Information Vs Variation

Information can never increase according to creationists. What they do not consider is that information is not the real issue. Variation is. Darwin noticed that all creatures vary, and that if the variation was hereditable then evolution occurs.

An important first question is "what evolves, a species or an individual?" This is important because when considering whether information gain is a barrier to evolution, we must know what we are measuring information gain / loss (or variation) in. Obviously species evolve, not individuals, so when considering information or variation we should consider the population, not the individual.

I will look at the way that domestic dogs have been artificially selected from the grey wolf. This is not controversial, and will be a readily known animal for the purposes of this study. It is also an example that highlights excellently the points I wish to make. I will concentrate on one particular detail, the leg length.

In the grey wolf there is a variation in the leg length. The variation between the shortest leg length and the longest is not very great, and most wolves appear in the middle. This can be shown graphically by a 'bell curve showing the number of wolves against the leg length:

Artificial selection has increased the variation in leg length amongst the descendants of the grey wolf. We have Chihuahua's and Great Danes that show how much the leg length has altered. This leads to a much wider leg length variation, and hence the bell curve for the domestic dog looks like this:

These are the descendants of the grey wolves, and so any new variation in leg length, if not in the original population must be in addition to the variation in that population. This is evolution in action.

Where has that variation come from? It is not in the original population, as can be seen from any study of wolves, therefore it must have come from something new.

A common objection to this argument is that the information was already in the wolf genome. This is countered by pointing out that there are many mutations in the domestic dog population that are not in the wolf population. As the domestic dog genome contains the grey wolf genes and other alleles as well, that shows that the total information content in the domestic dog is greater than the total genetic information in the grey wolf, because the grey wolf genome is a subset of the domestic dog genome.