I need first of all to explain how I have set out the evidence I have gathered [Order], and why. Next we’ll look at some debates over how evolution happens, or, according to some people doesn’t happen at all [The Prosecution]. I’ll then introduce myself to you and examine how we come to know what we think we know.
Our individual conception of the universe evolves through the input of conceptions we are exposed to as we grow up. New ideas always trickle gradually to various groups of individuals though. In the early 1600s Galileo completely upset our collective conception. He proved the earth moves around the sun. But a survey in France nearly four hundred years later showed that one third of the people there still believed the sun moves around the earth (Gohau 1991). Presumably some still believed the earth is flat.
In spite of the huge advances in the explanation of human origin made over the last 150 years a huge number of different theories still circulate about how we humans have arrived on earth. Most of these theories involve distorting, or selectively ignoring (perhaps unconsciously), relevant evidence. Many fossils have been discovered and forensic science has helped immensely in examining and interpreting all this evidence. A great deal of work has also been done on the ways genes work and how they, technology, culture and languages move, and change, through time and space. But in many parts of the world there has recently been an increase in religious extremism and growing unwillingness to accept the idea that we humans are basically a kind of ape.
Perhaps the one idea we can assume is true is that debate always improves our own ideas. The process produces a sort of hybrid vigour. Any opposition also clarifies our own ideas and theories. It focuses our point of view. To provide a framework for my explanation of the evidence I have decided to present this story as an argument against the evolution-deniers among us. I will use the idea that a defendant, Human Evolution, is on trial. Of course this trial is really about much more than just that. For example, cultural beliefs have always been used to justify both economic exploitation and the acts of terrorism committed in response. The trial is really about the attitude we have to our surroundings and the way we treat our planet and its inhabitants.
As we wind our way through the evidence I will imagine you, the reader, to be a member of the jury. But at various times you will probably consider yourself to be either a member of the defence or part of the prosecution. The defence case will explain exactly how, in the right circumstances, collections of genes and even individual genes spread through populations or into new regions. One of my friends has called this the wave theory of genetic, cultural and technological evolution. The jury will see that this theory totally explains our evolution from the apes until today. In fact it explains the evolution of all species at all times. Along with many other things. Even our collective and individual ideas and beliefs evolve in much the same way. I’ll begin the defence case once I’ve completed this introductory chapter. Much later, when I have explained exactly how the wave theory works, it will be sensible for us to follow our more recent history from this perspective.
The members of the prosecution are those in society who, for various reasons, claim the main outline of our evolution is not proven beyond reasonable doubt. At this point I would point out to the jury that members of the prosecution cannot actually offer any evidence, apart from ancient beliefs, to support a detailed, and certainly not a unified, alternative explanation for how, when, where and why we arrived on earth. Luckily we have a right as citizens in a democracy to question everybody’s motives. Although not all members of the prosecution belong to powerful or influential elements in society many of them do. Perhaps economics comes into it. Perhaps they hope their God is going to come back soon and, like their parents used to do, clean up any mess they make.
Order
Unfortunately I haven’t always found it possible to present all the evidence that supports a particular conclusion in its logical place. For example evidence that explains the human migration “North to Alaska” and then into the Americas also supports many conclusions I offer long before we reach that point. However for various reasons it is most convenient to present the particular evidence towards the end of my story. I’m sure the jury will still follow the various threads and not find this to be a problem though.
I admit that some items of the evidence may be subject to several interpretations. But surely the jury will be aware of the fact that it is usually possible to prove anything by selectively ignoring some, or even a great deal, of relevant evidence. Politicians and other powerful and influential people use the technique expertly. It’s usually successful. We cannot all know all the evidence. Although I realise many members of the jury will already know a great deal of the information presented, I’m sure you will all enjoy having it gathered together in one place and at your fingertips. Others of you will know less about the subject and I hope you find it as fascinating as we members of the defence do. Besides there is a difference between blindly accepting that we evolved from apes, and having the knowledge of how it happened. And it helps us understand events today.
The evidence I invite the jury to consider will concern the past. You might be tempted to say our ancient past is not important. But I would like to point out that our conception of the past and our beliefs about it influence our actions in the present. And of course these actions, in turn, will influence our future. I would suggest, though, in order to understand the past, let alone the future, we need first to understand the present.
In Part I - “Beginning” I will therefore first of all examine what we know about you, the individual person, and I explain how genes work. I then expand the view to include your progressively more distant relations, neighbours and friends. Even to the distribution of different human types around the earth today (“The Human Star” [A Map]). Although the defendant is Human Evolution along the way I will call on evidence from other creatures, and even from plants, to explain various aspects.
