We can SEE this genetic potential in all sorts of plant and animal breeding. This can be seen today.
So you observe variation in dog breeds, for example. Either the variation results from recombination of alleles through sexual reproduction and mutation, and the breeders choose the puppies that are the most like the dogs they want, and they use those to breed the next generation, or else all of the breeds of dogs are already hidden in every dog, or some earlier dog, and they do...er what?
If that second one was true, and you knew how it worked, you could have saved dog breeders a great deal of work over the past 15,000 years. What would you tell a dog breeder who thinks he has been choosing from random variations all this time? Do you know a better way to expose the hidden variations? Do you believe that there is a limited number of dog breeds possible because they all exist already, but are somehow hidden? Is this knowledge you have actually useful for anything?
One thing that cannot be seen or tested is a "single common ancestor" of all living things.
Can I ask how you know this can't be tested?
Evolutionists just need to stop pushing mutations as improvement. Mutations are damage; plain and simple.
Off the top of your head, can you give an example of a damaging mutation?
Evolutionists often use man-made, intentional changes (intelligent design) as if this somehow proves that random errors can have total creative power to turn chemicals into men (and women).
The chicken teeth thing is not about everything you list, it is specifically about the presence of suppressed genes that can be reactivated to make a feature that birds don't normally have.
This is not an example of Intelligent Design, because that is a claim about irreducible complexity, which is very specifically to do with adaptive features not having precursors, a claim that has been proved wrong for every example I've heard of.
In another thread, we established that there is no scientific theory of chemicals becoming a living cell, not because it's impossible in principles of biochemistry, but because of a lack of evidence from the specific event.
You appear to be criticising the aspect of this which requires intelligent intervention by scientists. That's very much like the intelligent intervention that would seem to be needed in the creationist model of variation within kinds. How are preloaded genes turned off and on?
The "why" of the cause of the change is not known and is irrelevant to the fact that the information is already there in the genes.
You will appreciate that without an answer to the question of how, the idea that a 'kind' already contains it's variation 'in the genes' loses out to evolution by natural selection of variation caused by mutation. That is a complete explanation. It is contradicted by no evidence. And there seems to be no room in the bacterial genome for extra, unused information kept in case the environment changes.
I have another related question for you: if the purpose of the stored variation within a kind is to help its survival in a changing environment and it was put there by an all-knowing intelligence, why then have over 99.9% of all species that ever lived gone extinct?
Stuart