Re: Creationists
I don’t know how anyone could answer your question to your satisfaction. i suspect you already have your answer and are only stringing this along to elicit you “ahaaa” moment.
None the less, i can play along. Variability becomes speciation when enough changes have occurred in a species genome to constitute a new species. One that is incapable of procreating, or producing a viable genetic line, with the species that followed it or other species that descend from a similar ancestor. There is an inevitability to this which you ignore given your understanding of genetics.
Mutation chain is seen in the fossil evidence. Mutation chain is seen in genetic markers which indicate when a species diverged from its ancestor or its level of relatedness to another species.
Lets get this out of our heads that there is any certainty to anything. All things in existence can be of doubt. You may not even exist as an individual for all I know, in fact, you could be a clever computer program dishing out rehashed quotes from creationist websites. However, given what I know, everything points to you being an actual person, so rest assured.
Science is not Philosophy however, and so scientists don’t have the luxury of pondering the meaning of reality and what is or isn’t real. Science takes the evidence that is given and draws conclusions from that evidence. in the case of evolution, there is a great deal of evidence to support it. The minuscule chance that similarity is a fluke, and god created all things as they are, and the evidence is misinterpreted, is so unlikely that it negates itself.
In science to, theories are often understood to be true on paper well before the are established to be fact through direct visual evidence, simply because the evidence for their support is so overwhelming. Speciation may well be visualized to be true in the future, but it does take a vey long time. Hence, we wil require a time machine of sorts, and then perhaps.
However, what we do have is basic logic, something you are ignoring. We understand that changes to an animals genotype can produce changes to its phenotype. We know that these changes occur over an average time scale, we know how these changes occur. We know that for two species to diverge requires changes in their genome. So logic dictates that speciation is a logical and inevitable consequence.
Why do you ignore simple logic here?
There is of course a small chance that God created all things as they are and similarity is then only the result of god reproducing what works. But science cannot rely on religion. Secondly, even if we do argue this from a religious perspective, creature variation could have come through evolution as a mechanism devised by God himself, or they were made magically and just appear as is. Even then, being logical creatures, knowing what we know, we have to conclude that the most logical and most likely conclusion has to be true. Evolution, and speciation in our case, seems far more logical and reasonable then things appearing as they are. Or would you attest to seeing things magically appear on their own. Did it rain cats ad dogs in England recently? How did I miss that one?
Joking aside, I doubt you have ever seen a new species just emerge magically from nothing. But you have seen animal variability produced right before your eyes. So which is more likely, Animals appearing out of nothing, or animals evolving, gaining variability and then becoming new species?