Ok, Zoe - back to you.
I have no qualms with difficulties in interpretation. Just the opposite, I make a pretty big deal out of it when discussing these issues more generally. I have said this a million times before: facts are objective; their interpretation is not. Of course, the fact that interpretation is subjective does not mean it is not true, nor does it mean that we cannot know it is true. But it is an extremely important distinction to make, for just because someone says "science says this" or "no, science says that" doesn't make it so. In large part, one's philosophy of science will have as much to do with what "science says" (in popular vernacular) as anything else.
So, we have the example we've been working with here. We have two separate
models (read: interpretation of a given set of data), both dealing with the divergence of Neandertals from modern homo sapiens. One model is based on the fossil record. The other model is based on nuclear DNA record (here, excluding the mtDNA model as it is in broad conformity with the fossil model). Neither model claims to be 100% accurate. Both come with the caveat in the first paragraph. I have no problem with that. But, I do have a problem in general:
Both can't be
true. One model places the divergence 200+K years before the other. So, we seem to have only four logical possibilities here to explain this:
1. One of the models is wrong while the other is right;
2. Both models are wrong;
3. At least one model has an excessive error rate;
4. The models are wrong in that they are not universal, but correct in that they could refer only to the particular populations from which the sample came.
Considering these (1) seems the most obvious, but of course, if (1) is true, (2) may just as well be true. Thus the entire problem with an inductive science, because if A is wrong, then how long before another study comes along and calls into question B? While we don't want to fall into absolute skepticism, the difficulties in interpretation you mention make our ability to differentiate between the two limited at best.
The third is, to me, simply unacceptable, and was my primary motivator for asking the question. If this is what people mean by "science," then my already low respect for it just went out the window. I can hardly believe an error rate of 50% is anything like acceptable, and so am forced to conclude that any rational scientist would take one of the other options.
Which leaves us with (4). I am not a scientist, so I can't comment if it is even scientifically possible (just talking about the logic here). But if that is the case, it calls into question our ability to EVER know when a universal divergence occurred, because, it would seem to me, every human being comes from a local population. There is no "universal man." So this idea also goes out the window.
Then, is (1) or (2) the correct response? I don't know, and unless someone here has a Ph.D. in molecular biology AND paleontology, I'd politely suggest that no one here does, either. The best any of us here can do is take what these scientists say on their personal authority. Fine. But, in admitting as much, you can surely see why I am absolutely unimpressed and not in any way inclined to make a personal judgment on the issue. As I, then, will not make a judgment on the issue, I will hardly use it in judging issues which I
am qualified to judge.
Concerning textbooks, that's an argument I'd rather not get into here. Suffice it to say here, I personally do not believe it is a matter of bad communication; I think it is outright indoctrination and purposeful misinformation. My question, which lends to my general incredulity, is if "they" are willing to do that to our children, why not to us as well? As I said, though, that's a separate issue worth it's own thread, so you can have any last words you want on that subject.
God bless, and thank you for the information you've supplied.