MrDarwin

As a little experiment I'm going to do what I haven't seen any creationists do yet here: provide a putatively testable hypothesis for a non-evolutionary history of life. First we start with the observations, meaning the pattern we have to explain:

(a) the fossil record shows a long and continuous history of life on this planet
(b) the fossil record shows that new organisms have appeared during that history, at different times
(c) the fossil record shows that younger fossils tend to be more like organisms alive today, and older fossils less.

Here are some hypotheses to explain these observations:

(1) Life has changed and diversified from common ancestors without any outside influence

(2) Life has changed and diversified from common ancestors, due to the influence of an external agent

(3) New life forms have appeared de novo throughout time

There are other possibilities, but I think these are the three main ones. For each, here are proposed mechanisms of change:

(1) random mutation and natural selection

(2) genetic engineering or some other kind of conscious "tinkering"

(3) Divine intervention, magic, etc.

And here are my questions:

How would we go about testing or potentially falsifying these different explanations?

What differential results might persuade us that one of them is a better explanation than the other two, or that two of the three or even all three may have occurred (as they are not mutually exclusive)?

Please guys, keep this serious and rational, for 24 hours at least.

randman

I am not going to try and give you a full-orbed answer, and I would appreciate you and anyone else not assuming that I am obligated to, unless your goal is to merely keep critics away from the little party here.
I do think one idea touches on some of these ideas, and that is irreducible complexity, say of the knee for instance.
If any instances can be shown that a very gradual and incremental process is unfeasible for evolving any aspect of the evolutionary tree such as evolving the knee, then that is evidence that disproves the purely natural means that we are aware of, and is evidence for design.
Now, you may state there is no way to test a presumably higher being, etc,..but we can examine the evidence in light of the idea that something has occurred and see if it fits. We can examine the results and posit 2 conclusions if irreducible complexity is true. The first is there are natural, or other, means of things occuring that we are unaware of. Secondly, we can posit that some type of intelligent will is involved.
I would also point out there really is no way to actually test for much of evolution having occurred since we haven't yet been around long enough to see natural processes creating macro-evolution, as I understand that term.

Peez

My, we are a little defensive. I would agree that if it could be shown that a particular phenotype could not have evolved by natural selection, that the process of evolution by natural selection would be falsified. Note that this would not falsify common descent, only the mechanism. I would suggest, however, that it would be very difficult to show that a given phenotype could not possibly have evolved by natural selection. Certainly, however, so-called "irreducible complexity" can evolve by natural selection, so it does not qualify as evidence against natural selection. To do this, we need to identify what potential observations would be incompatible with the existence of a "higher being." I can think of none. As I mentioned, irreducible complexity is not evidence against evolution by natural selection, something that could not evolve by natural selection is. But let us assume that that is what you meant for the time being. Sorry, you lost me here. Wouldn't "natural, or other, means" include everything (natural selection, one or more gods, other intelligent agencies, random chance, etc.)? O.K., let's say either it was a natural process without intelligent interference, or one or more intelligences were involved. It is interesting that you first propose a way to test evolution, then claim that there is "really no way to actually test for much of evolution having occured [sic]." Of course the evolutionary history of life can be tested. If a fossil mammal were found in Precambrian rock, evolution would fail such a test. If a snake with codons entirely unlike any other were found, evolution would fail such a test. If a beetle with a vertebrate skeleton were found, evolution would fail such a test. There are literally millions of ways that evolution could be falsified, and there have been millions of tests, and evolution has passed each and every one.

Peez

MrDarwin

Here's the problem: how does one show this is "unfeasible"? I'm just asking for suggestions--how does one go about testing this, to prove that something cannot happen?

For example, how do we test the proposition that bird wings did not evolve from reptilian forelimbs? How would we expect the fossil record to be any different, if one or the other proposition is true?

lpetrich

I think that we could divide the first possibility into to:

Darwinism: Random mutation and natural selection (a nonrandom effect, of course).

