The tenth anniversary of the human genome has been marked by some striking new genetic insights into human evolution and diversity. Do these new discoveries have any significance for the dialogue between science and religion in general, or for our sense of human uniqueness in particular?
The publication of the Neanderthal genome sequence in May 2010 set the pace. Not surprisingly—given that our last common ancestor with the chimpanzee was around 5 to 6 million years ago, compared to a mere half a million years for our last common ancestor with the Neanderthal—it turns out that we are genetically far closer to the Neanderthals than to the apes. In all, only seventy-eight changes in the genetic letters (‘nucleotides’) that would change the amino acid sequence of particular proteins were found in the Neanderthal DNA that were the same as the chimpanzee sequence but different in the human. Amongst other differences, 111 duplications of small DNA segments were found in the Neanderthal but not human sequence. Genetically we are closely related twigs on the great evolutionary bush of life.
But we knew that already. More surprising for many was the provocative finding that non-African humans are genetically closer to Neanderthals than African humans. In fact, the European and Asian genomes that were sequenced appear to contain one to four percent DNA of Neanderthal origin, and the gene flow that occurred appears to have been almost entirely from Neanderthal to human, rather than vice versa. How come? The most likely scenario is that there were a few instances of sexual reproduction between Neanderthals and human individuals belonging to the population that is thought to have emigrated out of Africa to populate the world sometime after seventy thousand years ago, explaining why the Neanderthal DNA sequences are not found in African genomes. The contribution of the Neanderthal genome has remained in European and Asian populations ever since.
To put this in perspective, most of our genes are very similar anyway to those found in Neanderthals and chimpanzees, and to other mammals like mice. We all share a “how-to-build-a-mammal” instruction manual, and the relatively minor genetic differences between us (minor relative to those we share in common) are the icing on the cake, as it were, that make us a human rather than a mouse, a chimp or a Neanderthal.
The year 2010 saw yet another twig appear on the hominin branch of the evolutionary bush, this time one even closer to the Neanderthals than our own. This story begins with the discovery by a Russian team of a sliver of finger bone from a remote Siberian cave in the Altai Mountains, known as the Denisova Cave. The team stored it away, thinking it was from one of the Neanderthals that frequented the cave between thirty thousand and forty-eight thousand years ago. But when DNA extracted from the bone was eventually sequenced, the results—published just before Christmas—revealed a population distinct from both humans and Neanderthals.
The finger appears to belong to a novel hominin population that shared a last common ancestor with Neanderthals more recently than humans, and overall is genetically closer to Neanderthals than to humans. It is too early to say whether the so-called ‘Denisovans’ represent a separate species and fossil data will be required to clarify that question. But what the results do suggest is that Melanesians—the inhabitants of Papua New Guinea and islands northeast of Australia — have inherited as much as one-twentieth of their DNA from the ‘Denisovans’, indicating that some limited inter-breeding took place between these ancient populations. Most fascinating of all is the idea that multiple hominin lineages were coexisting in Europe and Asia, along with modern humans, as recently as twenty-thousand to forty-thousand years ago.
Do these findings have any particular theological significance? It is difficult to know why this should be the case. In the Judeo-Christian tradition humankind uniquely is made “in the image of God”. The suite of capabilities that emerged during human evolution is necessary but not sufficient to do justice to this much discussed theological insight. Our particular genetic instruction manual generates large frontal lobes, advanced cognitive abilities, rationality, language, consciousness and the ability to choose between right and wrong. It is this suite that gives us the ability to pray, worship and engage in communal religious practices.
But the idea of being made “in the image of God” is not encompassed simply within a static list of such human qualities. Theologians have drawn attention to the dynamic, relational aspects of the concept. It is humanity-in-relation-to-God, together with God-given responsibilities to humans in relationship with each other, that are thought to be more central to the idea. When did such spiritual capabilities and responsibilities first come into being? It is really difficult to know, but the answer certainly seems more rooted in God’s intentions and purposes for humankind than in genetic change per se. Students can spend a long time being trained in the finer points of drama, but the play only gets off the ground when the actors are finally given their lines.
