WELCOME TO
UNDERSTANDING EVOLUTION and SCIENCE
Welcome to the “Understanding Evolution and Science” homepage. There exist many web pages on the theory of evolution by a wide variety of people and organizations – scientists, humanists, atheists, agnostics, theists, fundamentalists, and many others. Many of these pages espouse a particular world-view or religious conviction, and often the scientific theory of evolution is intermixed with these world-views and philosophies, making the separation of theory from philosophy or opinion very difficult. Whereas many of these sites provide useful information on science and philosophy, I wanted to provide a resource that tried as much as possible to cut to the chase and present evolution succinctly and unfiltered.
The goal in creating this web page was thus two-fold. First, I wanted to provide a simple, straightforward presentation of the theory of evolution from a scientific viewpoint that could be understood by interested laypeople without having to wade through a FAQ question and answer site or decipher scientific jargon. Second, I wanted to create a site where interested individuals, students, educators, etc., could receive a skeletonized framework of the theory of evolution as a starting point to understanding more complex concepts and arguments that surround the theory, and how it applies to our daily lives.
WHAT THIS SITE IS NOT ABOUT
This site is not about changing anyone’s religion, viewpoint, or world-view, nor do I wish to debate the merits and/or pitfalls of anyone’s particular belief system – please do not e-mail or contact me to debate with you. I encourage you to keep an open mind as you read and think about the information presented at this site, but if you have already made up your mind, or if you disagree with the theory presented here, then I encourage you to use this site to understand what evolution and science are and are not – it can only help you to understand that which you may be opposed to. Also, I have tried as much as possible not to make this a creation vs. evolution site. Whereas I tackle some philosophical issues and common questions about religion and science in this document, you must search elsewhere if you are looking for “evidences” for and/or against evolutionary theory.
Many people have misconceptions about science, scientists, philosophy, and evolution. For example, some people fear that science has lead to social evils or injustices, or that acceptance of the theory of evolution has led to murder, crime, etc. Many people also fear the theory of evolution because they feel it somehow challenges their religious beliefs or that being a religious/spiritual person and accepting the theory of evolution is a contradiction.
Therefore, it comes as a surprise to some that many scientists are theists that have no trouble or internal conflict with accepting evolutionary theory while remaining spiritual, religious people. Some folks are also shocked to learn that theologians of all major faiths support modern science and the theory of evolution without conflict. Thus, one major misconception is an all-or-nothing view of science and religion – it doesn’t follow that just because you are a religious person that you cannot also accept the theory of evolution. It also doesn’t follow that if you do accept the theory of evolution as an explanation for biological diversity and human origins you will eventually become an atheist. How can this be so? I hope this web page will help you understand.
Most laypeople equate the word Darwinism with Evolution, and most people make no distinction between “Darwinism” and “Social Darwinism,” but the two are actually very different things. “Social Darwinism” is a naive philosophy of evolution used by rich and powerful men who wanted an excuse to justify child labor, slavery, ethnic cleansing, and euthanasia. But “Social Darwinism” and these horrific acts have nothing to do with science or the theory of evolution – it was just a way to make an excuse that sounded legitimate because it was supposedly “scientific.” Darwin never advocated any of these social ills. Whenever you see or hear about “Darwinism,” find out whether the person is talking about the theory of evolution or “Social Darwinism.” For this reason, I avoid using the word “Darwinism” because I feel it is very misleading.
So what are science and evolutionary theory really about?
Fact – a single piece of information. This is a sneaky word – most people associate the word “fact” with “truth.” But how do you know your fact is true? For instance, let’s say I grind up a mineral or organic matter, send it through a machine, and I get a number 57. Is 57 true? How do you know you put in the correct sample, for instance? I have found that “fact” is impossible to define and it is misleading: therefore, we will avoid talking about facts here.
Truth – this is also something that is near impossible to define. Many people think that science is somehow the search for ultimate truths, but it is not (see below). Therefore, we will avoid using “truth” as well in our discussion because it is both confusing and does not represent what scientists do.
