Common Ancestry?

[Josh]

Originally posted 6/7/06:

“Evolution in the sense of common ancestry might be true, but evolution in the neo-Darwinian sense—an unguided, unplanned process of random variation and natural selection—is not.”

Christoph Cardinal Schönborn, the archbishop of Vienna

I found this quote from an article in Touchstone (link below) to be interesting. I must say, there are some (what I consider to be) powerful arguments for the common ancestry of living things while at the same time powerful arguments against naturalistic evolution.

Some explain the evidence for common ancestry as simply evidence that God doesn't like to wholly reinvent the wheel. I have to say, after sifting through the evidence lately, I might be leaning toward more connectedness between species than previously thought (aka, miraculous interventionary changes in species leading to new species).

I don't think this violates the "reproduce after their kinds" principle (if one could even call it a principle, really) in Genesis 1. I think the idea would be that animals and plants don't change into new species *on their own*. God may have miraculously altered some species to create new ones, working with existing material so to speak. The reference to things being created from the "earth" or "dust" would be seen as simply referring to all living things being made up of simple elements all around us (carbon first and foremost). These new species would then continue to "reproduce after their kind", or in other words, be stuck within their the perameters of their species unless God deliberately changed them.

Part of me thinks, what kind of a fool am I to post things like this on the web? The other part says I'm just exempflifying our values. I'm pretty tired of the evangelical tendency to cater to constituencies (or to fear them) being more important than honesty in regard to where one is at on this subject intellectually.

...If that last sentence didnt' make sense, I completely understand!

www.touchstonemag.com/archives/article.php?id=19-05-028-f

[hume]

Originally posted 7/3/06:

TCA

If anything, it seems to me that "macro-evolution" is more solidly established than "micro-evolution." By macro-evolution here I mean what's often called "the theory of common ancestry" (TCA) -- the notion that all life is literally related. This is distinct from any particular hypothesis (e.g., natural selection) about how this situation came about.

So it's interesting to me that critics of evolution so often proceed by accepting that natural selection does occur, then claiming that no one has shown that it can accomplish enough change to constitute speciation. Thus, it is argued, the theory of common ancestry is in bad shape -- look at its proponents desperately casting about for some mechanism, any machina without a deus in it, to show how apes could turn into men.

But this is basically backwards. The central insight of evolution *is* TCA. There certainly is argument among its proponents over the mechanisms behind it (tho I do think news of the death of natural selection has been greatly exaggerated in some quarters). Still, even if anti-evolutionists managed to totally demolish natural selection, they would have done nothing to deal with the abundant evidence in support of TCA.

I notice this may be emerging as a common point in our discussion here: you seem sympathetic to a kind of Theistic TCA involving close direct divine guidance of the process, based on the belief that merely physical mechanisms are insufficient to the purpose. I'm not miles away from that point of view either ...

[Josh]

Originally posted 6/28/06:

Most creationists start by denying common ancestry, favoring some kind of creation of each species ex nihilo (presumably) because they think that's what the Genesis text mandates. That's debatable, as I argued briefly in the above post (common ancestry).

"Still, even if anti-evolutionists managed to totally demolish natural selection, they would have done nothing to deal with the abundant evidence in support of TCA."

All their position can say about the evidence for common ancestry is that the Creator is reusing good designs when he makes new species from scratch, thus animals and plants have similarity not through physical relatedness, but through conceptual relatedness.

I'm just not sure I can buy that, tho.

So, I presume, our main disagreement lies in whether evolution can (or will) be shown to occur completely naturally or with some supernatural aid. Or are you possibly conceding some supernatural elements at this point? You at least seemed much more open to this in regard to the origin of life. If I can get an inch, I'll take another... heheh. Is any concession theoritical, or do you think at any point supernatural causes are to be preferred over natural? Under which circumstances might you?

[hume]

Originally posted 7/5/06:

"Most creationists start by denying common ancestry"

Granted that's their basic position. I was referring to a particular method of argument I've encountered more than once: begin by "refuting" speciation by natural selection, then present this as a devastating blow to "evolution" (by which is clearly meant, common ancestry). It's a semantic trick (or a sincere confusion), taking advantage of the loose usage of the term "evolution" to refer variously to TCA, natural selection, and "TCA via natural selection" -- which are really 3 distinct logical constructions. If you sort of muddle them up together, then you make your job alot easier (just dismiss one, then act as if the other has been sent packing with it).


