ENTRY 9 Mutation Theory of Evolution

In this entry, we will discuss the mutation theory of evolution and also explain the basics of what science knows for sure about mutations. I know many times when the subject of mutations comes up, many people have flashbacks to Hollywood movies like “The Fly” or “Godzilla” or even “Spiderman” – all of these sci-fi movies show off how perfectly wonderful or horrifying mutations can be! I will admit, if I could mutate myself some Spiderman like abilities, I wouldn’t be too upset. Yet, knowing my luck, I wouldn’t get the ability to shoot webs out of my hands for a fast get-away, instead I’d likely form an exorbitant number of eyeballs all over my head and scare small children every time I tried to go to Walmart.

But let’s dive in, shall we?

MUTATION THEORY OF EVOLUTION

During the 1900s, scientists were discovering the modern knowledge of genetics. Gregor Mendel’s writings had been rediscovered and scientists were learning a lot from his pea plant experiments. One such scientist was Hugo De Vries. According to De Vries, new species are not formed by continuous variations (such as what Darwin proposed in natural selection) but by the sudden appearance of variations which he named mutations. Therefore, if biological evolution is to take place, mutations must form new genes.

However, getting a gene mutation to occur that would present a new structure on an organism is a little bit complicated. A single mutation may alter a gene, but these simple mutations often go undetected, therefore, they wouldn’t produce a new characteristic or trait like an extra pair of eyes or a different kind of leaf on a plant. Most noticeable changes require the interaction of many genes. Changes that genes may need to go through to produce a TOTALLY different structure would require HUNDREDS of mutations. This notion here is why evolution requires so many years to take place.

MUTATION-SELECTION THEORY

Today, most scientists agree that natural selection (proposed by Darwin) by itself does not explain how evolution could have taken place. Many believe in the mutation-selection theory or Neo-Darwinism theory which combines DeVries and Darwin’s two theories. There are three main points to this theory:

1. Mutations supply new traits

2. Organisms produce more offspring

3. Selection allows only those with the best traits to survive

Now, to be honest, this theory makes a lot of sense until you do a little digging into what mutations actually create. If we could assume that mutations produced good things like an extra set of hands (what mom hasn’t dreamed of this?) or another set of ears (yet again, a mother’s dream!) then please, by all means, bring on the mutations! However, what we find in real life is that mutations typically have a negative effect if they occur at all (because mutations are by nature, rare) and are noticeable. If they are harmless, then sometimes, we don’t even know we have the mutation.

Let me explain more…

For many years, scientists have been conducting experiments on fruit flies. They have short lifespans so they make a great subject to study how the different generations of fruit flies pass down traits. Scientists have exposed the poor little dears to x-rays, chemicals, high voltage electricity and the likes to see what types of mutations might occur. Fortunately for scientists, mutations abound! Unfortunately, the mutations never caused an evolution of a new creature or even improved the fly’s characteristics/lifestyle. In all the experiments, the mutations were harmful to the fly. Most made the fly blind or flightless and here’s the kicker…no other normal flies wanted anything to do with the mutated flies.

It is kinda hard to reproduce a mutation when you are being exiled by your other fly peers…but such is always the case for the poor mutated fruit fly.

But surely that isn’t so, you say. Isn’t there a famous Four-Winged Fruit Fly that is paraded on most high school biology books? Why yes, there is a famous fly – Four-winged-Fred as I so lovingly refer to him. Let’s talk about him!

Four-winged Fred is an example of a mutation that many evolutionists like to hang their hat on. And, he does show up on the covers of textbooks or in many graphics promoting evolution. But here’s the problem with poor Fred, he can’t fly. He’s more of a “sit” than a fly….okay, bad science humor. However, that is the problem with Fred. He is mutated and he does have four wings, but he can’t fly and when put in a cage with other normal flies, they won’t spend any time with him. So, in the end, he’s still a fly, just a mutated one that no one likes.

And that is part of the problem with mutations in nature, they don’t tend to survive because one, the very features they are supposed to use to survive fail them so they typically die a young death. And two, the other creatures in their species find them weird so they don’t mate with them to pass down any of their traits however weird and cumbersome those traits might be. Again, survival of the fittest takes over to rid the world of the problem species and only keeps the good ones. Unfortunately, Mother Nature is not a politically correct activist -- if you’re weird or handicapped, you’re out.

And here’s one last tid-bit about Fred….though he was created and did live, the only time a four-winged fruit fly ever existed was in a lab environment. This hasn’t occurred naturally. And, the only reason Fred might have lived as long as he did was again, because he was created in a lab. One day of living in the wild being a four-winged fly who couldn’t fly would have meant frog-meat for Fred.

So, let’s talk more about mutations specifically not just their examples. The actual definition of the word mutation is any change to an organism’s genetic material. Herein lies the problem, changing an organism’s genetic material is almost always harmful to the organism. It can cause a variety of disorders, and many mutations can even cause death or a shorter life-expectancy. Plus, as stated with Fred, mutated organisms are rarely received by other species to mate. No place in nature do we ever see mutations as a positive.

Let me ask you this, unless we are talking about a Marvel comic, when have you used the word “mutation” and thought good thoughts? You don’t. The reason you don’t is because mutations by and large are bad.

Here’s a little more info on mutations. There are two main types, somatic and germ mutations. Let’s start with somatic mutations. A somatic mutation can occur in any cell in the body. A good example of a somatic mutation is cancer. Not all somatic mutations are cancer, however, this example shows how cells can become mutated and become cancerous but then are not genetically passed down to offspring. Even just a slight skin alteration can be a somatic mutation. Here again, a somatic mutation isn’t normal, it isn’t wanted, but it also isn’t passed down to the offspring.

Germ mutations are different. These are mutations that occur within the organism’s DNA and CAN BE passed down to future generations. Gene mutations though are typically very bad. Cystic fibrosis is an example of a germ mutation that is passed down through generations. Cystic fibrosis is a genetic disease that causes persistent lung infections and limits the person’s ability to breathe. The median age of death for someone with CF is around 30 years.

So again, if you have a mutation that isn’t that bad, it is typically a somatic mutation and not the type that can be passed on to the next generation. If you have a germ mutation which can be passed down to future generations, it is usually a harmful disease which shortens the life of the organisms involved.

When we pair what we know about mutations and the Mutation-Evolutionary theory then all its hopes and dreams are dissolved. IF the mutations were good and IF the mutations could be passed down, then maybe this would work, but that isn’t what we find in science or in nature. Mutations are generally bad, if they are passed down they kill early, and in any and all mutated situations, the organism with the mutation is shunned by others around it. Therefore, this theory makes it pretty hard to create a new kind of organism.