Though the term is often used in an informal sense, there really isn't any such thing as scientific proof. Everything in science is tentative. All that can be done is increase the level of confidence that something is likely true. At some point a consensus develops around a set of ideas and explanations and a theory is born, one that is still tentative and remains open to change in light of new evidence or insights.
Scientific certainty is an erroneous claim you consistently make. Perhaps you should join a thread where we can discuss tentativity and why it's present in all science.
Until you can prove something through repeated demonstration you have an argument that is indeterminate - the yes/no urgency isn't there.
In science there is never any "yes/no". It would be better to think of accepted science as "very probably yes but always keep in the back of your mind that it may be wrong."
Look at the Standard Model in particle physics, one of the most successful theories of all time, yet a huge scientific contingent is convinced that it is very likely wrong in some ways or at a minimum incomplete. They have good reasons for thinking this, things like the lack of anti-matter and the presence of dark matter.
Evolutionary Theory is mired in this indeterminate stage.
To the extent this is true of evolutionary theory it is true of all scientific theory. You appear to be aghast at what science really is.
Discussing the evidence at a DNA level is pointless because 99% of the population that is aware of evolution is thinking at the macroevolution level: How did land creatures turn into whales, how did apelike creatures evolve into humans, etc. These are the big questions of evolution.
This "big question" has already been answered: descent with modification combined with natural selection.
If you're looking for the details of which mutations occurred when and spread through a population in response to which selection pressures, we do not know. But though we also don't know the specifics of how the planets of our solar system formed and took their current orbits we are nonetheless highly certain it happened through the laws of physics. In the same way, we are just as highly certain that the species of our planet took their current form through a process of descent with modification combined with natural selection.
What you're doing on the topic of evolution would be identical to saying to an astronomer, "You don't know how Pluto achieved its orbit, and that throws all your theories of astrophysics into question." Given that we've put men on the moon that would be pretty ridiculous, right? In light of this, do you think telling them, "You could be wrong," would be viewed as a serious argument? Or try, "The moon landings were faked."
This is similar to saying to evolutionary biologists, "You don't know which whales mated with which other whales with which mutations to produce which changes throws all your theories about evolution into question." Given that we can analyze DNA and RNA down to the nucleotide level, manipulate DNA at the nucleotide level using CRISPR, produce vaccines based on virus RNA, breed and/or genetically engineer crops and livestock, and analyze DNA to produce nested phylogenetic trees, that would be just as ridiculous, right? Or you could try, "It's all just a conspiracy, none of it is true."
Consider these questions:
1. What was/were the initial lifeform(s), i.e., what organism(s) are at the root of the evolutionary tree?
That isn't known, but there is great confidence that it was a single-celled organism.
2. How did the eyeball evolve? How did all of the eyeball sub-components develop concurrently through random mutation to eventually create such a profoundly useful feature? Without these sub-components working in tandem the eyeball would be entirely useless and would be naturally de-selected.
Specifically how, like which mutations when? We don't know.
But generally how? A mutation might be measured along a continuum from highly deleterious to neutral to highly beneficial. The more beneficial a mutation the more likely it would be to spread through a population and become fixed. Most mutations are SNP's (single nucleotide polymorphism, which is replacement of a single nucleotide with another) and cause only minute changes or no apparent changes at all.
There's a great deal of variation in vision. You undoubtedly know people who even though their eyes can focus perfectly they can not make out as much detail as you. Or maybe that person is you. In any case, this is due to normal variation within the human population of the density of cones and rods on the retina. The greater the density the greater the visual acuity and the lower that second number. 20/20 is considered normal, 20/18 very good, 20/15 incredible, and 20/10 incredibly rare and also incredibly beneficial to athletes in certain sports. Ted Williams and Barry Bonds had 20/10 vision. There are other aspects of vision that can be beneficial, such as stereoacuity and contrast sensitivity.
These variable traits of vision are due to evolutionary processes and can be selected for in a given population. Vision is more important to certain ways of life, and it is common to find that the average visual acuity is much higher in certain primitive tribes who still have a hunter/gatherer lifestyle.
3. In the cardiovascular system which developed first - The organs that required oxygen, the blood that carried the oxygen, the lungs that oxygenated the blood, or the heart that pumped the blood?
Same general type of answer.
4. Any number of unique features, like the chameleon's tongue, whose development through gradual mutation defies comprehension?
Same general type of answer.
I realize you've probably heard these all before.
And we realize you've asked all these before and have heard the same answers before, and we're wondering why some creationists do this, going from board to board getting blown up by the same points over and over again.
I suspect there are no definitive answers,...
Unlike religion, it is considered bad form within science to provide answers in the absence of sufficient evidence.
...and I suspect the answers that do exist are riddled with "might have", "could have", "potentially", etc.
Questions can always be asked for which there is insufficient evidence for an answer. That such questions exist doesn't invalidate what we do know.
Within these indefinite answers is where the great evolutionary leap of faith occurs.
If you are aware of any evidence that some scientific process other than evolution produced the diversity of life we see today, please tell us what it is. It wouldn't be correct to say that it is a mere assumption that, just like today, there has been selection of imperfectly reproduced life since the beginning of life, because all the evidence we have supports this. This is the same as some other sciences, such as astronomy and cosmology that believe the laws of physics in the past were the same as today, and all the evidence they have supports this. Or like geology that assumes that the same processes acting on our planet today, like sedimentation and erosion, uplift and subsidence, were also operating in the past.
Or as James Hutton said, "The present is the key to the past." However things happen today, that's how they also happened in all the days that went before.
--Percy
Edited by Percy, : Grammar.
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