This is a slightly longer version of the text of a talk that I delivered to the Agnostics Group in Melbourne, Australia on 06 January 2019
Scientists generally accept that the different species of life on Earth arose through a long series of changes, as described by the theory of evolution.
Some people disagree. They believe that God designed and created each individual species of life on Earth. Such people are referred to as creationists. Many creationists believe that science supports their belief, and they produce plausible scientific arguments. But these arguments often rely on misunderstandings of specific parts of science.
With all kinds of dogma, including science and creationism, the believers are not unanimous on all of what they believe. So, while most creationists will disagree about what I have to say about their beliefs, others may agree with me on at least a few issues
Last year, a well-structed lecture was presented to the Agnostics Group in Melbourne by a creationist who set out a series of arguments that claimed to show how various aspects of science disproved the idea of the evolution of organic species. Several sites on the internet contain similar arguments. The presentation also claimed that people who accept evolution believe certain things that are contrary to observed fact.
I disagree with most of the arguments, and with creationism generally. But I am not implying that creationists are lacking in intelligence. Some prominent scientists have had misunderstandings about areas of science that were outside their own specialisations. Sometimes, something that seems obvious can turn out to be untrue, and something that seems unlikely can seem obvious after learning about it.
In discussing the arguments that were put forward last year, and other arguments from other creationists, I will describe the relevant aspects of science. These might sound complicated or daunting, but I will explain them in everyday language. They are:
The first law of thermodynamics;
The second law of thermodynamics;
Genetic mutations;
Archaeology and anthropology;
Some other biological issues, and
The assessment of probabilities
I will also discuss what was said about the evolutionists’ apparently mistaken thinking.
The first law of thermodynamics
The first law of thermodynamics says, among other things, that matter cannot be created or destroyed. This is referred to as to the conservation of matter. The creationist’s interpretation of this was that, since “matter is constant”, inanimate matter cannot become living matter.
Matter being conserved it is not the same as matter being constant. And there is more than one way in which matter is not constant.
Molecules of matter are continually being formed, and molecules continually decay.
Some chemical elements can exist in more than one form, and can be changed from one form to another. Carbon, for example, has nine different forms. Diamonds, charcoal, graphite, graphene, fullerenes (i.e., “buckyballs”), nanotubes and the other forms are all pure carbon. Each is different from the others in such ways as electrical and thermal conductivity, specific gravity, compressibility, tensile strength, flexibility, transparency and colour. Their differences are the consequences of their particular structures. one way.
Water, and other compounds, and some elements, have solid, liquid, or gas states, dependent on temperature and pressure.
Furthermore, Einstein’s theory of relativity showed, and subsequent observations confirmed, that matter can be converted into energy in accordance with the well-known equation
e = mc2. The first law of thermodynamics has now become the conservation of mass-energy.
Radioactive decay turns elements into smaller elements and in the process converts matter to radiation. The fusion of chemical elements, that is combining two atoms into one, can produce larger elements, again converting some matter into radiation. Examples are the production of various heavier elements by fusion in the explosions of large stars, and helium atoms being combined by fusing hydrogen atoms in the sun.
So matter, itself, is not constant.
A different kind of constancy was also claimed. It was said that “the Confirmed Data” show that there is a “life-matter gap” and “biochemicals are not formed naturally from nonlife”.
But plants and some animals take in inanimate carbon dioxide, calcium, nitrogen and other chemicals and convert them into parts of their bodies. Several kinds of chemicals that compose parts of living organisms are also present in huge amounts in and beyond the solar system.
A couple of examples are methane and carbon dioxide. Our bodies consist mainly of water, which is plentiful in our oceans and in other parts of the solar system.
So matter is not constant, and inanimate matter can become part of living matter, and vice versa.
The second law of thermodynamics
Some creationists say that the second law of thermodynamics disproves the concept of evolution. Other creationists say that the existence of living organisms disproves the second law of thermodynamics. Neither is true. I will explain why they think these things.
An example of the second law of thermodynamics is that if something hot, i.e., with a high temperature, is in close contact with something cooler, i.e., with a lower temperature, then heat will transfer automatically from the hot thing to the cooler thing, making them closer in temperature. Heat will not be transferred from a cooler thing to a hotter one unless some outside energy is provided to increase the difference in temperature.
Temperature may be thought of as the pressure of heat, or, in scientific terms, the heat potential.
Voltage is electrical potential. The force of gravity also has a potential. The word pressure is generally used to refer to pushing.
Another example of the second law is expressed in the saying “water finds its own level.” Water readily runs downhill, but does not freely run uphill.