Other natural laws that can produce evolution: inheritance of acquired characteristics, direct induction from the environment, orthogenesis (evolution by internal forces), etc. Some have claimed that species go extinct because a whole species will suffer from a kind of old age if it lasts long enough.

Inheritance of acquired characteristics is most commonly associated with Lamarck, who had believed that the most important cause of evolution was some orthogenetic mechanism that produces continual progress.

Direct induction from the environment would explain camouflage and the like.

As to orthogenesis, one will have to be careful; much molecular evolution is essentially genetic drift, which produces a statistical sort of orthogenesis. This mechanism, however, is completely consistent with Darwinism (random drift between equally-functional alternatives); I have in mind some orthogenetic mechanism other than that.

[ March 22, 2002: Message edited by: lpetrich ]</p>

randman

Well, this is a little off-subject, but I wonder if evolutionists do much research on instinct. Take for example how baby turtles know to head for the ocean when they are born. How do they know that?

Can the body itself contain behaviour directions within it? Thirst for example is something our body tells us more than our mind. Our mind interprets the message of course. Is it possible that animals have built within them information that is passed down in the form of instinct, and if you buy evolution, does this mean learned behaviour can be passed down?

Kevin Dorner

It's not that learned behaviour is passed down, but instead, in your example: in the population of turtles there would have originally been babies that went to the sea, and ones that didn't but instead wandered randomly or went in the wrong direction or just sat there... anything but going to the sea. The ones that didn't seek the sea dehydrated and died and were not able to pass along their genes for their behaviour. The sea-seekers lived, reproduced, and passed along the genes for sea-seeking, until the entire population had these genes. This is natural selection at its simplest and most basic.

[ March 22, 2002: Message edited by: Kevin Dorner ]</p>

Coragyps

I don't know about sea turtles, but there's always Google. Many other animals have "sensors" to facilitate behaviors that you have to go looking for to ferret out how they work. Naked mole rats (not moles or rats, but a naked African mammal) have magnetic sensors in their brains which act as a compass - in new surroundings, they will orient themselves in a natural or applied magnetic field. See Unfortunately, the capatilists at Science want to eat, too, and so charge for access to papers - this was an interesting one.

I would think a baby turtle would have several clues to work from - sound of waves breaking, differential lighting of moonlight over land vs. sea, maybe a compass (?). Certainly more than a mole rat in a dark burrow. And Kevin just gave you the mechanism for how whatever it is gets passed down.
I'll go Google on turtles while you guys duke it out here.

Edit: is it just me, or does anyone else think of Elizabeth Taylor overacting in Suddenly, Last Summer every time they hear about baby sea turtles? Blewwwweccch.

[ March 22, 2002: Message edited by: Coragyps ]</p>

Coragyps

That was quick: This is after they get to the water - but the right idea seems to be there.

Edit this one, too: Loggerhead sea turtle hatchlings, at least, use light to get to the water, and can be fooled by artificial lighting inland. That sounds like a pretty simple hardwired, genetic behavior: if you don't head toward the brightest sky as a baby, you won't grow up to make babies.

[ March 22, 2002: Message edited by: Coragyps ]</p>

MrDarwin

Let's step back a little from any ideas about "superior beings". Let's say that we're looking in a remote corner of Siberia and find some very, very odd animals. Let's say that we have suspicions that they were created by genetic tinkering by the Soviets. Would we be able to distinguish whether this is the case, or whether they had evolved, entirely naturally, from some pre-existing animal? How would we test the two competing hypotheses, and what kind of evidence would sway us one way or the other?


And yet all evolutionary biologists believe that there are indeed ways to test whether evolution has occurred.

What I'm getting at is whether the kinds of evidence would be different. In the fossil record, would we expect to find one thing, or would we expect to find an entirely different thing, if naturalistic evolution or theistic evolution or intelligent design or purely supernatural creationism were true? Should we expect the fossil record to provide us with any kind of evidence for one or the other hypothesis being true, and if so, what evidence?