What is a common ancestor? If we have always been human and a spider has always been a spider then how can we have come from a common ancestor?
You're not listening to what I'm saying.
"Human" or "spider" isn't a switch that gets turned on in the genes. It's a human-invented distinction to describe a group.
A group of organisms which were similar to modern humans gave birth to many offspring, some of which were closer to modern humans, and those are the ones that tended to survive. Then those offspring had offspring that were closer still. And so on. After many, many, many generations, they crossed over a fuzzy man-made distinction that allowed us to describe them as more into the modern human category than not. Then they continued to evolve to become what they are today. And even today, we continue to evolve towards something else.
This isn't "X gave birth to Y", this is "over many generations group X slowly changed to look more like more modern group Y".
Were there millions of common ancestors or was there just one?
Both. There were lots of common ancestors to both modern humans and modern chimpanzees, for example. These were entire species that led to other species, not one single individual that led to a new species.
But if you're talking about common ancestors to all life, it might be one, but we don't really know.
You have to understand that there are "most recent common ancestors" between different species, and then there is the "common ancestors" to all life. The phrase can refer to either.
Is evolution saying one thing had all the genetic make up of all things?
Nope. Not at all.
Features that exist in one species could have evolved in that species, and not have existed at all in earlier species, though often there was some precursor it evolved from which had a different function.
If one thing had the genetic make up of all things, that would be evidence for creationism. But the evidence points to that not being the case at all. Evolution has demonstrated that it's remarkably good at evolving some new traits without that trait already being "built-in" somehow.
If that is so then a spider was not always a spider and a human was not always a human.
Well, it's not so. And, again, and I shouldn't have to say this, but a spider is, by definition, a spider. You keep getting hung up on this, and not being able to see that it's just a human categorization, which in reality has some very fuzzy edges.
We evolved all separately from one thing a common ancestor. Hence we evolved from something that we were not from the start.
You're using the word "we" wrong here. "We" are the end result of this process. Other species are what evolved from other species, right up until those other species actually became "us", but that boundary is fuzzy. There is no clear cut off between "us" and "not us" because this is such a gradual process.
And there is no way to test or reproduce that.
Sure there is. Run simple breeding experiments and then extrapolate from the evidence. Or look at the DNA for markers that would show that this is what is happening. Or look at the fossil record to see if it matches this pattern. Or look at the distribution of species and see if it matches what you'd expect if this were true.
And we do do these things, and all of them support the scientific theory of evolution.
And that really cool animation you gave is an assumption because there is no evidence that actually occurred.
I don't think you understand what "evidence" is. The fossils themselves, the order that they appeared, the physiological similarities, all of these things and more are the evidence that that actually occurred.
What exactly do you think evidence looks like? This isn't a rhetorical question, I'd really like to know your answer to this.
We don't have a fossil record of spiders being anything but spiders.
That's because, by definition, spiders are spiders. If something wasn't a spider, then it wouldn't be a spider, now would it? You really need to stop getting hung up on using this incorrect language to describe evolution, because it's hampering you from understanding what it really says.
Now, let me ask you a question, what is this?
Is that a spider? A scorpion? Something else?
And what about this?
Is that a tick? A crab? A spider? Something else?
How about this?
The fact is, all of those organisms have features of both the things they evolved from and the things they evolved into, so how would you categorize them?
I could go further back in their lineage, and as I did, they would look less and less like spiders, but they are still likely ancestors of the modern arthropods.
Once again similarities are not evidence of evolution unless you assume they are.
It's not merely "similarities", its similarities which are expected and predicted within the evolutionary model. This isn't merely an "assumption", it's the most likely conclusion from the evidence. Evidence which, were we not able to find any, would disprove that model.
Similarities are evidence if common design.
No, they're not. In order to be evidence for a model, there has to be a way to falsify the model. If the model cannot be falsified, such as the creationist model, then nothing can be evidence for it, because nothing could be evidence against it.
Evidence of evolution would be actually having something transforming into something else.
Things aren't "transforming" into other things in the evolutionary model, so you're using incorrect language again. Evolution doesn't happen at the individual level, it happens at the species level, usually over many, many generations.
That being said, the fossil, genetic, and geographical evidence of various species evolving into other species is in great abundance.
Like actual evidence of whatever it was slowly over millions of years transforming from something that didn't look like a spider into a spider.
We have that. I gave you some examples above.
All we have is fully formed fossils of millions of different things all existing at once.
You say "fully formed" as though evolution predicts there would be half-formed creatures or something. That's
not what evolution says.
The species is "fully formed" at every step of evolution. There are no non-functional "half-wings" or whatever it is you're alluding to there in the way evolution works.
Also, they most certainly weren't "existing all at once". We find species appearing and disappearing throughout the fossil record, most species never meeting the others from other time periods.
All the testing we can do is only to show similarities. All the testing we can do is to show how a particular thing like a virus or a bird or moth can adapt and change to survive and yet still remain a bird or a moth or a virus.
That's just completely wrong. We have
tons of evidence. You rejecting that evidence or being unaware of it doesn't mean it doesn't exist.
I think you just don't understand what the word "evidence" means in this context. Allow me to quote Wikipedia:
"
Scientific evidence is
evidence which serves to either support or counter a scientific theory or hypothesis. Such evidence is expected to be empirical evidence and interpretation in accordance with scientific method. Standards for scientific evidence vary according to the field of inquiry, but the strength of scientific evidence is generally based on the results of statistical analysis and the strength of scientific controls."
Thus, for example, finding fossils which appear in a sequence which supports the evolutionary model is, by definition, scientific evidence for that model.
In the light of that, can you at least admit that there is a lot of scientific evidence for the theory of evolution?
EDIT: Also, I'm going to repeat to you the same question you keep dodging:
What exactly would evidence of evolution look like to you? (And
please, make sure what you're asking for is something that evolution
actually predicts would occur.)
It's rather telling that you keep avoiding answering this question.