impressed by the extremely high accuracy of DNA replication.
DNA information as part of our self-identity
Our genome has often been described as a set of instructions to build a human body and to operate it at the biological level. A striking view of DNA is that expressed in Spencer Wells’s book on page 68 of chapter 3 (ref. 3). In the first part of this chapter Wells described mitochondrial DNA (mtDNA), which comprises 16 569 letters hosted in each mitochondrion organelle in our biological cells. Talking about his grandmother Margaret, Spencer wrote:
”While Margaret died in 1996, my mother and I carry her mtDNA with us — a small piece of Margaret that lives on inside us today.”
Philosophers allow themselves much freedom in their choice of principles and hypotheses. In the spirit of the quotations above, we can take as alive, and as part of our self-identity, DNA information that has traveled from our ancestors to us and resides in our bodies. In the conventional view of a person’s self-identity the time line typically extends over one hundred years or less. If you identify with homo sapiens your deep-time self-identity expands its time line to approximately 500 000 years ago. If you choose to identify with life, then your time line extends out to the deeper three billion years ago.
Genetic markers as elements of ancestral lineage
Once a person’s self-identity is taken to comprise DNA information that has traveled through long stretches of deep-time, what can we say about it? That is essentially the difficult question addressed by refs. 2-8. I will say here just a few words about genetic markers. A marker is a mutation (DNA replication error) that has taken place in one individual at one point in time and at one locus in the human genome. The simplest and most useful example is a base substitution, let’s say as an example a change of an A (adenine) to a G (guanine) at one locus in the Y chromosome of a man. Since the error rate in replicating a DNA letter is only once per 100 million replications, this letter G is not about to be changed for a long time and it will stay as such for possibly millions of years through successive generations.
As deep-time has unfolded more mutations have occurred giving rise to more and more markers. Genomics scientists have developed ways of reconstructing partially the deep-time history of our DNA. The one important point I want to make here is that every individual on our planet has an individual genome comprising markers that identify her/him and that have come from the depths of time. Because of Darwin’s natural selection principle we know that to a great extent the markers we now have correspond to improvements that have accumulated in our DNA.
Adam Rutherford has explained that around 1400 years BC almost all of us now living on the planet had the same ancestors. A given person today can imagine that in 1400 BC a few million ancestors were carrying fragments of DNA information that she/he now carries. This means that from a genetic information point of view each one of us is made up of the past. A good part of our behavior is innate, or instinctive, which is another way of seeing the action of humankind’s past history in us. Thanks to the digital nature of DNA information and thanks to its reliable replication, each one of us can look at herself/himself as a representative of humanity and its 500 000-year homo sapiens history on equal footing with others. In this perspective does it make sense to let the threat of nuclear war persist?
Nicholas Christakis, Matt Ridley and Elizabeth Zelman
In his 2019 book by Professor Nicholas Christakis of Yale University has put forth a theory according to which the evolution of the human genome over the last million years has made us capable of building good societies (ref. 9). These are societies based on a few traits like the capacity to have and recognize individual identity, love for partners and offspring, friendship, social networks, cooperation, and social learning and teaching. Professor Christakis and his research team have studied many human communities and even groups of social animals like chimpanzees, bonobos, elephants and whales. Their research results present a strong case for believing that genetic evolution with Darwin’s selection principle leads to good societies not only with humans, but with several species of animals. Darwin emphasized competition as the main driver of evolution; many modern authors now think that competition and extensive cooperation are the main drivers of evolution.
Professor Christakis is of course aware of the setbacks caused by many wars in our history, but he presents convincing arguments that we are genetically fashioned to improve our lives. In his preface, Christakis wrote the following paragraph which supports his optimism regarding the future of our societies:
‘’My vision of us as human beings, which lies at the center of this book, holds that people are, and should be, united by our common humanity. And this commonality originates in our common evolution. It is written in our genes. Precisely for this reason, I believe we can achieve a mutual understanding among ourselves.’’
Another author who has looked into genomics is science writer Matt Ridley. His 1996 book is entitled The Origins of Virtue, Human Instincts. On pages 6 and 7 he wrote:
‘’It is the claim of this book that the answer to an old question – how is society possible? – is suddenly at hand, thanks to the insights of evolutionary biology. Society was not invented by reasoning men. It evolved as part of our nature. To understand it we must look inside our brains at the instincts for creating and exploiting social bonds that are there. We must also look at other animals to see how the essentially competitive business of evolution can sometimes give rise to cooperative instincts.’’
Yet another author who has emphasized the importance of empathy and cooperation in order for us to evolve in a positive direction is evolutionary anthropologist Elizabeth Crouch Zelman.
Evolutionary anthropologist Elizabeth Zelman has written an impressive book entitled Our Beleaguered Species, Beyond Tribalism, which is in harmony with authors Christakis and Ridley (Zelman, 2015). What I find especially important in Zelman’s book is the philosophical depth of her discussions. Her book looks in a most inquisitive manner into the nature of the self. The readers will find our kinship to animals underlined, especially to bonobos and chimpanzees, our closest cousins in evolution. We basically possess and are driven by all the emotions that are present in our cousins. But what especially distinguishes us from our animal cousins is our far-reaching empathy and our reasoning power. Unlike our animal cousins, we can develop empathy for all human groups on the planet. Our capacity for empathy and reasoning should also be directed to protect all forms of life.
Changing your self-picture by including your genomic dimension extends your life line to one million years or more, and in spatial extension to all of humanity. If this idea could become viral, that would eventually force the armed services in all countries to look at all ethnic groups as self, and thus eventually render war obsolete. There has been a rapid evolution in the ability of precision-guided conventional weapons so that in principle military targets could be selectively destroyed when need be without injuring civilians. Even soldiers on both sides could have their lives spared if the pro-human rights principles were strictly adhered to. Overall, a genomic approach to life could lead to a far more pleasant world to live in.
-1. Leon Jaroff, ”The Gene Hunt”, Time Magazine, pp. 54-55, 20 March 1989.
-2. Matt Ridley, Genome, the Autobiography of a Species in 23 Chapters, Perennial, 2000.
-3. Spencer Wells, Deep Ancestry, Inside the Genographic Project, National Geographic Society, 2007.
-4. Adam Rutherford, A Brief History of Everyone Who Ever Lived, The Human Story Retold Through Our Genes, Orion Publishing Group Ltd. (2016), The Experiment, LLC (2017).
-5. Bryan Sykes, The Seven Daughters of Eve, W.W. Norton, 2001.
-6. Svante Pääbo, Neanderthal Man, In Search of Lost Genomes, Basic Books, 2014.
-7. Carl Zimmer, She Has Her Mother’s Laugh, the Powers, Perversions, and Potential of Heredity (2018), Dutton, Penguin Random House LLC, New York.
-8. Siddhartha Mukherjee, The Gene, An Intimate History, Scribner, New York, 2016.
-9. Nicholas Christakis, Blueprint, The Evolutionary Origins of a Good Society, Little, Brown Spark, 2019.
-10. Matt Ridley, The Origins of Virtue, Human Instincts and the Evolution of Cooperation, 1994, Penguin Books.
-11. Elizabeth Crouch Zelman, Our Beleaguered Species, Beyond Tribalism, 1915, Library of Congress Control Number 2014918689.
Michel Duguay studied physics at the Université de Montréal and at Yale University, graduating in 1966 with a Ph.D. in nuclear physics. He worked for 21 years at AT&T Bell Telephone Labs, then at Laval University from which he retired in January 2020. He has a keen interest in belief systems underlying major decisions made by political leaders and their social support groups.