In Part II - “Migration” I use this evidence from the present to move slowly back into the past. New Zealand is one of the most recently settled regions on earth. To explain how the wave theory of evolution works I therefore use what we understand of the evolution and eventual mixing of the two main groups of people, Pakeha and Polynesian, in my home country.
In Part III - “Knowledge” I widen the perspective through both time and space. I show that these processes at work in New Zealand also explain all the fossil and genetic evidence for the evolution of all the various kinds of animals, birds and plants, along with the patterns of their distribution around the earth.
In Part IV - “Wandering” and Part V - “Conquest” it’s time to turn around, and start at the beginning. The jury will then be able to follow, examine and understand the meandering strands of our species’ evolution since our separation from the other apes, “The First Point” [Origin].
This will leave us with the problem of where to finish.
It will be least complicated to finish when we arrive at history. By definition history was not possible until people were able to record their version of events by writing them down (“Mythconceptions” [Oral History]). Writing seems to have begun near the eastern end of the Mediterranean Sea (“The Last Point” [The Eastern End]). Probably for that reason many political, philosophical and religious ideas through much of the world have their origin in the interaction of culture in and around that region. History begins there. In Part V the wave theory will help the defence explain the origin and perspective of these histories. For example the jury will see that the Old Testament of the Bible records such events as the Hyksos migration from Egypt and the migration of the Sea People. And many islands in the Mediterranean were, like the Pacific Islands, among the last places humans occupied. For these reasons the defence will call the Mediterranean Islands “The Last Point”.
The jury will also find that the history of the Mediterranean’s occupation will actually bring us around in a big circle. I’m confident that by the time you have completed that circle you will accept the defence’s interpretation of the evidence. No doubt various members of the prosecution will still disagree with many of these interpretations, but I’m afraid they’ll have to tell you themselves which ones they individually disagree with.
You will be able to see the layout in more detail, and go directly to most sections, from: 'Contents - Finding Your Way Around'
Because it has been so important in human history the defence will examine the evolution of culture at times. And technology. The distribution of various technologies and cultures reveals a great deal about human migration, expansion and evolution. This evidence will help the defence explain the wave theory. Of course the jury will realise it’s possible for a single person to spread culture, especially technology or an idea, and a genetic mutation must first arise in a single individual. But technology and many aspects of culture have always travelled faster and usually further than genes.
Although technology is really a part of culture the defence case will look at technology separately. Technology usually leaves evidence in the archaeological record whereas most other elements of culture don’t show up so well. It is also almost certain that in the very early stages of our existence technology was actually transmitted without language. Chimpanzees use basic tools for example.
The defence defines culture as being the things we have to learn that make us part of our social group. In their natural state most animals have to learn survival techniques off their older relations and in many ways this can be thought of as being culture. The study of wild chimpanzee and gorilla societies is especially interesting for this aspect of our evolution (see for example Fossey 1983, and Goodall 1990). But within the concept of culture the defence includes here only those things we learn through language: knowledge, beliefs, music, art, games, rituals, traditions, ideas, etc. (and obviously the language we speak is part of our culture). In fact the jury will see that this whole case is the result of a cultural exchange of knowledge accumulated by a huge number of humans ranging from friends and neighbours to people I have never met, including many who died long before I was born. You can probably already accept that culture evolves. In fact the defence will argue that technology and culture even obey much the same biological rules that species do. No doubt a general acceptance of the wave theory of genetic, cultural and technological evolution would ultimately lead to a change in culture.
The Prosecution
The prosecution are those of us who, perhaps to make money off others of us, maintain the defendant doesn’t exist. They constantly chant that there can be no absolute proof of Human Evolution. Of course it is very seldom evidence provides “absolute proof” of anything. It can only suggest probabilities. The defence would remind the jury that there is actually a totally overwhelming lack of proof for any theories the prosecution offers for our arrival on earth. The prosecution’s proof of their own beliefs simply involves pointing at particular ancient books. The only evidence they offer is to point at the current gaps in our knowledge. The defence suggests that the prosecution’s case relies totally on the theory of negativity: life couldn’t have evolved because it wouldn’t display the complexity it does if it hadn’t been created. Follow that?
The defence asks the jury not to be distracted into considering any other cases evolution-deniers have brought. These include “The Origin of Life” and “The Origin of the Universe”. We’ll look briefly at them in “Time” but these cases are best heard separately. And we should stick with what we can easily prove beyond reasonable doubt, Human Evolution from apes until today.
Besides, even many supporters of the modern idea of Intelligent Design, for example, would not dispute either the pattern or the time frame for Human Evolution suggested by the evidence the defence will present. They simply believe their God has had a purpose in guiding this evolution, from ape right up until today, especially during the historical events covered in “The Last Point”. A supporter of Intelligent Design (Wells 2000) concedes: “Obviously, the human species has a history. Many fossils have been found that appear to be genuine, and many of them have some features that are ape-like and some that are human-like”. The defence will offer these fossils as evidence later during the trial.
