Science and Religion

[mmaestro]

"One cannot ask whether a theory reflects reality, just whether it agrees with observations."
-Professor Stephen Hawking

That was from an interview with Professor Hawking broadcast by the BBC on Thursday (hear the whole thing as an mp3 download here, it's fascinating). He was talking about the prospect of other dimensions, not really relevant here

Comments

[gunslnger]

Evolution, on the other hand, can be tested multiple ways, both through the development of cells and fast breeding species in the lab, and real world observations of ecosystems and the fossil record.

The first two examples are testing microevolution or adaptation and the second two are not testing anything, just making observations. So no, Evolution (or properly, the Theory of Evolution) cannot be tested, in the same way that the Theory of Creation cannot be tested.

[prufock]

The first two examples are testing microevolution or adaptation and the second two are not testing anything, just making observations. So no, Evolution (or properly, the Theory of Evolution) cannot be tested, in the same way that the Theory of Creation cannot be tested.

Many of these tests have shown genetic change in populations of species, and change enough to consider the descendant population a separate species. What percentage of genetic change would you require for something to be considered "macro" rather than "micro"? Since speciation has been observed, is a change in species not enough? Would you demand a change in genus, family, order, class, phylum, kingdom? What degree of change would cross your "macro"-threshold?

[gunslnger]

Since "species" is an [essentially] arbitrary term and "speciation" is not consistently defined, no it's not enough evidence for macro-evolution. Change in multiple features of a creature, or significant change in a single feature (over time) would be required to show that macro-evolution is a possibility.

[prufock]

It isn't that arbitrary, though you're right that it isn't consistent. The most common definition that I've seen in evolution experiments is interbreeding potential.

Change in multiple features of a creature, or significant change in a single feature (over time) would be required to show that macro-evolution is a possibility.
Change in multiple features has been observed. "Significant" change in a single feature is still undefined. What would you consider significant, and why? Like I said, what percentage of genetic change would be acceptable?

[gunslnger]

Change in multiple features has been observed.

Example?

What would you consider significant, and why?

It's difficult for me to express as I'm not a biologist, but the point is that the feature(s) of the animal needs to change more than just cosmetically. For example, can you describe what is really different between a horse and a donkey? They can't interbreed but they can produce offspring (a mule) when manipulated by humans. We have them classified as different species, but what are the differences?

[prufock]

How about change in both coloration and mating habits in cichlid fish? It wasn't experimental, though.

Horses and donkeys can produce mules or hinnies, but these offspring are almost always infertile. The offspring should be fertile for the parents to be considered the same species. I think ligers/tigons have the same infertility problem. Mules/hinnies and ligers/tigons are hybrids, not species of themselves.

It's difficult for me to express as I'm not a biologist, but the point is that the feature(s) of the animal needs to change more than just cosmetically.You mean genetically? I'm not a biologist, either, but it seems kind of unreasonable for someone who admittedly isn't well versed in the field to criticize the conclusions of agreed experts

[gunslnger]

My belief is that no amount of change short of a fly becoming an elephant in one generation would be enough to convince many of them, if that.

It's not that extreme, but it needs to be more than than just changing color or a different ear length. For example, look at all the varieties of dog. They are all still dogs. All of those variations are cosmetic, none of them change defining features.

[prufock]

That's probably why most experiments use the interbreeding criteria. Morphology IS pretty subjective. Regardless of how different species of dogs look, most of them CAN interbreed, though, an produce viable, fertile offspring. Morphology is subjective, but interbreeding populations are not - either they can or they can't.

[gunslnger]

It's better, but still not sufficient by itself.

And that's just the first hurdle. Beyond that, you have the logical leap to say that more complex features can change or be created over a longer period of time.

[prufock]

That's fine, and it's a reasonable criticism, but again, I've never seen that criticism followed by an explanation of what would be sufficient.

Can you explain what you mean by "more complex features"?

[gunslnger]

It's not necessary for the critical analysis to provide a solution. Showing where the theory is invalid (or at least lacking) is all that's needed. The problem is that theory proponents are so dogmatic about it that it's impossible for them to see the problems with it and fix it and asking the criticizers to fix it for them is just part of ignoring the problem.

A simple feature is something like coloration or ear size or leg length whereas a complex feature would be like eye structure or a new organ (or a missing organ).

[prufock]

I disagree. For any critical analysis to be considered worthwhile, there has to be a standard for comparison. If a critic says "That's not enough change to be considered speciation/evidence for evolution," it means that there is some standard that would be considered "enough." If they can't provide that standard, than the argument "That isn't enough change" can be used regardless of the amount of change taking place. If the critic can't supply, suggest, or even give an estimate of the standard, the criticism isn't convincing. It isn't about asking the critics to "fix the problem," it's just asking for criticism to be constructive.

I understand what you mean, but what makes a feature "complex" rather than "simple"?

[gunslnger]

If the critic can't supply, suggest, or even give an estimate of the standard, the criticism isn't convincing.

Well, I did, you just want it to be more exact than what's being criticised, even though I said I'm not in that field. I don't have the knowledge to make an alternate suggestion, although I do have enough to know that what's proposed currently isn't good enough.

I understand what you mean, but what makes a feature "complex" rather than "simple"?

I don't know how else to put it, other than it's obvious. I'm sure you can ask a biologist what are simple features and what are complex ones.

[sparkofcreation]

I'm sure you can ask a biologist what are simple features and what are complex ones.

Yes, in fact, they can. Biologists believe that ALL THE FEATURES MENTIONED ABOVE ARE COMPLEX.

So are you now saying that because all the things mentioned above are complex, you believe that there is demonstrative evidence of evolution and you accept the theory?

[gunslnger]

If a biologist were to say to me that ear size or shape was a complex feature, I'd call them an idiot and tell them to go back to school.

[sparkofcreation]

So first you say you don't have to define what is complex because a biologist should be able to define it. Then you say that even if a biologist did define it, you wouldn't believe them.

Ear size and shape is hugely complex; it dictates what frequencies can be heard, at what volume, and at what distance and relative position from the hearer. That's why dogs, humans, and bats all hear very differently.