Doctrine of Man (Part 11)

In our lesson, we’ve been talking about the Doctrine of the Fall and we contrasted the traditional view of the Fall as a historical event involving Adam and Eve from a state of innocence into a state of corruption with all of the terrible results that that brought. We contrasted with that the modern view of the Fall which would interpret this story as purely mythological or symbolic; a story told in figurative language to describe the Fall that is universal among mankind. We all, in the course of our lives, fall into sin, and as a symbol of man’s fallenness and corruption before God.

Evaluation

Today we want to come to some evaluation of these competing views.

Now, on the one hand, Adam and Eve, as their very names indicate, do have a symbolic significance in the story. Adam just is the Hebrew word for “man.” So, in essence, Genesis 1 says that in the beginning God created man – Adam. This, I think, shows that he is a sort of general symbol of mankind. Similarly, Eve is referred to as “the mother of all living persons.” So, again, she has a kind of wider significance than just a historical person. Moreover, the narrative of the Fall is full of all sorts of symbolic or figurative elements like the tree of life, the tree of the knowledge of good and evil, the serpent in the garden who deceives the woman, and so forth.

Nevertheless, in spite of this obvious symbolic function of the narrative, it does seem to me that we also have good biblical grounds for thinking that Adam was an actual historical person. Let me mention four such factors.

1. There is no break in the narrative between Adam and indisputably historical figures. The story goes right on from Adam through Abraham and Moses and these are indisputably intended to be historical persons. There is no suggestion that the first part of the story is purely symbolic and then the later aspects are historical.

2. Adam is included in the genealogies that tell of the descent of historical persons. This is true both in the Old Testament and in the New Testament where the genealogy of Jesus is given in the Gospels. So Adam is included in the genealogies with the other historical figures just like a historical person.

3. Paul treats Adam as a historical figure in a number of places in the New Testament. For example, in his address on Mars Hill that is recorded in Acts 17:26 Paul says this, “. . . from one man he made every nation of men to inhabit the face of the whole earth, and he determined the exact times and places that they should live.” So here Paul, according to Luke’s account at least, says that all of the nations of men that inhabit the earth today are descended from one human ancestor – from one man. Paul refers to this man as Adam in various places in his epistles. For example, 1 Corinthians 15:45, “Thus it is written, ‘The first man Adam became a living being’; the last Adam became a life-giving spirit.” So here Paul refers to Adam as the first man and contrasts him with Christ who is the second Adam.[1] Also in 1 Timothy 2:13, Paul says, “For Adam was formed first, then Eve;” and then he says “Adam was not deceived, but the woman was deceived and became a transgressor,” referring to the Fall of man. So here again Paul refers to Adam as the first man who then fell into sin. Paul consistently treats Adam as a historical individual; someone who really lived, not simply as a symbolic figure.

4. As we’ve seen, Paul draws parallels between Adam and Jesus as historical individuals. Paul certainly believed that Jesus of Nazareth was a historical person. He parallels Christ with Adam as the second Adam. Remember we read last week that as through Adam – the first man – sin came into the world and spread to all men so through Christ life and forgiveness and redemption are made available to all men.[2] So there is a parallel drawn between Adam and Jesus as historical persons.

So it seems to me that, despite their symbolic function in the narrative, Adam and Eve are regarded by the biblical writers as genuine historical persons.

I think what we can say is that the Fall of man is a historical event that actually happened though it is told in a dramatic literary form involving figurative speech. The story of the Fall has been called, rightly I think, a historical drama. It is a dramatized, or figurative, story telling of an actual historical event, namely the fall of the parents of the human race into sin and separation from God.

Affirming the historicity of the Fall as I’ve done implies that the human race is descended from a single ancestral couple. It commits us to the monogenesis of the human race. Not merely that the human race originated in one place as opposed to multiple places around the globe, but monogenesis in a very peculiar sense, namely that there was an original ancestral human pair from which all of humanity is descended.