"are you possibly conceding some supernatural elements at this point?"

It will never be demonstrated that supernatural causes could not have had any role in life's history: there's just no way to exclude that possibility. (If nothing else, one could always say, "God intervened to cause X, and he also made it look as if there were sufficient natural causes for X, due to some inscrutable reason of his own." But that sort of thing shouldn't be needed anyway, because many insufficiencies in our knowledge of the past are probably permanent, given how much of pre-history passes without leaving a trace of itself.) In other words, not to concede at least the possibility of supernatural elements is mere dogmatism.


"do you think at any point supernatural causes are to be preferred over natural?"

This, of course, is going further than merely admitting the possibility ... and here you're reaching the far limits of my (pretty slight) knowledge of the subject. The suggested natural mechanisms for evolution are all interesting, all intellectually compelling; but I'm totally unqualified to weigh their scientific value, or to compare that against "supernatural" alternatives (how would one compare such things anyway?). And, on the other hand, it seems foolish to glibly place boundaries on how God might choose to interact with his creation (I fear I've failed to follow this advice already on many occasions ...)

It's also relevant that evolutionary theory is a work-in-progress: the commonly accepted mechanisms are still under investigation, the details are still being worked out -- and of course, we can't guess what other possibilities might be suggested in the future. Given this, it may be premature to declare a final opinion on these matters. (Science can often be "unsatisfying" for those who are seeking finality. It's probably not the right place to look for that.)

[Josh]

Originally posted 7/11/06:

Interestingly, Intelligent Design theorists are open to common ancestry after all:

"Intelligent Design does nto require organisms to emerge suddenly or be specially created from scratch by the intervention of a designing intelligence. To be sure, intelligent design is compatible with the creationist idea of organisms being suddenly created from scratch. But it is also perfectly compatible with the evolutionist idea of new organisms arising from old by a gradual accrual of change. What separates intelligent design from naturalistic evolution is not whether organisms evolved or the extent to which they evolved but what was responsible for their evolution."

William Dembski, The Design Revolution

Furthermore, here is what Dembski says about the whole notion of "interventionism", or as we might say, the notion that supernatural creation (or evolution) involves God "tinkering".

I'm curious whether this line of thinking makes sense to you, Hume.

"For a designing intelligence to make a discernable difference in the emergence of some organism, however, seems to require that an intelligence intervened at specific times and places to bring about that organism and, thus again, seems to require some form of special creation. This in turn raises the question: how often and at what places did a designing intelligence intervene in the course of natural history to produce those biological structures that are beyond the power of material mechanisms? One of the criticisms of intelligent design is that it draws an unreasonable distinction between material mechanisms and designing intelligences, claiming that material mechanisms are fine most of the time but then on rare (or perhaps not so rare) occasions a designing intelligence is required to get over some hump that material mechanisms can't quite manage.

This criticism is misconceived. The proper question is not how often or at what places a designing influence first become evident. To understand the difference, imagine a computer program that outputs alphanumeric characters on a computer screen. The program runs for a long time and throughout that time outputs what look like random characters. Then, abruptly the output changes and the program outputs sublime poetry. Now, at what point did a designing intelligence intervene in the output of the program? Clearly, this question misses the mark because the program is deterministic and simply outputs whatever the program dictates.

There was no intervention at all that changed the output of the program from random gibberish to subliem poetry. And yet, the point at which the program starts to output sublime poetry is the point at which we realize that the output is designed and not random. Morever, it is at that point that we realize that the program itself is designed. But when, where, and how was design introduced into the program? Although these are interesting questions, they are ultimately irrelevant to the more fundamental question: was there design in the program and its outcome in the first place? Similarly, in biology there will be clear times and locations where we can say that design first became evident. But the precise activity of a designing intelligence at those points will require further investigation and may not be answerable. As the computer analogy just given indicates, the place and time at which design first becomes evident need have no connection with the place and time at which design was actually introduced."