Data – the bits of information scientists gather. These are not facts. Using the example I gave above for fact, the number 57 that your machine spits out is a piece of datum – whether it is a fact or true is difficult to know. I believe it is preferable to speak of data rather than facts when speaking about science, the scientific method, or evolution. Saying, “the data suggest …” seems closer to what we do as scientists than talking about “facts.”
I am sure most of you have encountered a staggering number of definitions for science. Some sources say something in a vague way about “science as a way of knowing” and that it relies on certain constructs, e.g., hypotheses, theories, etc. Other sources will say that there is no precise definition of science, but we know it through doing it! I have used a definition of science that I adapted from Dr. Ron Toth at Northern Illinois University, and in both non-major and major courses I have taught it seems to crystallize what science is and is not.
Q: What is Science?
A: Science is a very narrow discipline that seeks to pose answerable questions about the physical universe. In other words, science is a way of knowing about the physical universe that assumes the physical world can be explained through natural causes and effects.
We make three major assumptions as practicing scientists:
Be aware that philosophers and theologians, among others, sometimes debate these assumptions and what they mean. In science, however, we assume up front that a real physical world exists with observable, testable, and explainable properties. This is not to discount the very difficult and challenging ideas that philosophers, theologians, and others bring to our understanding of the human experience – just keep in mind that if we violate these assumptions we are no longer practicing science.
In science, any results you obtain should be repeatable by others. If other people – using the same tests, same set of controls, and same environment – do not get the same results, our results are called into question. If the tests and results we report cannot be repeated by others, we are not doing science.
We can never prove anything in science absolutely. Scientists only deal with PROBABILITY. Something in science might have a high probability of being correct, but we can never be 100% certain. Does this surprise you? Many people do not understand or appreciate this aspect of science. Reporting error or chance of error in results makes a study stronger in science, not weaker, because it tells other researchers how accurate the data are, and how much confidence can be placed in the results. Some people see uncertainty and debate over probability in science as a sign of weakness, perhaps because they like to deal in absolutes – you’re either right or wrong, good or bad, benevolent or evil. As scientists, we have to be willing to put up with some amount of uncertainty because we will never prove anything absolutely.
In science, you should approach every claim with skepticism and an open mind, including the theory of evolution. Please keep in mind that being skeptical is not the same as being cynical. Being cynical is closing your mind to all new ideas on the assumption that no new ideas or theories are worth accepting. Being this close-minded is very bad for science because it does not allow new discoveries to be made or reported. At the same time, we do not want to be so open-minded that our brains fall out of our heads, to paraphrase the late Carl Sagan. Healthy skepticism, combined with wonder and excitement, are important ingredients to doing science successfully.
You should be willing to put certain claims on hold until better evidence surfaces. For example, I think it would be awesome if there really were a Loch Ness monster (perhaps a prehistoric reptile from the Mesozoic Era) lurking in the depths of a fjord in Scotland. However, as a scientist, I have to have the patience to wait and see what the data tell me. So far, we have no good evidence that Nessie exists. Maybe she does, but as a scientist I have to put that idea on hold until better evidence surfaces – in this case quite literally.
Remember, as the late astronomer Carl Sagan once said, “Extraordinary claims require extraordinary evidence.”
The scientific method has been presented in many ways and in many forms. Usually, it is described as a system where a scientist observes a phenomenon, proposes a hypothesis to test it, designs an experiment to test the hypothesis, gathers more data, etc. In short, it is a rough approximation of what scientists do, but scientists do not follow a specific “recipe” for doing research. What I provide here are definitions of common terms associated with the traditional discussion of the scientific method with some examples. These definitions are based in part on my experience with these terms and discussions with other scientists, but some people may disagree with how I have expressed them here. However, I feel these definitions are simple and straightforward, and will therefore assist you in learning and understanding them. Please refer back to this section of the document often as you read the rest of this material to refresh your memory.