Differences of in all kinds of potential, not only differences of temperature, are continually becoming smaller throughout the universe. So the universe is becoming more uniform. On human timescales, it still has a long way to go.
The second law of thermodynamics also implies that patterns and structures will not, of their own accord, become more complex or more structured. They will tend to become less complex, or more “disorderly”. Examples are materials breaking down or rotting, and radioactive decay.
Living organisms are much more complex in their structure than inanimate matter, so it is not hard to see how someone would draw the conclusion from the second law of thermodynamics that complex new life could not arise from less complex inanimate matter, or evolve into increasingly complex organisms. It would seem to go against the universal trend. And it is not hard to see how someone might think that the second law is disproved by the existence of life.
With any device or system that appears to defy the second law of thermodynamics, there is always some external energy source that causes the change in potential to apparently “go in the wrong direction”. In charging a battery or pumping water uphill, and in every other case, you have to put in electrical or thermal or some other kind of energy.
So the birth and growth of organisms, and the evolution of new species, all of which are examples of increasing complexity, require continual inputs of energy. Where does this energy come from?
Every process of reducing differences of potential produces energy. Just as lifting water requires the input of energy, water running down-hill produces energy. Hydroelectricity is a practical example. This is the other side of the second law of thermodynamics. There are many sources of energy that enable the development of life and many other things.
Most organisms on Earth get their energy intake, directly or indirectly, from sunlight and other radiation. Sunlight is produced by the fusion of hydrogen to create helium, a process in which matter is converted into energy. On Earth, sunlight causes or enables chemical reactions, which store energy. This enables new life to develop.
Many organisms obtain energy from the chemicals that are in the bodies of other organisms that they eat. Others obtain energy from differences in the temperatures in their close environment.
Being aware of the universal trend towards uniformity and towards the decrease of complexity, makes it easy to overlook, or be unaware of, the possibility of nature providing energy for organisms to grow and function and evolve. Some creationists might say that any external energy input was provided by God. It could be said that if God created nature, then God provided the processes for evolution that seem to defy the second law of thermodynamics. This might provide an explanation to satisfy creationists.
Genetic mutations
In living organisms, new cells are created in the processes of growth of the body and the replacement of old or damaged cells. There are often errors in the copying of the cess’ DNA. Most of the cells have processes for checking for such errors, and processes for repairs. But not every error gets repaired. Unrepaired errors constitute mutations to the DNA of the affected cells. If mutations occur in sperm or ova there is a chance that they will be reproduced in the next generation. It is these mutations that cause the difference between all individual organisms of every kind.
Some creationists say that mutations can never lead to any advantage, so evolution cannot occur. Most mutations have little or no effect. Some will cause problems ranging from very mild to fatal. A small few will give some advantage or some change that might produce some advantage after future mutations.
Such mutations, and their consequent unique physiologies, and unique sets of physical and mental capabilities, have enabled selective breeding of many species of domesticated animals and plants, giving them significant designed differences from their ancestors.
There is also a process called natural selection. It this process, some mutations give some individual members of a wild group a likelihood of being more prolific than other members of their group. That is, they provide more offspring surviving to adulthood. Being more prolific is the result of being better adapted to the particular environment. After several generations and further mutations there will be further adaptation of some members of the group. And the better adapted strains will predominate. This process is accelerated when environments change. Over time, continued chance mutations, and consequent adaptations to new and existing threats and opportunities, produce different species. This process is very much slower than planned selective breeding.
Creationists say, “natural selection [i.e., adaptation] is not evolution”. I would say it is evolution, but not necessarily the evolution of a new species. One swallow doesn’t make a summer.
It takes a lot of adaptations, and there must be significant changes, to produce a new species. But there is no clear-cut way of determining when a variety of a species becomes a new species. The common criterion for distinguishing between different species and different varieties is to take fertile typical members of a species and fertile members of the opposite sex from the questionable group. To be considered to be the same species, they must mate, and produce offspring that are able to produce offspring. Biologists think this test can give positive and negative false assessments.
There are species that have different variations in differing regional habitats. The ones at one extreme of difference are unable to breed with ones from the other extreme, but each can breed with varieties closer to themselves.
There are more than 30 different biological definitions of species.
Creationists disagree that there has been enough time. I will discuss this in more detail in a later section of this essay.
The significant causes of adaptation and speciation are continued varying of environment, having a lot of fecund adult offspring, and having enough time for evolution to occur. There has been enough time for Earth’s biota to do a lot of evolving.
