A prediction that Darwin wouldn't have thought of is that these non-functioning genes will be found in species For example, if a gene x for a function that is no longer needed for a particular organism, then if a mutation stops this gene working then all the ancestors of this creature will have this same mutation (known as a pseudogene).
If x is damaged by the insertion of a section of DNA (but where the damage does not affect the survivability of the organism)
then the chance of this exact same damage being done in another organism is extremely low. Therefore if we see this exact same damage in two organisms it is a safe assumption that these will be related.
If we examine the genomes of these two organisms we would expect to see many of these. Any one of them would be extremely unlikely, but finding many would increase the improbability exponentially.
Apes and guinea pigs can't make vitamin C, they need it as a suplement in their diet. All apes have a version of the gene that is damaged in a particular way, but with slight variations. Guinea pigs have the gene damaged in a different way.
From this it is easy to conclude that the apes are related and the guinea pigs are not.
If we then go on to examine the slight variations, there is a pattern within the apes. This pseudogene in chimpanzees and humans is very close, but orang utans have more variations.
Once again, if this was the only example, then it would be strong evidence, but the existence of many of these, and all showing the same detail makes it conclusive.
Where within creationism is the prediction about the same pseudo genes being found in chimps and humans, whilst similar ones found in orang utans whilst different ones found in guinea pigs?
The chance of one of these happening in two creatures by chance is negligiable. Finding many is as close to impossible as makes no odds unless the creator created chimps and humans with the pseudogenes in place. This is not a prediction of Creationism.
Creationists say that humans were created seperately, and are not related to chimps. This means the creator must have put exactly the same faulty genes into chimps and humans, plus all the other pseudogenes.
It is not necessary that the pseudogenes have to be in the form they are in creationism. In fact if humans had the guinea pig pseudogene it would not be a problem for creationists but would be a huge problem for evolutionists.
The point is that any combination of pseudogenes will fit creationism, but only one combination will fit evolution. The fact that the one combination we do have fits evolution is one piece of evidence for the theory.
This evidence is not enough on its own to show that the ToE is correct, but it is one part of a list of evidences.