It seems quite likely that more twigs will continue to appear on the hominin branch of the bush of life as genomics continues to extend its reach. Such discoveries as such do not appear to raise any new theological questions. But other 2010 discoveries did highlight two genomic insights that do have relevance for religious views of human identity. The first insight comes from further Genome Wide Association studies that continue to subvert any lingering commitments to genetic determinism, for example the idea that there are genes “for” a particular human trait. The second insight comes from the finding that we are all more genetically different from each other than we realized even a few years ago. Genetics is underlining the uniqueness of each human individual. By the end of 2011 it is estimated that more than 30,000 human genomes will have been sequenced. Watch this space.
Theologians have spent many centuries mining the rich vein of the ‘image of God’ metaphor. Central to the idea is humanity with spiritual capabilities and responsibilities, equipped for moral decision-making and a relationally rich life in community. Historically, the idea has contributed to the conviction that each human individual has an absolute value, independent of their ethnicity, educational level, health status or income.
Do recent advances in genomics threaten or support such a view of humankind, or are they just neutral? Irrespective of one’s belief in God, or not, this is of more than passing interest. Imagine the poor person wrestling for years with the great questions of life and finally deciding to become an atheist, only to then be informed that a cognitive bias derived from his particular set of genetic variants made that decision pretty much inevitable anyway. Such news might be equally unsettling for the person who had just struggled to faith following years of agnosticism. Our deepest human feelings are closely connected with the idea that we choose our own path through life.
The flourishing of genomics in the early part of the 21st century has certainly conveyed the message to many that one’s destiny is written into one’s genome. Whereas scientists are generally scrupulously careful not to give the impression that there is any such entity as a “gene for” some human trait, by the time the latest discovery appears in the media, such caution is often thrown to the winds. The past year has seen the trumpeting of a “gene for happiness,” a “kindness gene” and a “believer gene.” It is not even a question of education, but “genes are to decide” if you are a “caring person.” Genetic testing websites assure us that “your genes are a road-map to better health,” and we all know that road-maps are fixed. Small wonder that there is a creeping genetic fatalism around that subverts the idea of personal responsibility.
Fatalism in itself impacts on human behavior. Studies have shown that subjects exposed to the writings of authority figures doubting free-will are then more likely to cheat. Conversely, workers convinced of the reality of free-will are rated higher in the work-place than those whose beliefs tend more towards determinism.
The reality is that recent genetics research has continued to move steadily away from any notion of genetic fatalism, highlighting the sheer complexity of the genome, and providing some fascinating examples of the ways in which our choices impact upon our own genomes. There is no gene “for” any complex human trait because in fact genes encode proteins or other types of information-containing molecules, and thousands of genes collaborate together during human development in interaction with the environment to generate the unique human individual that each person represents. Those requiring an introduction for the non-specialist are referred to “The Language of Genetics.”
Epigenetics adds further layers of variation and complexity. This refers to the chemical modifications of the DNA that cause genes to be switched on or off. It is such epigenetic modifications that generate the 220 specialized tissues of our bodies. Such acquired changes can even be inherited across several generations, certainly in plants and animals, and maybe in humans as well. In choosing to smoke, drink in excess, or take drugs, we also choose to modify our genomes.
So it turns out that even identical twins are not really genetically identical, developing different profiles of epigenetic modification as they go through life. This no doubt contributes to the otherwise surprising result that the age of death of identical twins, who share identical genomes, is comparable with that observed in non-identical twins, whose genomes are as different from each other as any two sibs. In one study of 184 pairs of twins in Spain, the difference in the age of death between the identical twin pairs was seven years on average, but such averages hide the fact that the age differences ranged from a couple of weeks to eighteen years. In the case of the non-identical twins, the difference in age at time of death was nine years, and the range was three to nineteen years. So there was really not that much in it.
What would happen if there was a genetic marker that identified nearly everyone in prison, marking them out as genetically distinct from half the world’s population? What would that do to our ideas about genetic fatalism and convictions about moral responsibility? As it happens that marker already exists. Out of 131 countries worldwide, an average of 96 percent of the prisoners are male and, in this case, no complicated genetic studies are needed to know that the genetic marker that identifies this population is the Y chromosome. So universal is the correlation between the Y chromosome and criminality that we can safely say that no other genetic correlation will ever be found between a variant genome and criminality that surpasses this one. And yet we still hold nearly all males responsible for their criminal actions and put them in jail as soon as they’re convicted. Furthermore, we note that most people who possess a Y chromosome go through life without committing a crime. So having a Y chromosome, with its unique set of genes, does not “determine” human criminality, although clearly we cannot go to the opposite extreme and say that it is completely irrelevant for patterns of human behavior.