A generalization based on some data or idea that guides the early stages of research.
A scientific hypothesis has three properties:
Notice that a hypothesis can be formed based purely on an idea or even a dream. Scientists do not necessarily observe something and then go to test it. Many times scientists will have an imaginative thought or vivid dream that sparks some interest and then leads to construction of a hypothesis. As long as the hypothesis is testable, falsifiable, and predicts certain outcomes, it doesn’t necessarily matter how the hypothesis came about in the first place.
A constant phenomenon or process.
As with a hypothesis, a scientific law has three properties:
Notice here that a scientific law is not some all-powerful proven fact as many people believe. A scientific law merely describes a constant phenomenon or process that can be tested, falsified, and predict certain outcomes.
Some familiar examples:
The Law of Gravity (Physics) – on Earth, an object of any mass will fall (accelerate) towards the ground at 9.81 m/s2
The Law of Superposition (Geology) – in rock layers, rocks on the bottom are older than rocks on the top
The Cell Law (Biology) – all living things are made of cells
Genetic Law (Biology – unfortunately sometimes called Genetic “Dogma”) – DNA à RNA à Protein synthesis
An over arching generalization that explains and makes sense of laws, hypotheses, and observations.
As with hypotheses and laws:
In addition, a theory has EXPLANATORY power. In this sense, theories are the most important concept in science because they unite and explain apparently unrelated phenomena.
To drive home what a law and theory are, and how science works in general, I present here a brief overview of the atomic theory and the chemical laws.
Over a period of time, scientists like Bohr, Rutherford, and others put together an idea. Matter is made of atoms with positive centers of neutrons and protons surrounded by a cloud of negatively charged electrons. This idea (the Atomic Theory) explains the chemical laws. For example, a whole bunch of one type of atom is a pure substance. Pure substances combine only in certain ratios due to how many electrons they can share, donate, or receive. Aha! Heat is the motion of atoms. As the gas molecules hit the sides of a container, they exert kinetic energy and push on it. And so on. The Atomic Theory gives us an EXPLANATION for why these things happen.
The Atomic Theory Explains the Laws of Chemistry
Whether atoms exist or are “facts” is irrelevant. The atom is a concept created to explain what is observed. No one will ever see an atom, or weigh it, directly. Electron microscopes make pictures that look like little bumps, but whether they really look this way is doubtful. Are atoms a “fact”? Most people would answer, “yes” even though there is no direct evidence. Believe it or not, whether atoms exist or do not exist is not important as far as the explanatory power of the Atomic Theory goes. “Facts” and “Truth” are not needed to do science. The Atomic Theory is a concept which makes sense out of the laws of chemistry, and it is powerful in this sense because its predictions can and have been successfully applied repeatedly by many people.
With the Atomic Theory framework in mind, now let us finally turn our attention to the theory of evolution. Let’s start how we did with the Atomic Theory and list some biological laws.
Again, so what? Life is hierarchical – there are groups within groups – why? All of life is cellular – why? Why would DNA be found in all living cells? Why should the genetic code be universal?
While you think about those questions, here are some others to ponder.
What “idea” or concept explains these observations as well as many others? The Theory of Evolution.
Q: What is the Theory of Evolution?
A: All life has descended with modification from a common ancestor.
Put another way, cellular life evolved once, long ago, by natural methods and all organisms alive today, as well as those contained in the fossil record, are descendents of this single common ancestor. The simple phrase, “there has been descent with modification,” says it all. The Theory of Evolution predicts that we are all related and that we all share a common ancestor.
The Theory of Evolution answers the questions and explains the laws described above:
IS EVOLUTION A FACT OR A THEORY?
According to what we have outlined here, it would be incorrect to call the Theory of Evolution a fact. Again, the Theory of Evolution states that there has been descent with modification from a common ancestor. However, some scientists and evolution websites suggest that Evolution is a fact, but the mechanisms of how evolution occurs are the theory. This seems a bit confusing to most people.
