James W. Grier column:

The role of accumulated changes in evolution

This is the original text submitted to the Forum newspaper for an article that they published 6/19/2005 under the published title of "Evolution's big changes are gradual" (a title which they chose but which I don't like because it potentially confuses the issue with other matters [gradualism, punctuated equilibrium, micro- and macroevolution] that are not a part of my article). The Forum also slightly condensed the article, because of space limitations, but published the bulk and major points of what I submitted. If you want the actual published version, it is available (for a charge) from the archives of In-Forum  (do a search, for all dates, for the terms: grier evolution). The following is my full article, plus a few [added segments in brackets, added with this web page 7/28/2006] in response to comments that I received from others after the publication of my article. JWG




A major missing piece in the endless (sigh!) debate on evolution versus creationism or "intelligent design" involves the role of ACCUMULATED small random events as opposed to a single big random event.

One of the arguments used against evolution is that one cannot have a random event that produces a complex end product, such as dropping a case of type on the floor and coming up with a Shakespearean play, having a monkey randomly typing at a computer and producing a book, or a tornado going through a junk yard and producing a 747 airplane. However, the theory of evolution does not claim that complex organisms originated that way. Rather, evolution involves big changes that arise from accumulated smaller changes. (How big and how small can vary and has been the source of much discussion among biologists, but the basic aspect of bigger resulting from accumulated smaller has not been a serious biological issue.)

An easy way to illustrate the cumulative effect of a long series of small random events is with the following simple exercise: (1) Start with several copies of the alphabet on a piece of paper (such as typing it out once on a computer and then copy-pasting it several more times until the page is full of copies). (2) Cut the page into the individual letters and put them into a box or hat. (3) Shake them all up and dump them on a table. (4) Place the closest ones next to each other so you have one long line of letters randomly arranged. The ones that are upside down, with the blank side up, can be used as blank spaces. (5) Choose a statement or sentence that you want to end up with, such as "The red fox jumped over the little brown dog." (6) Look for any parts of that sentence in the random line-up of letters (such as "i" and "t" next to each other as part of the word "little") and tape those pieces together. (7) Put everything, including the taped segments, back into the box,
shake it all up again, and repeat. Each time you repeat the process, add more letters to the taped segments as they are randomly encountered and fit parts of the sentence. You will eventually get your complete sentence. It is very much like a game of scrabble.

In the exercise above, the final sequence of letters was determined by a sentence that you chose [as well as the particular language and alphabet involved], thus, this case would involve "intelligent design [of humans]" but only in choosing what the outcome would be, not the process of arriving at it. The process itself was a simple accumulation ([in this analogy] by taping together) of a series of small random events. In the biological world, the present outcomes of living organisms are mostly shaped by natural forces including such things as the climate. Imagine, for example, that there is genetic variation among individuals of a kind of mammal in how much hair they have. If they are living in a cold climate, those with more hair will survive better and produce more offspring (with more hair) whereas in a warm climate, those with less hair will become more numerous. That small characteristic, whether they have more or less hair, is added or accumulated to all of the other hundreds of thousands of previous little characteristics that go to make up the complex animal. And those living in the north will become different from those living in the south. Enough differences add up to big differences such as among species. It is just like the accumulation of letters to make a word, words to make a complex sentence, and sentences to make a book or Shakespearean play.

In the case of evolution [of living organisms, where the genetic language/alphabet involves base pairs of DNA,] there is no "final product," only whatever happens to exist at any particular point in time. The outcomes are constantly changing as a result of continuing random events and evolution by accumulated changes. If you go back enough millions of years, there was a time with no mammals. At the present we have many different kinds of mammals, which resulted from accumulated changes from previous forms. Who knows what the next many millions of years will bring? As long as Earth remains suitable for life, the process will continue and the only thing for sure is that many of the animals then will be different from now as a result of the continuing process of accumulating changes!

So where does God fit into all of this? Well, it depends on whether God exists or not and whether you believe that he exists or not (which makes for a set of 4 possible combinations, e.g., he exists and you believe he does, etc.). God and the process of evolution as we understand it are not mutually exclusive. There is no reason why evolution cannot be the way that God created and continues to create different forms of life. I and other scientists have discussed this issue previously. I wrote about it, for example, in an article in the Forum in 1999. [If interested in that article and related discussion, click here (article) or here (web page with more discussion).]

Life is very complex and the theory of evolution on how life came about, evolved, and continues to evolve, is very complex. Evolution involves time and (the accumulation of) change on scales that most persons cannot easily comprehend. Evolution is easy to misunderstand or understand incompletely. An understanding and belief in evolution does not necessarily exclude God. One can believe in either or both God and evolution. I myself, for example, am both a professional biologist who believes strongly in evolution and a Christian who believes just as strongly in God as I understand him. I happen to even be the current president of a local, rural Lutheran congregation.

My view of God and how he works might differ considerably from the views of some other believers, but that is the very nature of religious beliefs and our personal journeys in faith and understanding. It was the whole basis of the Reformation during the 16th century. I'll tell others what I believe and they can take it or leave it. I'm not going to tell others what they must believe or think. And it's God's job, not mine, to judge them and their beliefs. In turn, I don't accept others implying that I'm not Christian if I don't believe exactly as they do, including on such matters as their interpretation of creation.

 


 

James W Grier
Last Updated: 7/28/2006
published by North Dakota State University