William Dembski, the Design Revolution pp. 178-179

[Josh]

Originally posted by HUME on 7/11/06 (even though it says Josh):

The debate between theistic evolutionist and IDers (if there is one), would seem to revolve around the question, not of design per se, but of when one should pause to recognize design. IDers find many specific evidences of the creator's hand in nature, while TEists are more inclined to contemplate the whole as a single grand achievement.

Both camps would agree that if one steps back and views the whole story of life on earth (as much of it as we know so far), the proper response is awe; and surely the whole work is so grand in sweep yet so deep in detail that one can hardly help taking it as evidence of an incredible intelligence. Even atheists are tempted towards some kind of pantheistic emotion of worship when considering "the wonders of creation."

IDers hold that many elements of life around us imply specific interventions by the creator; while to a theistic evolutionist, the natural system is made all the more impressive as an act of creation due to its inherent sufficiency (a sufficiency gifted to it by God).

As far as all that goes, it seems both positions can be satisfying to a believer. (And I would add, it doesn't seem as if either position can claim full or final certainty, tho both can make fairly plausible arguments.)

[Josh]

Originally posted 7/11/06:

I sorta felt that Dembski's analogy above kind of meshed both of these views together- sort of having your cake (design in specific incidents) and eating it too (but not viewed as 'tinkering'- rather, part of the 'program').

[Josh]

Robin wrote:

I would be interested in seeing this evidence [for Common Ancestry]. From my understanding, this has become the default position for evolutionist because of the lack of evidence (transitional fossils).

Robin, just a thought or two on this.... The theory of common ancestry finds its support IMO in the genetic and anatomical relationships betwwen species and the general progress (though with significant gaps, there is progress) we find in the fossil record

I agree with you that the lack of transitional fossils between species A and B is a strong argument against naturalistic evolutionary processes (though Hume is more open to a throughly naturalistic process started by God in the beginning).

Evolutionists attempt to explain the gaps by theories like punctuated equilibrium, etc.. but I think at this point the best explanation is that God took one species and created another out of it. Another way of saying this would be that a species cannot transition to another species unless God miraculously intervenes (they naturally produce according to their kinds). I just don't think that the evidence points toward him making new species out of nothing. The similarities between earlier and later species, plus possible residual features that carry over from one species to another are arguments in favor of common ancestry to me.

How do you tend to explain these similarities between species?

[robin]

How do you tend to explain these similarities between species?

Which specific similarities are you speaking of? God created a world where if anything had any hope of living it would be required to have certain attributes. Rather than jumping to the conclusion that similarities point to common ancestry, I would say that they point to a common creator. What kind of distinct difference would you need to see in order to say that their is no common ancestry? What would such a species look like, and what attributes would they have?

Evolutionists attempt to explain the gaps by theories like punctuated equilibrium, etc.. but I think at this point the best explanation is that God took one species and created another out of it.

Yes Josh, but this only exists as a theory. There is no evidence for it. In fact the best argument for it is that there is no evidence. Does this make sense? Am I to assume that in theory a dog may have given birth to a fully developed cat? This requires an immense amount of faith. More than I have.

I just don't think that the evidence points toward him making new species out of nothing.

Why not? Your theory must at least require that God created the first specie out of nothing, correct? Why would god not create all species at one point? If fact it would almost be required in order to have balance in the Eco system. Remove honey bees from our Eco system and see what happens to our crops. It would be devastating.

The similarities between earlier and later species, plus possible residual features that carry over from one species to another are arguments in favor of common ancestry to me.

I'm sorry Josh, but perhaps you should read this sentence over again and see if you would like to re-state it. I believe you are at fault for using circular reasoning.

Robin

[Josh]

Rather than jumping to the conclusion that similarities point to common ancestry, I would say that they point to a common creator.

Yes, your reasoning has been discussed further up the thread. It has merits. But the logic runs both ways- a designer can reuse a good design in two ways- take the blueprints (that exist only in the mind of the designer) and remake a new model from scratch or add to or modify an already existing model.

Yes Josh, but this only exists as a theory. There is no evidence for it. In fact the best argument for it is that there is no evidence. Does this make sense? Am I to assume that in theory a dog may have given birth to a fully developed cat? This requires an immense amount of faith. More than I have.