An interesting argument relating to adaptation is the concept of “reversion to type”. Charles Darwin wrote ,“Our domestic varieties, when run wild, gradually but certainly revert in character to their aboriginal stocks”. This implies that nature goes in the opposite direction to evolution, and it looks like a strong argument. For Darwin it was puzzling. But he missed one important point.
If a group of mixed varieties of a domesticated species, for example, the different breeds of dogs, runs wild in a particular area for several generations, and its members freely mate or otherwise fertilise with each, there is likely to be a decrease in the physical differences between the members. They will slowly select naturally to something like some previous wild predecessor. But their new characteristics will depend on their adaptations to recent environmental conditions. They will retain traces of the differences of their ancestors’ selective breeding. This is not reversion to the original type and it does not disprove evolution.
If kept isolated for many generations, the group is likely to become significantly different from its ancestral form, and ultimately become a new species. There is evidence of this still happening in a very wide range of species of animals and plants, and in most species of bacteria.
All of this suggests that evolution is essentially a competitive process. But there many instances of cooperation between different biological kingdoms. This is most common in the form of symbiosis, where two species depend on each other. This occurs widely between plants, fungi and bacteria. Common examples are corals and lichens
All of this suggests that evolution is essentially a competitive process. But there many instances of cooperation between different biological kingdoms. This is most common in the form of symbiosis, where two species depend on each other. This occurs widely between plants, fungi and bacteria. Common examples are corals and lichens
Some creationists say that the organs of the bodies of humans and animals “came fully developed” and have “irreducible complexity”. This means the organs could not have performed their functions if their structures were less complex than they now are, and they did not gradually develop through a process of evolution. What does the evidence say?
The structures of biological organs are continually being investigated, categorised and recorded, and their operations are well understood. They generally, and specifically the ones referred to as being irreducibly complex, are found to have simpler counterparts in present or extinct species. And the very first ones? They appear to have come from simple changes that allowed the development of new types of capabilities, without necessarily providing any initial advantage.
The evolution of bodily organs can be illustrated using the development of the eye, a complex organ that creationists often quote, saying its evolution is an “impossibility”.
With the eye, a long series of tiny steps started with a mutation that produced a blob of tissue that happened to cause a reaction affecting the organism when light fell on it. Some simple organisms still have something like this. Successive mutations sometimes provided additional advantage, such as registering the direction of the light, improving focus, and distinguishing detail, colour and movement. This produced the many different types of eyes observed among a wide range of species. For each change to be viable, other parts of the organism had to be able, perhaps initially not very well, to take advantage of it. It is possible to see this progression in both the bodies of the relevant species and in their DNA. There have been several sequences that have independently led to the development of eyes.
Anthropology and archaeology
Anthropology is the history of human cultural activity. Archaeology is the branch of Anthropology that studies the history of human artefacts.
The lecture last year included a section that said that “archaeology and anthropology show civilisation started suddenly around 3000 BC”, along with art and language. It also said that there were gaps in the fossil record.
The idea of civilisation starting suddenly is a misrepresentation of the history of the many different human societies. The various groups of people around the world gradually increased in population and in the sophistication of their technologies, their art, and their explanations of the workings of the world. There were many setbacks and reversals in all these developments. There is no criterion that sharply distinguishes the beginning of a civilisation.
There is evidence of sophisticated human cooperation and aggression going a long way earlier than 3000 BCE. We have evidence of Australian Aborigines giving considered treatment to their dead tens of thousands of years ago. There are sophisticated 35 000-year-old paintings on the walls of limestone caves. There are remains of cities and large complex structures going back more than 8000 years.
But it is hard to see any relevance of the arrival of civilisation to the issue of the diversification of species.
There is an extensive amount of manufactured and fossil material that displays both the diversity and the sequences seen in archaeology and anthropology. There are gaps, but it is easy to “join the dots” and see the relationship within the sequences. Geological and genetic evidence identify the periods of time when the various species lived.
Creationists challenge the scientific dating of fossils, artefacts and geological events. They also challenge the ages of cosmological events and objects. They assert that the use of such things as red shift and radioactivity is unreliable. Some think the age of the earth and the universe is only a few thousand years. Cosmologists and geologists think in billions of years.
Scientific dating techniques depend on well-established procedures. The observational and theoretical findings are backed up by alternative independent physical processes. Extraneous conditions sometimes reduce their precision. Some techniques are reliable for a particular period in time, but there is enough overlap for assessments to be independently confirmed. The effects of such inaccuracies would need to be inordinately greater than they are to produce figures that would suit the creationist datings or challenge the theory of evolution.