This traditional view of Adam and Eve has been vigorously challenged in recent years on the basis of the science of population genetics. Let me be the very first to say that this is a field about which I know little. Like most of you I am simply an interested student in these matters. But I want to lay out in a simple way something of the current controversy that arises from population genetics for the historicity of Adam and Eve. If you are like me you will be interested in reading more about this and trying to follow something of the debate.

In order to understand this controversy, it is important to understand that, according to the theory of evolution and contrary to popular impression perhaps, evolution does not proceed along an isolated individual line. It is not as though some sequence of individual reptiles evolved, for example, into the first bird. Rather, the idea is that whole populations evolve over time. So the ongoing front of evolution is not like a pointed spear, it is rather a broad front as a whole population of organisms evolves together over time. In this case, a whole population of reptiles would be evolving bird like characteristics. Similarly, in the case of human evolution, there is a whole population of hominids – man-like primates – which is gradually evolving characteristics of modern human beings. So, there weren’t originally two human persons – a couple – that were the ancestors of everybody else.[3] Rather, modern human beings evolved through a whole population of these hominids moving gradually toward more recognizable modern human forms.

Recent genetic studies have tried to determine the minimum size that that population of ancestral human beings could have had. How few of these ancestral human beings could there have been? One way to estimate the size of the ancestral population of humanity is by comparing the portion of the human genome, which is more similar to gorilla DNA (which we will symbolize here as G) than to chimpanzee DNA (that will be C). H then will be Homo sapiens – or human. [see Figure 1] According to the current evolutionary theory, human beings are more recently separated from a common ancestor to chimps and human beings than did this ancestor of chimps and humans from gorillas. The separation over time as you go vertically up the chart is that gorillas first separated off and then some time later chimps and humans separated off of the common ancestor from the common ancestor to gorillas and chimps and humans.

The interesting thing is that a portion of the human genome, or genetic structure, is perhaps, contrary to expectation, actually more similar to gorilla DNA than it is to chimp DNA even though humans and chimps are more recently separated and so you would expect them to be much more similar. In fact, I am told about 15% of the human genome actually resembles gorilla DNA more than it resembles chimp DNA. The idea of population studies is to explain how this could have happened. How is it that human DNA could be more similar in some respects to gorilla DNA than to chimpanzee DNA even though chimpanzees and humans evolved from a more recent common ancestor?

The theory is that the ancestral population for gorillas, chimps, and humans must have been sufficiently large that it could carry a variety of genetic traits. We can represent this by the red line. The gorilla genome evolved from that common ancestor of all three of these groups. Another genetic line evolving off of that common ancestor then went into chimpanzees. Still yet another line of DNA went into human beings. As a result of this, human DNA structure shares some of the characteristics that went into the gorilla genome but did not go into the chimp genome. This requires a large enough population of this ancestral group in order for different genetic structures to go off on these different branches. So as a result human beings resemble in their genetic structures gorillas more than they resemble chimps. In order to carry this diversity of this genetic material that population has to be at least several thousand individuals, it is estimated. So on that basis, the claim is that you never get down to just two individuals. There has to be a fairly large population of at least several thousand individuals in order to be carrying this sort of genetic diversity.

Notice that this presupposes the doctrine of common ancestry that we talked about earlier. It presupposes, or assumes, that humans, chimps, and gorillas are all evolved from some common ancestor.[4] Someone who denies that humans and chimps evolved from a common ancestor actually might take the greater similarity of humans to gorillas than to chimps in some respects to be evidence that they did not evolve from a common ancestor. Rather, they are simply built on similar design plans and that the human design plan selectively reproduces parts of the chimp genome and parts of the gorilla genome and that is why they are alike in some respects even though on the theory chimps and humans are supposed to be more recently evolved from each other. So the special creationist, I think, would take this same evidence not to be evidence of a large ancestral population but rather evidence against common ancestry and say that what we have here are common design plans that incorporate elements of each other but don’t necessarily show ancestry.

