The Theories Of Evolution

Lamarck
De Vries
Darwin

      Evolution, how do people think it happened? This is the question that this article seeks to address, as well as problems of these theories. 4 Main theories will be presented here: Lamarck's theory of the inheritance of acquired characteristics, De Vries’ mutation theory of evolution, Darwin’s theory of evolution by natural selection, and finally neo-Darwinism. Then, the time differences will be examined of gradualism versus punctuated equilibrium.

     Before we continue, the reader should understand that modern evolutionary theories are very sophisticated; likewise, that the article does not intend to encompass all of the specifics and technicalities of the many theories. The intent of this article is to provide an overview regarding the history of evolutionary theory, as well as a glimpse at modern evolutionary theory for anyone who may not be aware of precisely what evolutionary theory is. I would like to encourage curious readers to use this article as a starting point to search for more information about evolutionary theory. The author also writes from a young-earth creationist worldview, and I have accordingly scrutinized some of the theories with my own analysis.

      In 1809 Jean-Baptiste Lamarck published Philosophie zoologique. In this book he names a “First Law” stating that use or disuse of an organism’s structures causes it to become bigger or smaller. He also formulated a “Second Law” stating that all such changes were able to be passed down to offspring. Today Lamarck’s theory is often known as the theory of the inheritance of acquired characteristics

One example Lamarck provides for his theory are giraffes. He proposed that giraffes needed to reach higher leaves, so they stretched their necks. He suggests that the giraffes’ offspring would then have longer necks (1).

 

     Today most evolutionists disagree with this theory. People had little understanding of genetics at the time Lamarck proposed his theory, so they did not realize that an organism’s use or disuse of one of its structures would not affect the organism’s genetic material that would be passed down to its offspring. Someone with a scar would not have children with that scar because the scar would not make its way into the genetic material. Even if it did somehow make its way into the DNA of that person it would be somatic and not affect the gamete producing cells.

 

     In 1901 Hugo de Vries, a Dutch botanist, proposed his mutation theory of evolution (2). He formulated his theory after conducting experiments with the plant known as Evening Primrose (Oenothera Lamarckiana). He found that when he allowed the plants to self-pollinate, most of the resulting plants were similar to their parents but several were different. When he crossed these different plants the traits remained in the resulting generations. He thought that this must mean that because the traits in the different plants had not been in any of the parent plants that the traits must have been the result of mutations. The core of the theory he created was that mutations would suddenly and randomly occur anywhere in an organism and would immediately affect it. Lethal mutations are (for obvious reasons) not passed on, while both useful and harmful mutations remain. De Vries also stated that all mutations could be passed on.

 

     De Vries, unlike other secular scientists, proposed that instead of small changes that would gradually result in new types of organisms, new organisms would be formed in large steps, a process now known as saltation.

 

      De Vries’ theory has several problems. First, mutations do not occur nearly as often as De Vries thought. Second, he said that all mutations could be passed on, but today we know that only mutations occurring in the gamete producing cells or the gametes themselves can be passed down to offspring. In addition, many somatic mutations that occur in an organism do not affect it in any major way.  For example a mutation in the finger of the DNA for heart cells would not affect an organism.

 

     Another major problem is that mutations are usually neutral (that is, having little or no effect on the fitness of the organism) or are degenerative. Scientists have yet to show an example of a mutation that produced new genetic material that was helpful to an organism. In 1980 researchers began to purposefully mutate important genes of fruit flies. If they could have done this it would have been a big step in proving evolutionary theory. However, the only results were deformed fruit flies who could often not survive, even in a lab (3).

       

        Similar experiments have also been conducted on bacteria. Some biologists tracked bacteria for 20 years and 40,000 generations. They found only degenerative changes. If even this long amount of time could not produce any helpful changes, it is statistically impossible for mutations to occur in the large amounts necessary for De Vries’ theory to work!

     

       Charles Darwin went into medical school at the age of 16, but despised the atrocity of the methods of surgery and dropped out after two years, However, his interest for biology grew. He pursued a career as a clergyman and graduated. Darwin was not really interested in pursuing a career in the church. Ironically, Darwin had initially rejected biological evolution and Lamarck’s ideas. One of his former mentors was able to help him secure a spot on a mapping expedition. At the beginning of his voyage, he seems to have still believed in Biblical creationism.