The point in citing such examples is not to suggest that our genomes have nothing to do with our lives. They certainly do, not least in their significant contributions to our personality differences. The point rather is that the latest results in genetics provide no grounds for fatalism, instead highlighting the richness and diversity of the human population, and our own moral responsibilities, including the challenge to be good stewards of our genomes.
An argument for the existence of God this is not. But for those of us whose world-view is shaped by the conviction that we humanity are made in God’s image, it is good to know that the latest genetics is consistent with such a perspective.
During the past year, the first results were published from the “Encyclopedia of DNA elements” project (‘ENCODE’), revealing that at least 20 percent of the genome, perhaps more, is involved in regulating the expression of its 21,000 protein-encoding genes. The “selfish gene” had its day in the sun, but has now been replaced by the image of a finely tuned genomic system in which each type of gene product cooperates via an intricate networking complex to generate the music of life. The vast array of epigenetic signals whereby genes are switched on or off ensures a steady flow of two-way communication between the genome and its wider environments.
The human as a complex, interactive and highly integrated system might not on the face of it seem a fruitful hunting ground for those who see the genes as pulling the strings of life. Nevertheless, the past year has continued to see a growing love affair between the social sciences and genomics. This is well illustrated by a recent article in Nature entitled: “The anatomy of politics—from genes to hormone levels, biology may help to shape political behavior.” The author writes that “An increasing number of studies suggest that biology can exert a significant influence on political beliefs and behaviors,” reporting that “genes could exert a pull on attitudes concerning topics such as abortion, immigration, the death penalty and pacifism.” The political scientist John Hibbing is quoted as saying that “…it is difficult to change someone’s mind about political issues because their reactions are rooted in their physiology.”
Geneticists have highlighted the suspect nature of such claims from a purely scientific perspective. But in our present context it is the way that the genetic results are reported that is most striking. Note the dualist language involved and its assumption of genetic determinism. Genes and physiology are seen as something different from “us” and “our mind,” and they seem to be controlling us, so we can’t even change our mind. Humans are presented as pawns of their biology, puppets dancing to the tune of their genetic masters.
What has all this to do with the “big idea” concerning human identity that the Imago Dei provides? More, it turns out, than initially meets the eye. The clash of ideas here between theology and science comes not at the level of the science itself, which, in this case, remains ambiguous and disputed, but at the level of the ideological packaging of scientific ideas. To see where the clash comes from, we first need to understand the revolutionary nature of the Imago Dei idea in its original context in the texts of Genesis.
For millennia it was uniquely the pharaoh or the king who was seen as being in the “image of a god” in the polytheistic political systems of ancient Egypt and Mesopotamia. Adad-shum-ussur, a court astrologer and cultic official in the seventh century B.C. royal court of Nineveh, made clear that the Assyrian king Esarhaddon is the very image of Bel (Marduk), the top god of that era:
A (free) man is as the shadow of god, the slave is as the shadow of a (free) man; but the king, he is like unto the (very) image of god.
Richard Middleton provides further examples in his book, The Liberating Image, which describes how the stratified urban society of great cities such as Babylon was structured politically, socially and economically round the king’s court and the cultic practices of temple worship of the various polytheistic deities of the city. Social destinies were unchanging because they were rooted in powerful creation myths. Power was in the hands of the privileged few and true freedom belonged only to the king, for only he was in the image of a powerful god.
Would Hebrew thinkers and writers have been familiar with this idea? Almost certainly, yes, since Israel had significant cultural and economic contact with both Egypt and Mesopotamia over prolonged periods, not least during their periods of exile. So how would the original readers of that wonderful theological essay, Genesis chapter 1, have understood these words?:
Then God said, “Let us make adam [humankind] in our image, in our likeness, and let them rule over the fish of the sea and the birds of the air, over the livestock, over all the earth, and over all the creatures that move along the ground.” So God created adam in his own image, in the image of God he created him; male and female he created them. [Genesis 1:26-27].
In its historical context, the implications were revolutionary: the kingly and priestly male roles previously allocated to the privileged few by a pantheon of gods were now being delegated instead by the one creator God to the whole of humanity, male and female. In a stroke the entire ruling and priestly structure of Mesopotamian society was delegitimized. The Imago Dei was being democratized and it was now humankind who were to be the significant players in the arena of earthly life, the mandate to rule underlying their new responsibilities. Above all, humanity was set free by the one true God to determine their own destiny, no longer under the yoke of all-powerful dictators, nor under the baleful astrological control of the moon and stars.