Moreover, even given the assumption of the doctrine of common ancestry, what this data enables us to estimate, it seems to me, is the population of the organisms that were ancestral to chimps and humans. What it tells us is that this population of non-human, non-chimp ancestors (whatever it was) had to be sufficiently large to carry the genetic diversity to explain how we have chimps and humans today that differ from each other with regard to this gorilla DNA. But even if that population were fairly large, who is to say that the genetic line that goes to human beings wasn’t carried forward by just two individuals. I don’t see anything in this data that would say even though this population had to have several thousand persons in it that the population that carried forward this red line could not have been just two individuals – two persons. So it doesn’t seem to me that this data is compelling for showing that the human ancestral population, as opposed to the pre-human ancestral population, had to be more than two persons.

More important direct evidence for the size of the ancestral human population comes from the genetic diversity of human beings today. Researchers have been able to sample the genetic diversity of present day human beings around the world and have been able to show that it exhibits a considerable degree of genetic diversity. The claim is that the evolution of this much genetic diversity among human beings today requires a minimal initial population of at least a couple thousand individuals and it could not have arisen from two people alone. If you originally just had two people evolving over time to the present day, you would not get the diversity in the human genome that we see in the present. Therefore, even if Adam and Eve were special creations of God – even if you deny common ancestry – still, from two persons you would not be able to generate the amount of observed genetic diversity today. This argument seems to me much more compelling. It doesn’t assume common ancestry. Even if Adam and Eve were special creations you still have the same problem. It doesn’t talk about the pre-human population. It is talking about the initial human population. How do you generate this much genetic diversity among living human beings from a single pair? It seems that you have to get down to no less than a couple thousand human persons.

What might one say in response to that? Notice that the argument assumes that the mutation rates among human beings were constant over time. In order to calculate whether this amount of genetic diversity could arise from an initial human pair, you have to assume a certain mutation rate that is constant over time. One might deny this conclusion by postulating accelerated rates of mutation in the early human population. One could see this as a result of divine intervention – that God accelerated the evolution of early humans so as to produce greater genetic diversity.[5] I don’t think that this would need to be an ad hoc or contrived move on the part of the defender of the historical Adam just to save the appearances. Rather, you will remember when we talked about the mechanisms that are behind the neo-Darwinian theory of evolution, namely random mutation and natural selection, we saw that those mechanisms operate far too slowly to plausibly explain the amount of biological complexity and diversity in the world today. Therefore, these mechanisms don’t seem to be adequate in and of themselves at the rate at which they operate to explain the observed biological complexity today. So the progressive creationist will postulate acts of divine intervention, either to cause mutation rates to accelerate that will drive evolution forward, or perhaps even acts of special creation in order to bring about the biological complexity that we see today to create new life forms. If you already believe that God is involved in producing accelerated rates of mutation in order to drive evolution forward then this really isn’t surprising if, in the case of human beings, he would have produced accelerated rates of mutation that would bring about the development of modern human beings. So I don’t think that this needs to be seen or criticized as a sort of ad hoc or contrived move. Rather, it fits in with what the progressive creationist would expect.

In any case, appeal to divine intervention to produce accelerated mutation rates may not even be necessary. Defenders of the historical Adam today note that these population estimates that we’ve been talking about are based upon highly idealized mathematical models which may not provide realistic population estimates. Fuz Rana, who is a scientist that works with the organization Reasons to Believe, has pointed out studies involving sheep and horses in which the original population size was known and yet the genetic diversity exhibited by present day populations is much greater than what the mathematical models predicted. He explains one such case involving sheep. I will quote from him here.[6] He says,

So the genetic diversity was four times what the model had predicted.[7] He says,

So natural selection actually accelerates the rise of genetic diversity because it has survival value in the struggle for survival.

In other words, had they not known that there were originally only two sheep placed on that island, looking at the genetic diversity exhibited by the present sheep using the mathematical models they would have over estimated the minimal size that that population would have had at any time in the past because the models did not take account of the accelerated rates of genetic mutation that were driven by natural selection.

If it is the case that natural selection can drive the increase in genetic diversity then that calls into question the assumption that the mutation rates have been constant over time for humanity, and hence it calls into question the population estimates based on that assumption.