Corona688

Troll Hunter, where are you?

Quetzal

Randman: Although most of what I want to post has been covered elsewhere (by scombrid and Mr. D among others), I think I am dimly beginning to glimpse some of the problems here. With your indulgence, I’m going to make a radical departure from the normal course of this type of discussion, and take your suggestion: I’m going to take a step back. There is method to my madness – I think one of the fundamental problems here is you don’t have the same understanding of speciation that the evolutionists on this board have. Beyond your apparent fixation with Gould, I think we’re talking past one another. So I’m going to take the bulk of this post to try and give you some idea of what evolutionists mean when they talk about change in species. Afterwards, I’ll be able to put the gradualism – PE debate into something like an understandable context (I hope), and maybe even give you an idea why what evolutionists call “transitional fossils” doesn’t necessarily match what you seem to be expecting.

Evolution doesn’t proceed by sudden leaps – saltation – in major morphology. The basic reason is that the larger the effect of a given mutation, the more likely it will be deleterious – and kill the mutant. That’s not to say small mutations can’t have a deleterious effect on the organism, just that large ones would be almost invariably fatal. What normally happens is that a small mutation occurs in a population, splitting the species into two different varieties. Now if these two varieties lived close by one another, the odds are that they would interbreed, and the mutation would be suppressed or eliminated. Allele frequency tends to be pretty hard to budge once fixed in a population. However, what would happen if a portion of the population carrying the mutation were to become geographically isolated from the parent population? The mutation, if it provides a net survival advantage in the new area, will rapidly become fixed in the new population. In addition, both populations continue to change due to environmental conditions, or even chance (genetic recombination, additional mutations, etc leading to changes in allelic frequency in both populations). If the two populations are reunited eventually, and they don’t interbreed, then we can say they are in fact two distinct species. The longer they are apart, the more differences we would expect.

Here’s the catch: from observation of living ecosystems, we see that the heaviest competition occurs between very closely related species. In the above allopatric speciation case, the species that is best adapted to the current environment is likely to survive, while the other goes extinct. Guess what this would most look like in the fossil record? The “sudden” miraculous appearance of a new species.

Alternatively, the parent species may no longer be living in the region when members of the daughter species return. Climatic conditions, new predators, disease, or whatever may have either killed the parent species or forced it to move away. It disappears from the fossil record. The daughter species, which because of the vagaries of fossilization didn’t get into the record before (or hasn’t been found), is now miraculously discovered in the new area. The “sudden” appearance of a new species.

Neither of these changes actually occur overnight. When a paleontologist or biologist talks about “sudden”, they’re not talking about a year, or a few millenia. Even 100,000 years is barely an eyeblink registry in the geological record. In fact, my geologist friends tell me that it isn’t even always possible to give an absolute date to a strata within even 1 million years (depending on age, obviously). So “sudden”, in this context, could literally mean millions of years. Voila, your gap – fossils found at a given geological site will not exhibit gradual series of small morphological changes if the evolution happened somewhere else.

(Just a bit of evidence to show I’m not making this up: there are fossils of relatively modern hippos and lions in England dated to ~120,000 ya. Obviously, there are none living there now. Did hippos go extinct? No, their descendants moved south when the English weather turned too cold for them at the start of the last ice age series. If they don’t fossilize in Africa, a future paleontologist could logically (albeit erroneously) say they went extinct during the Pleistocene!)

Let’s take a look at evolutionary stasis. There are really two related issues here. In the first place, if I might be forgiven an anthropomorphism, natural selection tends to be “conservative” (if it ain’t broke, don’t fix it). Once a population or species becomes adapted to its environment, natural selection will tend to weed out any misfits. There will, of course, be variation, but it will tend to vary around a mean frequency. This “evolutionary stable strategy” is difficult to upset unless the environmental variables change. When an ESS experiences disequilibrium, the population either adapts (by NS favoring the expression of all those suppressed alleles), moves (habitat tracking), or goes extinct (crash). In the latter two cases, we’ll see an abrupt disappearance of a species from a particular geological site.

The other related issue is the fact that, in an environment that doesn’t change much over very loooong periods of time, an ESS – once achieved – will favor those populations best adapted to that environment. In places like the ocean, where conditions are pretty invariant, this apparent “stasis” can last millions of years – basically until something relatively drastic occurs to cause change. I think it is significant, in this context, to remember that Gould and Eldridge were studying marine organisms when they came up with their theory (snails and trilobites, respectively). Also, this aspect of PE theory IS generally accepted by evolutionary biologists – as a descriptive, not a mechanism, and not a very revolutionary observation at that. Once a stasis situation changes, radiation and adaptation occur “rapidly”, as natural selection operates on the remaining population – permitting radiation into new niches created by the change in environment, and favoring those traits that are more adapted. (One of the things we see is that often it’s the non-specialist organism that is favored! The exquisitely fit organism, near-perfectly adapted to the existing environment over eons, simply can’t change quickly enough to survive.)