Creationists quote dark matter and dark energy, which have yet to be identified or detected, as proofs of the unreliability of science as understood by scientists. There are lots of things that science has observed in the universe but not explained. New theories and discoveries solve some mysteries, introduce new mysteries, and often correct or enhance existing scientific theories. This expands the scope of science: It may change it but it does not invalidate it. Discovering the underlying nature of dark energy and dark matter, or solving other scientific mysteries, would not be likely to support the concept of the divine creation of species on Earth, or elsewhere.
Some creationists refer to the anthropic principle as a proof of divine creation of the universe, and extend that to proof of divine creation of individual species.
The anthropic principle has many versions, but as the name implies, it has something to do with humanity. From the creationist point of view, it argues that there must have been a creator to make the universe the way it is, and be suitable for humanity. The creator then designed and created the many species of organisms, a very large percentage of which are now extinct.
At the universal scale, the anthropic principle refers to the fundamental constants of physics, which relate to such things as the strength of the forces of gravity and electromagnetism etc., and of certain other measured aspects of the universe. Creationists note that scientists say that, if the values of these constants were different from what we have measured them to be, the universe could not support life, or even exist. The creationist interpretation is that this proves that the creator chose these fundamental values to make the universe the way it is.
From the scientific viewpoint the origin of the universe is just one of the scientific mysteries. What caused the big bang? If it was the divine creator, what caused the existence of the divine creator. At our present state of knowledge, the origin of the universe could equally be natural or supernatural.
But none of this disproves the theory of evolution.
Other biological issues
Creationists insist on the “uniqueness of humanity” as distinct from other organisms. The genetic evidence shows that modern humans have a range of ancestral lines, with different inclusions of Neanderthal and/or Denisovan and other earlier hominin DNA in their genomes. We come in a range of colours and shapes. While we are all individually unique, humans also have a lot in common with other animal species, both genetic and physical. Humans and chimpanzees have around 95% of their DNA in common, but the DNA of humans and other species is continually changing. All species are biologically connected in some way. All life on Earth depends on and is controlled by DNA and/or RNA.
Creationists insist on the “uniqueness of humanity” as distinct from other organisms. The genetic evidence shows that modern humans have a range of ancestral lines, with different inclusions of Neanderthal and/or Denisovan and other earlier hominin DNA in their genomes. We come in a range of colours and shapes. While we are all individually unique, humans also have a lot in common with other animal species, both genetic and physical. Humans and chimpanzees have around 95% of their DNA in common, but the DNA of humans and other species is continually changing. All species are biologically connected in some way. All life on Earth depends on and is controlled by DNA and/or RNA.
Creationists have pointed out that, for life to have emerged from inanimate matter, enzymes and other catalysts would have been necessary, along with particular kinds of stored information. Scientists accept that several very unlikely steps, including the production of enzymes, etc., would have been needed for life to have emerged on Earth. How this happened is still unexplained. But for evolution, all that is necessary is the ability to reproduce offspring that will also reproduce, and the continued occurrence of mutation.
Assessing probability
The most common claim against evolution concerns the complexity of life forms and processes. They are “too complex to happen by chance”. It is easy to understand why people think this, when considering such things as the fine balances between the body processes that are necessary for the functioning of all organisms, and the unlikely sequences such as metamorphosis in the life cycles of some insects and other organisms. But this does not mean that these processes could not have happened by chance.
To resolve this it is necessary to consider what is meant by too complex and what is meant by chance.
All biological processes operate in accordance with the laws of nature, which are complex. Processes much simpler than the laws of nature also produce great complexity. Cellular automata can produce very complex patterns by repeatedly performing processes controlled by a few simple rules applied to about five or more simple components.
A very simple example of a cellular automaton is The Game of Life. It consists of an assembly of squares, a bit like an extended chessboard, on a computer screen or drawn on a sheet of paper. Most of the squares are empty and a few are filled in. Four simple rules determine how an arrangement of filled-in and empty squares leads to another arrangement, with some filled-in squares becoming empty and some empty squares becoming filled in. Such an arrangement may fizzle out after a few “generations”, or become static, or continue indefinitely. With more filled-in squares and a few more rules, the patterns can become very complex. The rules of nature are much more complex than this, he number of components (in this case, of organisms) is very much greater, and nature is three dimensional. That is why nature can produce such complex organisms.
The concept of something happening by chance means that it was unexpected, and/or unpredictable. Common examples are the toss of a properly balanced coin, and the many extremely unlikely coincidences that almost everyone can remember happening to them. Coincidences that may seem improbable happen in great profusion, just because there are so many opportunities during life.
The probability of some particular events, like the results of tossing coins, can often be fairly accurately calculated. The reliability of the calculation depends on how well the relevant details and circumstances are known and understood.