Of course even a very casual look at the evidence shows us at least some evolution has occurred, even if only a little bit. If we accept for now the widespread belief that humans descend from just one couple the only possible explanation for the variation we see in humans today is some form of evolution. A closer look at the evidence shows us that different species can actually be classified into groups that seem to be related. Members of the prosecution often explain this by claiming that various “kinds” were created, which they admit then evolved into these groups of species. But they are extraordinarily secretive as to exactly what kinds were created, and when.
The Defence
Not surprisingly the prosecution prefers drawing attention to disagreements among the defence rather than pointing at their own much more extreme differences. Members of the defence all agree that humans have a close genetic relationship with the apes of Africa: the chimpanzee and gorilla, and all three have evolved from a common ancestor. Several interpretations are possible for the evidence surrounding this common ancestor, though, and we’ll return to this when we reach “The First Point”. By then we’ll be able to use the wave theory of genetic, cultural and technological evolution to interpret the evidence.
The main disagreement within the defence concerns two conflicting theories concerning the pattern of our evolution.
We could call the first of these the “single origin” theory. This states modern humans evolved in Africa one or two hundred thousand years ago, moved out of that continent at some time and replaced all earlier human types. Genetic evidence showing all humans alive today share a male and a female ancestor supports the theory. There is also some fossil and other genetic evidence for the single origin theory. Supporters believe this is how evolution usually works; a small group expands and takes over. The theory has the advantage that it coincides, to some extent, with widely held cultural beliefs. It may even derive from them. In fact the two ancestors are often referred to as “Y-chromosome Adam” and “mtEve”.
The “spread origin” theory states humans have been what can be defined as a single species for much more than just the last 200,000 years. Our evolution has been by change and gene flow, the continuous separation and intermingling of human populations. The theory’s supporters suggest the evidence for mtEve represents something far more complicated than what has generally been promoted to the public. They believe that no species, including the human species, descends from a single individual, a single couple or even a single small group. But people always demand simple answers to complex questions.
Me
I must stress that this is my personal presentation. I’ll point out when it is specifically my interpretation but at other times I assure the jury that the interpretation offered is widely accepted by scientists such as anthropologists, zoologists, botanists, ecologists, geneticists, geologists, archaeologists, palaeontologists and linguists. Most of them would agree with most of my explanations but the jury will see that at times I offer an interpretation that scientists from one side or the other of any debate might not agree with.
People who specialise in the various sciences can perhaps become too involved in their own particular field to be able to look objectively at all the evidence. My training is in the more general field of agriculture. Agriculture requires knowledge of animal behaviour, practical animal and plant breeding and ecology, as well as an awareness of climate fluctuations, geology and an interest in nature generally. In fact farmers are trying to influence evolution every time they decide which animals to breed from and what weeds to destroy. They actually make better decisions if they are aware of this.
I have brothers who have been dairy farmers and because our parents were farmers I had the good fortune to be brought up on one. Farmers are all involved with the practical side of genetics. They usually notice that if they form a hybrid, or a cross between two different animal breeds, the individual or line of individuals they finish up with has a mix of characteristics from each original parent breed. In fact many characteristics are sort of halfway between the two. I’m confident that after examining all the evidence available you will accept that the evidence reveals at least some influence of the spread origin theory. The single origin theory requires selectively ignoring some of the evidence.
Modern developments in agriculture, especially in plant and animal breeding, provide us with a great deal of information about how this sort of evolution works. But people in the industry are often reluctant to use the information to support the defendant. It might involve them in controversy and perhaps alienate some of their clients. Many probably also lack time to find all the information.
I have been a musician for most of my life and through my interest in various types of world music, I have noticed that as the many tunes and musical styles move around the world they combine and alter, they change. In other words music evolves. Music is a part of our group’s culture and reinforces the sense of belonging to that culture. Historically the role of a musician in many societies has been to recite the genealogies, the history and the mythology of people in that society. Unfortunately I haven’t yet been able to put my story to music. However I do use several phrases many times and you may call these choruses if you wish. Of course you can choose for yourself the music you use as accompaniment while you study the evidence.
You
You will find that, like most things, the whole idea is stunningly simple to understand once you grasp it. Unfortunately, also like most things, it is difficult to explain simply otherwise it would be already totally accepted. This is not a straightforward story. Our family history is the result of diversification, amalgamation and interaction with other humans and other species (plants, diseases, animals etc.), and even changes in the earth itself. Because we can be sure the prosecution will very quickly pounce on the slightest gap in the evidence the jury will find this case at times becomes quite detailed and contains some technical terms. Fortunately it’s not necessary for you to remember the details in order to follow the story. You may even be able to follow it simply by looking at the maps, or by starting at “The Last Point”. Once you understand it you will be able to explain it to others.