I’ll try and get something out on fossils later, and try and relate what I’ve written to your specific post. I’ve given you a bit to chew on here.

MrDarwin

Well heck, here's your chance! I'm sure Patrick would be delighted for you to do exactly that on this discussion, where the best you've been able to do so far is post some URLs:

<a href="http://iidb.org/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=58&t=000370" target="_blank">Randman says we've ignored AiG's "best arguments"</a>

Daggah

Even if they WEREN'T out of context, they'd still represent an argument from authority on your part.

randman

Morpho, I am fully aware of the things you have posted, and I beleive that when Stanley says the extreme rarity of transitional fossils is the trade secret of paleontologists that he is doing so within the context of what you are talking about.
My point here is to parse the theoritical from the actual hard data. It may be that isololated groups of species separate and create new species. I don't even think the creationist has a problem with that. And it may be that this speciation is how it occurs, although I beleive evolutionists used to think population geneitcs would cause a whole population to change, but that is another thread, and I don't want to get off-base here.
However, the fact is we don't actually see this documented in the fossil record. We don't see the transitions, and any that we do see are limited to well within what a reasonable person would call variation within a kind.
Nevertheless, evolutionists refuse to admit this and state a bald-faced lie that the transitions are documented. They even do this while they debate the exact transition!
This, my friend, is really deceiving the public upon whom many evolutionist researchers depend upon for their grant money.
Why not admit the truth up-front without all this fuss, and simply state, you guys are right. We don't see the transitions, and this is why. You coauld even argue that we don't expect to see the transitions, and go on to educate the public and classrooms as to some real science, but what is relied on is propoganda methods. Evolutionists lay out a huge list of "transitional species" leaving the impression that the fossils of these particular species actually evolve when in fact they do not.
They are only transitional if you assume evolution occurred. They are called transitional based on similarites.
But the fact remains the transitions themselves are not shown.

randman

I can hardly see how a bunch of guys who want you to list your credentials can complain about an argument from authority, and pray tell, how else are we going to know the data if we don't ask authorities.
What I object to and ya'll hypocritically subscribe to is your false arguments from authority. To argue a conclusion from an authority without showing, nor stating the facts, is actually an argument from authority that is false. This is precisely what ya'll have done in quoting Gould's complaints and conclusions without explaining the data, and as I mentioned elsewhere, evolutionists frequently do this by stating that most scientists agree with them, etc,,..
So, in fact, you are actually just being a hypocrite and falsely accusing me in this area.
I qoute not Gould's interpretations as much, since I disagree with them, but his actual data. That is a different matter than arguing from authority, and it is this kind of lame argument by evolutionists that have caused nearly half of Americans to think evolution is a myth.
I mean it sure appears such by the way ya'll argue it.

Daggah

I don't remember anyone in that thread saying that, because they have credentials their argument is valid. Often creationists present out-of-context quotes (and sometimes even utter lies) as evidence against evolution, but this is an argument from authority. Evolution is to be weighed on the basis of its evidence, not on the basis of what some authorities think.

We know the data by asking them; we don't automatically accept it because it comes from them.

Really? Wow, I wouldn't have realized that. This is what you're doing.

BULLSHIT. We've quoted Gould to show you that he is not meaning what you claim he is. Stating the obvious (that Gould knows his arguments and papers better than you do) is not an argument from authority.

Most scientists who have objectively weighed the evidence DO agree with evolution. This only means that they agree with it; it in and of itself does not represent evidence FOR evolution. If we claimed it did, we WOULD be guilty of using the argument from authority. We are not doing so.

This, too, is utter tripe. You submit conveniently chopped-up and out-of-context quotes that are not supported by what Gould ACTUALLY THINKS.

Nearly half of all Americans (which, by the way, is you using an argument from popularity fallacy, now) are against evolution because of their a priori assumptions in favor of Biblical truth, randman. This is why less fundamentalist Christian nations tend to accept the obvious facts of common descent more often than America does.

Quetzal

Randman: You state that you are “fully aware” of what I posted. I’m not clear from your response, however, that you read the full post – or if you did, I’m not sure you understood it. It is very apparent you didn’t catch on to the implications.

You continue to assert in various threads that:

1. “Sudden” appearance of species in the fossil record is unexpected for evolutionary theory.

2. The fact that certain species manifest evolutionary stasis longer than others is somehow a falsification of evolutionary theory.

3. Gradual morphological change in a lineage is predicted by evolutionary theory, and since undocumented in the record, proves the theory false (which was actually addressed in my first post, as well – cf. squirrels).