I believe what these scientists are trying to say is that there is very strong evidence that organisms have changed over time – for instance, no matter how old or young you may suspect the Earth is, we can follow sequences of the rock record all over the world and see that some organisms disappear, some new organisms appear, and some appear to be transitional as you go from older rocks to younger rocks. This observation has been made by many people and offers strong evidence for change over time. It seems that these scientists and evolution websites are calling change over time “evolution,” and this term is sometimes applied to changes in the universe, our planet, etc. However, change over time is not the Theory of Evolution.
And although we have strong evidence from many fields of science that there has been descent with modification from a common ancestor, we will never prove evolution absolutely. Evolution is a theory, not data or a fact, and its predictions are supported from many branches of science – geology, paleontology, biology, chemistry, physics, etc. For example, a unique, sequential fossil record in which both transitional forms and changes in fossil organisms show variation on a common body plan is evidence that supports the explanation that all organisms are descendants of a common ancestor.
By the same token, Natural Selection is often called a theory that supports the fact of evolution. Although many scientists and sources refer to Natural Selection as a theory, I would argue that Natural Selection is actually a scientific law.
Natural Selection – all populations vary, all populations produce more offspring than can survive, and individuals within populations with traits that allow them to successfully mate and reproduce viable offspring will be selected for. This is a constant phenomenon, occurring on a daily basis, and even most die-hard fundamentalists accept that Natural Selection occurs. Therefore, Natural Selection would be, by the definitions presented here, a biological law, not a theory. It does, however, provide a mechanism for how descent with modification from a common ancestor may occur, and thus provides more evidence for the theory of evolution.
Natural Selection has unfortunately been called “Survival of the Fittest,” but that is not what Natural Selection is about – sometimes organisms with a particular trait end up surviving by happenstance. For example, in a population of insects sprayed with an insecticide, some insects by a random genetic mutation possess a gene that gives them resistance to the insecticide – because these individuals end up being the survivors, but not necessarily “the fittest,” they pass on their genes to the next generation.
Getting back to evolution as a fact or theory, I would suggest that this is a sidetracking issue. The Laws of Biology are well documented. Descent with modification from a common ancestor explains them. That is all that is necessary. It is the same for the Atomic Theory. A theory is not a fact – it is an explanation. It is not necessary to prove that atoms exist for the Atomic Theory to have explanatory power, and the same goes for evolution. Descent with modification from a common ancestor explains it all.
I have stated previously a definition of science, and the basic assumptions scientists work under. If you have more questions or time, here are some philosophical issues to think about.
DO SCIENTISTS IGNORE THE SUPERNATURAL BECAUSE THEY DISLIKE IT?
NO. Scientists cannot deal with the supernatural because that is not what scientists do. Science assumes naturalism, a series of cause and effect relationships. For example, if an experiment cannot be conducted to gather data to disprove a question, then there is no scientific question. Scientists practice methodological naturalism – as a working scientist, you assume there is a real physical world outside of your body that has laws and properties which can be observed, understood, and tested. Scientists cannot deal with the supernatural because, by its very definition, it is “beyond nature.” Nobody can test or falsify the existence of God; you cannot weigh God, touch God, feel God, see God, etc., in the physical senses of these words. It does not follow that there is no God, just that, as a working scientist, that is something you cannot do.
DOES ACCEPTING THE THEORY OF EVOLUTION LEAD TO ATHEISM?
NO. Some people allow methodological naturalism to be carried over into a philosophy about the nature and purpose of the universe. If you believe that all things can be explained by cause and effect relationships, and if you assume that all there really is in the universe is matter and energy, you are practicing philosophical naturalism, which some people label Atheism. But the two systems ARE NOT INTERCONNECTED. Some scientists make this mistake – they combine their methodological naturalism with their belief system, and fail to see the difference between the two. Many scientists, who accept the theory of evolution, are devout Christians, Muslims, Hindus, etc. They practice methodological naturalism at work, but in their private lives have many different philosophical and religious views, and have no internal or external conflict with this. Something to keep in mind is that just because life may have evolved, and just because we may have evolved from primates, does not mean there is no God, or no values or morals, etc.