Yet, ever since, humans have become experts at re-enslaving themselves, refusing the responsibilities that come with free-choice and submitting instead to narratives of fate and destiny. It seems ironic that today it is not the creation myths of ancient Babylon but the ideological interpretations of biology that provide the narratives of fate, in which genes “pull” humans toward certain political views and people cannot change their minds because their convictions are “rooted in their physiology.”
“It’s in his or her DNA” is a new phrase becoming increasingly embedded in our language, referring to something that cannot apparently be changed. People have choices—they are the prisoners neither of their genetics, nor of their physiology, nor indeed of their environments. Human beings made in the image of God are free to chart their own destiny in a way that preserves human value and dignity. On that we can leave the last word to Abraham Lincoln: “…nothing stamped with the Divine image and likeness was sent into the world to be trodden on, and degraded, and imbruted by its fellows.”
Once we have a scientific hypothesis for how something exists, it is tempting to make the philosophical inference that this is also why it exists. Richard Dawkins (1976), as well as Michael Ruse and Edward O. Wilson (1993), do this in the evolution of human morality. Scientifically, they hypothesize that, once humans started living in large, complex social groups, individuals whose genes made them constantly selfish were punished by the group and therefore produced fewer offspring than individuals whose genes made them believe in an objective moral code. Moving into philosophy, Ruse and Wilson (1993) write,
Morality, or more strictly our belief in morality, is merely an adaptation put in place to further our reproductive end.
Important scientific theories invite philosophical and theological reflection. Dawkins, Ruse, and Wilson, have described their conclusions. But scientific theories are often compatible with multiple philosophical and religious interpretations. For example, Newton’s laws of motion and gravity allow several competing theistic and atheistic interpretations.
To avoid Ruse and Wilson’s philosophical conclusion, we need not dispute their scientific hypothesis about how morality evolved. We need only dispute their philosophical extrapolation as to why morality exists. Even if we restrict ourselves to an atheistic worldview, this extrapolation is questionable. Donald MacKay (1965) would call this an example of “the fallacy of nothing but-tery”. This is the assertion that a description of something at one level renders other levels of description meaningless. From our everyday experience, we know that a successful description on one level does not invalidate other levels of description. For example. one might assert that a Shakespeare sonnet is “nothing but” ink blots on a page (MacKay 1965). True, one way to describe a sonnet is to precisely specify the page coordinates of every ink blot. This description is valid and complete on its own level; however, one could also analyze the sonnet linguistically, emotionally, socially, historically, and on other levels. If one is programming an inkjet printer, the most important description is in terms of ink blot coordinates. For almost every other purpose in life, however, that is an unimportant level of description. In the same way, a complete evolutionary description of the existence of morality does not necessarily invalidate the truth, utility, or significance of other levels of description of morality.
If we do not restrict ourselves to atheism and instead allow for the existence of a creator, the extrapolation from how morality evolved to why morality exists fails further. Consider an analogy. Suppose an inventor builds a robot which could do a variety of useful things—mow the lawn, clean the house, grade homework, write book chapters, and so on. One thing this robot can do, given a complete set of spare parts, is build a replica of itself. Whenever the inventor needs another robot, she gives one robot a set of spare parts and has it build a replica of itself. Amongst all the software subroutines within this robot, there is a set of subroutines that govern the robot’s self-replication, including the replication of those self-replication subroutines. Would it be correct to say that the purpose of the robot’s existence is merely to reproduce those particular self-replication subroutines? Do all of the other software and hardware of the robot—which allow it to mow the lawn, and so on—merely further the reproductive ends of those self-replication subroutines? At one level, the robot’s hardware and software do serve to reproduce those self-replication software routines. At another level of analysis, however, those self-replication software routines serve the robot to produce more copies of itself. At still another level, those self-replication software routines serve the robot’s creator. The creator of the robot should get the last word as to which of those levels of description is most important.
In humans, does morality exist to further the reproduction of certain genes, or do those genes exist in order to allow for the production of new human beings who can behave morally? If human beings have a creator, the creator gets the final word on the question of purpose. The mechanism which the creator used to make those genes—whether de novo or via evolution—is secondary. The creator’s purpose in creating those genes decides the issue.
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