All three of these points were addressed in my last post (and have also been addressed by others on other threads). The key question you failed to ask – which makes me wonder whether you actually read or understood the information I posted – is how we know these things occurred. The answer is: from observation of living ecosystems. Every single one of the points I raised was based on modern organisms and their interactions within modern ecosystems. Environmental adaptations, habitat tracking, interspecies competition, species-to-species transitions, mutation/variation, gradual morphological change, environmentally-induced species extinction, ESS, rapid speciation, and even the relative success of the “generalist” over the “specialist” in a changing environment are all readily observable. If we can see such processes occurring before our eyes, there is nothing in nature to preclude them from also having occurred in very much the same way in the past. Oddly enough, what paleontology, paleobotany, paleoecology, paleoclimatology, etc, have been able to piece together from the very fragmented fossil record, bears out this contention.

Obviously, given the limited time humans have been observing nature with anything resembling an analytical eye, we don’t expect to see the BIG transitions in living systems (between higher taxa, for example). Given the amount of time it takes even rapid-generation organisms to vary enough from the parent population to consider them new species, the amount of time for large-scale morphological change to become fixed is extremely long – much longer than we have been observing. The only place we see such changes is…[drum roll]…the fossil record! The problem with the record is, as I posted before, that we don’t have a nice generation-by-generation series of “begats”, to prove beyond even your hyperskepticism that branches of the “mangrove of life” are, in fact, related.

I know you’ve been given the A…T…B explanation numerous times, so I won’t repeat it here. If you consider this to mean that A begat T which in turn begat B, you’re barking up the wrong tree. Because of some anatomical similarities, we know A and B are distantly related. Because B shows up higher in the strata, we know that B is “younger” than A. Since T shares more traits with A and B than either share with each other, we state that T is transitional. This is, in reality, a convenient way of describing relationships – it has little or nothing to do with who begat whom in nature. This, I think, is where your confusion seems to arise. We can only detect gross morphological differences at such a great remove in time. In short, in the fossil record, we can only detect changes in major taxa. All the silly confusion over “lack of transitionals” stems from this one simple fact. Remember the squirrels…

I’ve got another little “trade secret” to share with you (a la Stanley), this one from modern ecology: there are a lot of living organisms with no direct fossil ancestors! (Shhh. Don’t tell the creationists. They’ll assume it’s evidence for separately created “kinds” rather than realizing that it’s an expected artifact of the gaps in the fossil record – as I’ve discussed.)

As to your continuing diatribes against the Vast Evilutionist Conspiracy (pat. pend.): I don’t know what miserable experience you had with biology as a student. I don’t really care, and to be honest your continuing insistence (without any evidence to back your assertion) is getting tiresome. Rather obvious, at least to me, is the fact that there are an awful lot of people on this board who didn’t have a problem with evolution (and as far as that goes, off the board), and didn’t have whatever revelatory experience you did. Guess what? You just might be wrong…

I probably won’t be able to post for a few days – I’m going to be on airplanes and in airports for the next couple of days. However, I don’t see a whole lot I can add to what I’ve already posted unless you can come up with some substantive rebuttal or question, anyway. I’ll try and check back in when I get a chance.

MrDarwin

Well, if by "authorities" you mean "biologists", when we ask them about evolution 99.99% (if not more) of them say it's as proven a fact as is anything in science. The primary area of disagreement is in modes of evolution--how it has taken place--not whether it has taken place.

So, pray tell, are all these "authorities" completely mistaken? Fools? Idiots? Bald-faced liars? Are you really saying that you understand evolutionary biology so much better than the people who have made evolutionary biology their life's work that you can say they are all full of hooey? Why should we listen to you, and not to them?

[ March 09, 2002: Message edited by: MrDarwin ]</p>

randman

Morpho, what I am looking for is the kind of acknowledgement found in the following quote.

“Few paleontologists have, I think, ever supposed that fossils, by themselves, provide grounds for the conclusion that evolution has occurred. The fossil record doesn’t even provide any evidence in support of Darwinian theory except in the weak sense that the fossil record is compatible with it, just as it is compatible with other evolutionary theories, and revolutionary theories, and special creationist theories, and even ahistorical theories.” [David B. Kitts (evolutionist), "Search for the Holy Transformation," Paleobiology, Vol. 5 (Summer 1979), pp. 353-354.]

I understand what you are saying, and I don't have a problem with evolutionists stating we beleive evolution happened due to the things you have stated. I do have a problem with them mistating the data in the fossil record.
The fossil record is actually fully consistent with special creation models where micro-evolutionary changes, but not macro occur after a species is created by God.
This is a fact, but evolutionists lie and state the fossil record proves evolution and disproves creationist and ID models.
I have no problem with using the study of current evo-systems to argue for a way to "intepret" the fossil record, but to flat out deny that the fossil record is consistent with creationism is just wrong.
This is why I state evolutionists lie and use propoganda. Take the idea of transitional fossils. If by transitional, it is meant that the transitions are shown, then this is wrong. There are no transitional fossils according to this definition, which would be the layman's way of reading it.
There are only transitional fossils based on a circular type of reasoning.