Convincing Nay-sayers of Evolution?

2007 Oct 25

A guy on the internet by the name of Rob has written a piece suggesting a means of convincing people of the veracity of Darwinian evolution (evolution as the explanation for the origin of species). He used the illustration of three modern systems that function surprisingly well. He thought they each had similarity in operation to Darwinian evolution. The mechanism for the success of these systems has been hard for people to grasp. Likewise he thought that because people have found the mechanism of Darwinian evolution hard to understand, maybe that was why they rejected it. Therefore these systems might be used as teaching cases to convince people toward Darwin.


The first system is Wikipedia. Wikipedia is somewhat controversial because many people find it hard to trust as a source of authoritative information. Since anybody on the internet can change its contents, how could it be reliable? And yet at least one study showed it to have accuracy similar to Encyclopedia Britannica.

Rob suggested that each edit to Wikipedia might be compared to a Darwinian genetic mutation. He acknowledged that biological mutations are generally bad. He did not suggest that most edits to Wikipedia are bad. I have contributed to Wikipedia (as Lgrove: 1, 2, 3, 4 and others) and I believe that most edits are good, or at worst benign. As evidence, check out the history on most any article. Therefore, Wikipedia (which flourishes only in an environment of beneficial new information) is not an example of evolution at all.

As an alternative argument to make my point, check out a Wikipedia topic such as Islam; it can't be edited because the administrators of Wikipedia have protected it from vandalism. Most of the mutations were degrading, so they stopped the "evolution" of the topic artificially. This argues that Darwinian-style improvement is non-functional when most mutations are bad. (And in the biological world, overwhelmingly most mutations are bad.) On Wikipedia, improvement continues only because an alternative process is used: consensus via administrators that regulate the changes. This process is a form of Intelligent Design.

Rob did not consider these aspects in his article, but said that natural selection handled any issues from mutations. He attributed the quality of Wikipedia to the effectiveness of (natural) selection to weed out the bad edits. Since every reader is a potential editor, even if they think they couldn't improve an article, he considered that an approval (a positive) selection. This could be considered to be similar to an organism getting to live another day.

However, there is also negative selection, and that starts to show a breakdown of this analogy. In biological evolution, this would be the death of an un-fit organism. In Wikipedia it is unclear if the analogous action is a deletion of words or the deletion of the topic.

However, I think an even more interesting question is: What is the evolutionary selection test?

Believability problems

In Wikipedia, we have assumed that the selection is directed toward improvement of quality ("Does making this change better explain this topic?"). In biology, the test is not directed. (It is "Does the organism survive?"). They have some similarity, but they are actually very different.

In Wikipedia, selection is based primarily on the merits of the content. Good edits usually live. By contrast, in biology the selection is only weakly related to the merits of the content. Rather than survive by their mutational improvement, organisms are more likely to fail by some unrelated random chance. The success of the Darwinian evolution concept, however, crucially depends on reliable preservation of individuals with the fittest genetic improvements. This is especially critical because improvements are so rare. Biology is unlike Wikipedia because few of the rare improvements are retained.

We have observed selection for thousands of years - consider two aspects of selection in the context of dog breeding.

The biological reality of natural selection is that its grand statistical process winnows out the unfit. If domesticated dogs are left to go feral in an ordinary environment, their characteristics become common and undistinguished. This shows that the fittest are those those most like an average canine. Natural selection preserves the status quo.

Also consider human breeding of dogs. It shows us that selection processes narrow down existing genetic information. (Breeds are still dogs, but with less genetic richness.) Like selection by humans, natural selection (especially in unique environments) also reduces genetic richness.

Consider that the rate of biological change for the worse is vastly greater than the rate of change for the better. Natural selection gets rid of these defects. But the side effect is that the species also looses some genetic diversity. This diversity is critical to adaptive survival - so the species as a whole becomes weaker. This is absolutely the opposite of Darwinian evolution (i.e. increased life competency and diversity).

Finally consider that extinction of organisms is well-known from our lifetime back through pre-history. And, introduction of a major new organism (e.g. wolves) has never been observed. Such introductions are explained by Darwinian evolution to have happened only at unimaginably distant dates in pre-history. Therefore by observation, it would seem that natural selection is killing off organisms that are un-fit to adapt at a rate faster than they can evolve. At such a rate, evolution can't seem to even explain our continued existence. If I accept the time-scales of evolution, we should already have become extinct!

Other systems

The thrust of Rob's article is to convince people of the effectiveness of (some) simple processes to produce focussed good information in the presence of sloppy, noisy, low precision data. The latter two systems (Prediction Markets and a recommendation system for movies like that used by Netflix) do this surprisingly well. Although these systems may not be intuitive to many, I will concede his point. However, these two example systems do not make the case for Darwinian evolution! The second system has a high flow of new information coming into it - which biological genetics does not. The third system starts with a data set and merely organizes it without changing it.

Evolution never argues that its processes organize biological information, so these systems are very unlike evolution. All that these might be able to argue is that the simple process of natural selection can be very effective in removing genetic defects. I can agree with this. Biology does not have a good flow of new information coming into it. So without new and beneficial information, there is nothing to select toward improvement of a species (i.e. increased fitness). This is the great problem of Darwinian evolution.


In Rob's conclusions, he notes that there are probably few atheists that reject evolution. He also acknowledges it is probably because they have no alternative explanation for life - even though Darwinian evolution might be mentally challenging to them.

On the other hand, why do people with (usually religious) alternative explanations for life have such a difficulty with Darwinian evolution? Probably because what we observe and can test includes substantial evidence against evolution.