I stopped by the Freethinkers table at my school’s activity fair recently. They had a number of tracts on their table. When I spotted one on Evolution, I picked it up. I’ve been writing about evolution for a while and tracts are quick to read. The title: “Evolution in a Nutshell”.
It was a quick read. It was mostly a theoretical explanation of the theory of evolution. It first explained artificial selection, then explained Natural selection and Niches – all things that should be reasonable simple and uncontroversial (at least at the basic level). Then, it proceeded to contrast micro and macro evolution.
Some critics of evolution assert that this only describes “micro-evolution”. They say that “macro-evolution”, where creatures change to form a new “kind” has never been observed. This is like saying that 1 + 1 may equal 2, but no one has ever counted to a million, so it is impossible to get to a million by starting at 1. Or, I can walk to the corner store, but it is impossible to walk across the country.
The answer is the same in each case is the same. Yes you can. All you need is enough time.
Look at ladder A on the right of the page. Can you climb to the top of the first ladder? Of course. You can climb to the first rung, from the first rung, you can climb to the second, and then to the third and so on. Can you climb to the top of ladder B? Not unless you have extremely long legs. You can climb to the fourth rung, but that’s as far as you get. What then would you say to the writer of the above paragraph when he says
That’s like saying 1 + 1 = 2, but you can’t count from 1 to a million. Yes, you can. All you need is enough time.
Obviously, that person is missing one crucial fact. You don’t need just time to get to a million, you need a path. The reason you can get from 1 to a million is that from any point, you can always add 1 and get to the next number. The reason you can climb to the top of ladder A is that from any one rung, you can always get to the next rung. The reason you can’t climb to the top of ladder B is that there is no path to the top that you can take.
Why am I picking on this one inaccuracy? Because natural selection is the only evidence presented for Evolution in the text. Furthermore, the text asserts that Evolution isn’t blind chance, or random because natural selection isn’t random. They practically argue against the idea that mutations are necessary in the Darwinian theory of evolution. So, their case stands or falls on the efficacy of natural selection. In the tradition of encouraging knowledge and fighting ignorance, I felt obliged to point out their error. OK, you got me. I hate missing a chance to tell someone how wrong they are.
Why are Mutations Necessary?
Point 1: Natural selection, as the term implies, works by selecting from things that are already present. For instance, if you have a basket of fruit, you can select from them based on color, type of fruit, weight, etc. But if there is nothing in the basket, or all the fruits have the same characteristics, selection (natural or artificial) is useless.
Point 2: natural selection works by eliminating characteristics from the pool. Imagine a basket containing red apples, green apples, carrots, bananas, oranges and grapes. Let these be my species. Now, I am the representing the forces of nature, selecting members of a species (fruit from the basket). Any fruit that I like, I eat. Those I hate remain.
Stage 1: I like fruits that aren’t roughly spherical. So, I’m going to eat them out of the basket. This gets rid of the carrots and bananas.
Stage 2: I like fruits that are cool in color, so I eat the grapes and green apples.
Stage 3: I like fruits that are not red, so I eat all the fruits except the red apples.
At this point, I have little to select. I can select the apples based on weight and such, but due to the homogeneous nature of my fruits, I’m not going to get any basket different from what I have. This is what is called a limit to natural selection. It is like the fourth rung on ladder B in the example above. There is no where to go from there.
Point 3: Natural selection produces a mostly homogeneous collection of a species. See point 2. Also note the increasing uniformity in the picture on the right.
Point 4: Natural selection often makes species less likely to survive when their environment changes. How do I know this? Imagine my sister shows us and she likes only sugary fruits. Having lost the variety of fruits in my basket, how many of them would she eat? A lot. Imagine my brother then shows up and he loves apples. I now have a total of zero fruits in my basket. Note that if the forces of natural selection (aka me) had not done the selection, my sister would have eaten everything except the green apples, carrots, and bananas. My brother would have eaten only the green apples, and my species wouldn’t be extinct.
The larger the variety in the species, the more resilient it is. The more natural selection that occurs, the less resilient it is.
Natural selection does not create diversity. It depends on diversity being already present. It does not preserve or increase this diversity; it reduces it. It does not make a species more likely to survive. The loss in diversity it produces reduces the viability of the species. So, how exactly does such a process create a progression of species from less complex to more complex and from less diversity to more diversity as the Darwinian theory of evolution requires?
It doesn’t. Mutation does. Mutation is what changes the genetic structure of a species. Mutation can create diversity. Mutation can lead to a more complex species arising from a less complex one. But (and here’s the rub), mutations are the thing that make evolution very improbable and reliant on chance. Don’t take it from me. Take it from this online pro-evolution textbook.
The Secular Student Alliance should not have published that tract.
- The Eclipse of Darwinism (atheonomy.wordpress.com)
- Seminar: Natural Selection and Evolution: Lessons from butterfly mimicry (Friday 1 February, 4 PM, LT 20) (rafflesmuseum.wordpress.com)
- Choice of Population and Mutation Frequencies (barelysifted.wordpress.com)
- Evolution in Theory (ferlans.wordpress.com)
- 10 Reasons Why Evolution is True (bioclaire13.blogspot.com)