WHY DON’T SCIENTISTS ACCEPT CREATION “SCIENTIST” / INTELLIGENT DESIGN THEORIST (IDT) EXPLANATIONS?
Creation “Scientists” and Intelligent Design Theorists want to do something with science that it was not meant to do – they want to use it to test and prove the existence of supernatural forces and/or beings. They assume that there are supernatural forces that influence matter and energy, and that miracles can be invoked to explain some or all events. But science is not practiced based on faith, or by invoking a miracles and/or a creator every time we run up against something we cannot understand or explain. Because many people do not understand this, when Creation “Scientists” or Intelligent Design Theorists complain that science is loaded against supernatural explanations it sounds like scientists are going out of their way to block another competing idea or theory. But Creationists and Intelligent Design Theorists do not have a testable, falsifiable hypothesis or theory with predictive powers – instead, they begin with the assumption that the unexplainable must be miraculous. Some Creation “Scientists” even take an oath that says, in effect, “they will prove the truth of the scriptures.” Saying “God did it,” doesn’t help us explain and/or extract useful information as scientists, doesn’t help us test anything as scientists, and prevents scientific progress. God may well have done it, but since God, his/her/its thoughts or plans, and anything supernatural is beyond the bounds of what scientists do and what humans living in the physical world can test, these people are attempting to replace the scientific method with a faith system.
SCIENCE – THE AUTO MECHANIC ANALOGY
This analogy is adapted from Eugenie Scott at the National Center for Science Education. One way to explain the narrowness of science is by comparing it to auto mechanics. An auto mechanic assumes methodological naturalism. He/she assumes a priori that there is a reason based in the physical universe as to why your car runs or does not run. Let’s say you were out late one night having an affair with someone you weren’t married to. The next morning, your car won’t start. It could be that a god was punishing you for sinning, but when you have the car towed to the mechanic, he/she is not allowed to assume that. They will look for a physical cause (i.e., low battery voltage) for why the car does not run. He/she cannot prove or disprove that a miracle made the car stop, or that the gods exist or do not exist or are angry with you. It is not within his/her narrow discipline of auto mechanics. You would not pay for a diagnosis such as, “Sorry, the battery died because you sinned.” This example may sound silly or exaggerated, but people accept the limits of auto mechanics to a cause and effect sequence of events firmly grounded in the laws of chemistry (combustion) and physics (brakes), and yet expect so much more from science.
WHY NOT GIVE EQUAL TIME TO CREATION “SCIENCE” OR IDT IN THE PUBLIC SCHOOL CLASSROOM AND SCIENCE EDUCATION?
If Creation “Science” or Intelligent Design Theory (IDT) were really proposing testable, falsifiable, and predictive hypotheses, laws, or theories we could all evaluate, it would, of course, be unfair to prevent their scientific principles from being discussed and taught. However, they are not giving us anything scientific – instead, they wish us to insert their particular religious beliefs and values into a scientific discussion.
You may be faced with this question at a school board meeting in your town at some point. The best way you can diffuse such an argument is not to defend evolution, but to ask school board members or members of the public proposing such “equal time” legislation whose creator we will be discussing. Sometimes creationists or school board members may actually tell you they want something specific like Biblical Genesis taught side by side with evolution. Ask them if other religious origins should be discussed, to be fair to everyone. Many people do not recognize that we live in pluralistic society where all viewpoints and religious convictions are held – to be fair, we would have to recognize and discuss everyone’s religious origins story. But then, we wouldn’t be teaching science anymore. Suggest a comparative religions class or social science class would be an appropriate outlet for discussing various religious views, not a science classroom. Also point out that if we favor a Christian origins story, for instance, we are violating the First Amendment, which states that “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof …” If we allow one particular religious viewpoint to dominate a classroom to the exclusion of others, we are giving preferential treatment to that group, and preventing equal time and expression of other viewpoints and convictions.