 

      On this journey, Darwin visited the Galàpagos Islands, where he observed several species found nowhere else. Some of the most famous birds species he observed were finches. He observed that some of the finches on different islands had different characteristics for different environments. He also knew that all these finches had supposedly come from one species in South America.  He concluded that the birds characteristics must have branched out to adapt to their different environments. Darwin observed that individual birds had slight variations. He said that the individuals with the best variations would be more successful than the ones with inferior variations and therefore the superior would become more common. This process has become known as natural selection. Darwin is well known for publishing his findings in 1859 with his book On the Origin of Species. (4)

 

      Darwin’s theory is mostly correct on a small scale. Within a kind, there are variations and the best variations will do the best. On a larger scale though this theory starts to run into problems. Darwin correctly realizes that nature “selects” from already existing variation. This leaves the question: Where does new variation come from? Both creationists and evolutionists can agree on the fact that variations do occur within kinds of animals.

 

     The next theory we will discuss is known as "Neo-Darwinism." It is based off of Darwin’s theory, expanding on it by combining it with De Vries’ mutation theory. It states that mutations provide new genetic information slowly, and on a much smaller scale, than De Vries’ theory, and that natural selection selects the best mutations to be passed on. This combined theory still has many of the same scientific problems as the mutation theory of evolution. 

 

     One big question many people have is: Why do we not observe evolution happening? Some people turn to gradualism, saying that it happens way too slowly to observe, even in several people’s lifetimes. Others turn to punctuated equilibrium, the idea that at some points, evolution occurs very rapidly, while at other times very slowly, or not at all. There is no evidence for punctuated equilibrium, it is merely an attempt to solve the question of not observing evolution. On the other hand, it can be hard to produce evidence for gradualism. Many  evolutionary scientists now turn to the idea that changes that occur do not always have a direct impact on the fitness of an organism, but that neutral mutations, mutations that don't affect the organism in any significant way, drive evolution. 

 

     Ultimately, it takes a great deal of faith to accept the Theory of Evolution.

Nathan Krause, 2017
Sources-

1. Speer B. R., & Waggoner B. M. (n.d.). Jean-Baptiste Lamarck (1744-1829). Retrieved from http://www.ucmp.berkeley.edu/history/lamarck.html

 

2. S. S. (n.d.). Mutation theory: Mutation theory of evolution by Hugo De vries’. Retrieved from http://www.yourarticlelibrary.com/mutation/mutation-theory-mutation-theory-of-evolution-by-hugo-de-vries/12255/

 

3. Thomas B. (November, 2010). No fruit fly evolution even after 600 generations. Retrieved from http://www.icr.org/article/no-fruit-fly-evolution-even-after-600/

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Disclaimer: The views expressed in this article are those held by the author(s) and are not necessarily the views held by those who have reviewed or fact-checked the article and are not necessarily the reflective of the official stances of Creation v. Evolution Debate. This article is the property of Nathan Krause, and is displayed on Creation v. Evolution Debate with his permission

Comment On This Article-
3 Comments

Even most evolutionists don't believe in De Vries' mutation theory. They believe that the change from one animal to another is not from mutation, but from the genes actually changing themselves because of stress.

For example, you put fifty people in Alaska 5,000 years ago, the people that don't initially freeze to death will die and thus not pass that gene down to the generation. After about ten to twenty more years the children of the people who did not die will be born. If these children are to weak for the environment, unfortunately, they will die. repeat the process a few hundred times and you've got some pretty cold resistant people.

The same process can be done to get different results. For example, the domesticated red fox (https://en.wikipedia.org/wiki/Domesticated_red_fox ) was an experiment dedicated to figure out if traits other than the actual physical appearance of an animal can change over generations.

It isn't anti-christian to believe in evolution or the like (Genesis 2:7 (http://biblehub.com/genesis/2-7.htm), 1st Corinthians 15-47 (http://biblehub.com/1_corinthians/15-47.htm)). Even though early Christianity thought that the earth was literally at the center of the universe with everything orbiting it, was that found to be true?

Anonymous Fox-
J.E.S-
J.E.S-

Thank you for commenting, Anonymous Fox. I would agree that you could be a Christian and still be an evolutionist; however, I personally would not be comfortable with modifying the Biblical events and timescale to accommodate it. Along those lines, much more of scripture is harmed by evolutionary thinking than by heliocentric thinking ;)! If you wish to discuss this further, feel free to create a post/topic about it in the forum...

Nate-

It was never stated that De Vries' mutation theory is the commonly accepted theory. Both examples are best described as natural selection. The people with the genes that are cold-resistant will outlive the others. As to the domesticated fox experiment, Dmitry Belyayev (the founder of the experiment) himself was convinced that Mendelian genetics were responsible for the domestication of foxes. The fact that only the most tame were bred would naturally produce tame dogs. As stated in the given link, while the scientists were selecting based on tameness, tameness would be a result of hormones which would also affect the physical appearance of the animals.

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