We often have intuitive ideas about the probabilities of unusual occurrences, but frequently get it quite wrong.
Creationists claim that there is a very high improbability for the process of evolution, quoting figures like one chance in many billions. Such improbabilities would be relevant to a process where all the components of a particular organ or organism somehow come together into their particular form in one single step. On this assumption, the eminent cosmologist Fred Hoyle indirectly described the concept of evolution as being like “a whirlwind in junk yard creating a Boeing 747”.
This is the antithesis of evolution. In evolution, at each of very many steps, the actual outcome was just one of many chance alternatives. Evolution is like the repeated processes described by chaos theory. Sometimes a very small change will result in much larger outcome, and sometimes a large change can have a negligible effect.
With large numbers of organisms continually reproducing prolifically in a changing and chemically reactive environment, very many significant interactions keep occurring, inducing heritable mutations, in very many individuals. Continual mutations to DNA make it very probable that some members of successive generations will be able to survive and prosper whenever their environments change.
The great range of environments on Earth, changing from place to place and from time to time, continually provides opportunities for the diversifications to develop into new species. Each generation has to struggle to reach maturity, amplifying the mutations. Chance makes evolution eminently feasible. There was no plan. Each individual organism is different, but the details of all of its characteristics were just matters of chance.
Claims by creationists about what evolutionists think about various aspects of science
The documents given out at the lecture to the Agnostics Group included the claim that evolutionists think that there is a “trend towards order”. Of course, as evolutionists and others are well aware, disorder is the predominate trend in the universe. Evolutionists know that there is also another kind of trend. This results from differences in the degrees of disorder, and differences of energy levels, which allows the occurrences of increased order, such as the development, or of the evolution, of stars, planets, life, and the changing stages of the weather, all of which are of limited duration. All of these will continue to come and go for a very long time.
Another claim was that evolutionists think that “spontaneous generation of life is probable”.
The probability that life emerges from inanimate matter rests partly on the probability of designed creation, which is the other alternative. Evolutionists think that the confirmed observations of life, and its history, show that the idea of divine creation of life and of life forms has some questionable issues. There are flaws in the structural arrangements of the bodies of various species, including humans. These arise from adaptations that gave advantages and were workable, but would have worked better if they had been designed. Evolution is essentially a succession of chance events, with no objective aim, and it just has to make do with whatever this produces. A creator, divine or otherwise, would have done better.
Other issues are the continual extinctions of species and the continuing emergence of new species, the incidental birth defects and inherited conditions in humans and other species, the cruelty of the food chain, and the darker aspects of human behaviour. Some of these aspects of life on Earth would not sit comfortably with some peoples’ concepts of the omniscient creator.
As for spontaneity, some evolutionists think the emergence of life from inanimate matter is likely wherever the environmental conditions allow it. Others think the emergence of life is possible, but suitable conditions for it are rare. Those who have studied the possibilities on Earth have concluded that it must have required a series of very unlikely coincidences. There is no plausible suggested series of stages that would explain how life emerged on Earth.
So evolutionists think that the generation of life is possible, but have various opinions on how spontaneous the process might be.
Another claim was that evolutionists think that there is a “life-matter continuum”. This term implies that, in addition to inanimate and living matter, there are conditions where something is partly inanimate and partly alive. This would be referring to some process that might have led to the very first form of life on Earth. Evolutionists assume there must have been such a process. It would have included a stage where inanimate matter would have become marginally alive, with the previous stage being almost alive. That is the only thing that can be said about the origin of life on Earth until there is a demonstrably realistic description of how it happened. So the creationist’s claim is correct, although most evolutionists might not have thought of it in this way.
It was also said that evolutionists think that the laws of nature evolve. What scientists call laws are only explanations of what they have progressively discovered. So these laws do evolve as new discoveries and new theories occur. But the fundamental processes of the universe have been operating long before they were discovered by human beings, otherwise no one would have been here to discover them.
Conclusion
That was my slant on this issue.
Continually challenging the validity of scientific observations and their theoretical explanations is an essential aspect of science. So creationists are entitled to challenge evolution, and it is not surprising that they do. But each challenge should similarly be challenged.
I acknowledge that science is incomplete. I acknowledge that science, including the theory of evolution, while not being the absolute truth, is the closest we have got so far. I can understand the creationists’ wishes to find a scientific justification for their beliefs.
But I think that evolution is compatible with the rest of science, and is the only explanation that fits the observed facts, and although there are unsolved problems, I think there are no plausible contradictions to it.
I invite you to pick holes in both sides of the argument.
o0o