IF SO MANY PEOPLE BELIEVE GOD CREATED SPECIES, WHY ARE WE TEACHING A MINORITY OPINION?
Theories in science are not opinions, are not voted on, do not win because of popularity, and are not used and discussed because they satisfy public opinion polls. Darwin’s Theory of Evolution was formulated using the scientific method, has been tested by many scientists, and explains many seemingly unrelated aspects of biology, paleontology, etc. Its power at explaining major aspects of the living world is why it is the cornerstone theory of biology, and why it is taught. Theories can be falsified, but the replacement theory must explain and account for all that the original theory did, plus explain new things that the old theory could not. So far, no scientific competing theory has been proposed or explains as much as evolution does. Simply saying evolution should not be taught or discussed because it upsets some people or does not fit with their particular world-views is not a scientific reason for dismissing it.
Many people misunderstand science and the Theory of Evolution because most of what they see around them and think is science is really technology. Rocket science is an oxymoron – we did not discover a single new physical law or theory by sending a rocket to the moon. We used Newtonian physics, the gas laws, etc., to design space ships, but it took imagination on the part of the scientists who were applying the laws of chemistry and physics to build the machines. These machines were inventions and creations, conceptually not any different than Beethoven using music theory and his imagination to create the 3rd Symphony.
Remember that science discovers generalizations about the universe such as the gas laws. If you heat a gas, it will expand. This knowledge has no moral value and is amoral. However, if you use the gas laws to build a gun or a stove, those inventions (technology) do have moral value. Science itself has no moral value; it is a narrow discipline that produces generalizations about the physical universe (i.e., how the universe and things in it work and why). Technology is applied science and has moral value. Technology uses the generalizations of science to make products and inventions that can be used for good or bad purposes.
Does this mean scientists are somehow “off the hook”? No, but neither is the general public. Scientists are human beings with their own hopes, wishes, beliefs, and morals, and scientists make moral judgments about technology and its application just like everyone else. Science itself is amoral – it only tells you what is possible. Scientists and the public are not amoral. Understanding what science is and is not is important in making decisions about technology, its use, and the implications of future research on everyone’s lives.
I hope this web page has been useful to your understanding of the theory of evolution and how science works. Perhaps you have a better understanding of what science and evolution are and are not, and can now apply this knowledge to other aspects of your life. Perhaps you may also now understand why scientists can be theists, why so many scientists accept the theory of evolution as an important concept that explains many diverse biological phenomena, and why religion and science are not at odds with one another.
Many people do not accept evolution ultimately because it predicts on strong evidence from the fossil record, comparative anatomy, genetics, and behavior that we share a common ancestor with chimpanzees. I realize that for many people this is a scary thought, and is perhaps the only reason they refuse to accept the theory of evolution in the first place. My purpose here is not to convince you otherwise, only to provide information on how science and evolution work. If you’re interested, I suggest considering the following concepts and ideas stated throughout this document one more time:
Science does not lead to atheism or immorality.
Many scientists are theists.
Theologians of all major faiths support modern science.
Even though humans may share a common ancestor with chimpanzees, we still have value.
Even though humans may share a common ancestor with chimpanzees, there can still be a God.
Even though humans may share a common ancestor with chimpanzees, there can still be morality.
Even though humans may share a common ancestor with chimpanzees, people can still love and be loved.
Sincerely,
Dr. Matthew Bonnan
I wish to acknowledge Dr. Ron Toth of Northern Illinois University for inspiring some of the information presented here and for many fruitful discussions about science and evolution during my graduate studies at NIU. Any errors are the fault of the author of this site alone.
Three Intelligent Design Theorists present arguments for IDT, and three proponents of evolutionary theory respond. I highly recommend visiting this site and reading it – gives an excellent overview.
Suggestions for this web page?