The defence has tried to keep the number of “Witnesses Called” (in the form of references) to a manageable level. The reference given is the one members of the jury should easily find through a local library or on the Internet, but it is not necessarily the primary reference. If you are interested in following a particular subject up you should have no difficulty finding the primary references through the ones given.
The prosecution often claims there has been a huge conspiracy. They suggest that we, the defence, have somehow persuaded all these witnesses to make up evidence in support of the defendant. You will come to realise that the evidence many witnesses offer was not originally directly connected at all to the defendant. Most of the witnesses didn’t actually set out to provide evidence in support of the defendant in any way. In fact many may still not be aware of the significance of their evidence.
A quick word about dates. Most dates used in this case have “about” in front of them. Again the prosecution seems to have trouble with this. They expect the defence to be able to say that, for example, the Polynesians first arrived in Hawai‘i at 4.25 p.m. on the 23rd of August 432 AD. Surely “about 400 AD” is near enough. Modern dating methods such as carbon dating are always presented with a margin of error but this doesn’t mean they are therefore totally wrong and can be dismissed. Political polls also have a margin of error. It’s mainly the politicians who are shown to be losing who dismiss the polls’ general accuracy though. “About 30,000 years ago” is obviously much longer than “about 3000 years ago”. Interestingly you will find that members of the prosecution who criticise the lack of precise dates for the various stages of human development seldom provide any real evidence for accurate dates to support their own beliefs.
The Chinese Drover’s Very Clever Dog
There is one last point to make before we get this trial properly under way. We can quite easily come to the wrong conclusion; the conceptions we have accumulated encourage us to juggle the evidence to make it fit our beliefs. These beliefs are a product of how we are brought up. And we usually assume our own beliefs are superior to any others. They are the ones we know best.
We are all products of our cultural environment (Howe 2003). We are all completely unaware of what shared beliefs and personal biases we bring to our understanding of the world and how it works. Our conception of the universe is slowly built up through our lifetime, and the beliefs we form at each stage of our life as we grow up, especially those formed during early childhood, are very difficult for us to discard. In fact we can understand new information only by relating it to our pre-existing beliefs, or what the defence will later call our “Mythconceptions”. The defence suggests that widespread collective assumptions, preconceptions, and prejudices may have influenced generally accepted interpretations of the evidence concerning the defendant. Or even influenced the choice of what evidence has actually been either examined or ignored. Assumptions, preconceptions and prejudices certainly influence our individual conceptions.
My father grew up during the 1920s in the small country town of Eketahuna. There was a Chinese drover in the area. In those days (before stock trucks) people called drovers used dogs to move cattle from place to place. When my father was quite young he told my grandfather that the Chinese drover’s dog was very clever. When asked why he replied, “He understands Chinese”. Through his own assumptions, preconceptions and prejudices my father had presumed English would be a dog’s first language. It was obviously the normal language. All the people and dogs he’d had anything to do with understood it. And none of the other dogs he’d ever seen understood Chinese. The Chinese drover’s dog may well have been very clever but the fact it understood Chinese is not relevant evidence. This is an example of how what we already accept as being true prevents us from looking at the evidence objectively, or even at all of it. This affects our conclusions.
The problem is by no means confined just to children. In fact the defence will use the expression “Chinese drover’s clever dog syndrome” as one of the choruses as the trial proceeds.
No doubt many members of the prosecution will question the defence’s comparing humans with birds, animals and plants. But surely it is the prosecution who must first provide evidence to prove to the jury exactly how, why, and in what specific ways, humans differ. The defence suggests that the idea there are two sets of biological rules, one for humans and one for the rest of nature, may be our first example of Chinese drover’s clever dog syndrome, juggling the evidence to make it fit pre-existing assumptions, preconceptions and prejudices.
See next :: Human Evolution On Trial - 'Chromosomes and DNA'
Witnesses Called
Fossey, Dian (1983) Gorillas in the Mist. Penguin, England.
Gohau, Gabriel (1991) A History of Geology. Rutgers University Press, New Brunswick, USA.
Goodall, Jane (1990) Through a Window. Houghton Mifflin Company, Boston.
Gore, Rick (2002) New Find. National Geographic, Vol. 202, No. 2, August.
Howe, K. R. (2003) The Quest for Origins. Penguin, New Zealand
Wells, Jonathan (2000) Icons of Evolution. Regnery Publishing, USA.
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