We are both describing the miraculous, of course. I'm not wholly closed to the idea of God creating new species out of nothing, but I have a fair amount to say as to why I don't think that's what happened (why I think there is some degree of evidence for common ancestry) It's true, so far on this thread CA has been largely assumed- but I think that's just because both Hume and I started with that prior agreement. I'll work on a statement of what I believe to be some positive evidence for the TCA, but for now, a couple remarks:

From this point of view, I don't envision one species in one generation "giving birth" to a completely different species.

I envision gradual miraculous changes over a short time period (thousands or hundreds of thousands of years) from one species to a largely similar but distinct species.

Also, I don't see why the dog to cat example requires more faith than God creating out of thin air. They both seem outlandish but very possible knowing God. You're right, though, the creation of the first living thing must have been ex nihilo, so there can't be any a priori rejection of creation out of nothing. It's more a matter of ascertaining where the evidence best leads us.

More on that later...

Why exactly do you think my last statement is circular reasoning?
Aren't we both agreed with the premises that there are similarities between species (and possibly residual features*)? Can't such similarities be used as evidence (though not proof) that such species are physically related?

* okay, I realize residual features might be a hard sell at this point, so we can drop that if need be.

[Josh]

Also, it just occurred to me, that the age of the universe/ earth is intrinsically bound up into this discussion.

From your current perspective, do you see the creation days as 24 hour periods? Do you think that God created every species of animal that ever existed during a 48 hour period with no inter-species change since then?

Part of the argument in favor of common ancestry depends upon fossil evidence of the appearance of new species over millions of years, so it's important that we state more of our premises.

[robin]

From your current perspective, do you see the creation days as 24 hour periods? Do you think that God created every species of animal that ever existed during a 48 hour period with no inter-species change since then?

Yes, this is my position.

[robin]

Part of the argument in favor of common ancestry depends upon fossil evidence of the appearance of new species over millions of years, so it's important that we state more of our premises.

We must also look at whether it is more likely that the fossil record we have is evidence of the progression of animal life over millions of years, or the result of one cataclysmic event (worldwide flood) that provides a snapshot of species that lived at on point in time.

Robin

[Josh]

Exactly.

So, there are two threads that already discuss the age of the earth/ universe:

How Long Were the Creation Days?

and

Life on Other Planets/ Age of the Universe

Jump in on either of those, or maybe after taking a look there you might want to start a new thread on Catastrophism vs. Gradualism or something like that?

[robin]

From this point of view, I don't envision one species in one generation "giving birth" to a completely different species.

I envision gradual miraculous changes over a short time period (thousands or hundreds of thousands of years) from one species to a largely similar but distinct species.

Your view of a "short period of time" seems rather odd from my perspective. Recorded human history only goes back 6000 years or so. Given your theory on "thousands or hundreds of thousands of years" would we not still have transitional humans or at least have some record of them ever existing. But lets say that it would take between 50,000 and 100,000 years for a transformation to take place. Would this not create a wealth of transitional fossils? If the average generation is say 50 years, and that is generous given the life expectance of many species, that would provide 1000 to 10,000 generations within the fossil record, and this process would have to be repeated thousands upon thousands of times over given the vast number of know species that have existed. Yet the absence of any such fossils is striking.

Robin

[Josh]

Well, a couple things:

The fossil record is spotty and incomplete, so to find transitional fossils from millions of years ago over so short of a geological time period could be difficult. (I wasn't primarily thinking about more recent hominids here). But if you're talking about the last 100,000 years, it does seem like according to my hypothesis we would see more incrimental transitional forms.

I have to say that the whole common ancestry thing is sketchy to me, admittedly. I'll try and post my reasons for suspecting it soon. But before I considered the possibility of God "morphing' one species into another in some way, I was pretty firmly an "old-earth" "progressive" "special-creationist".

You've probably heard of Dr. Hugh Ross and reasons to believe. That's their position- old earth, progressive creation, but creation of new species ex nihilo.

I feel a lot more convinced that the earth and universe are old and that God created over a period of millions of years than I am of either a) the fact of common genealogical ancestry or, especially b) any theory I have as to how God may have changed one species into another.

Perhaps another way of envisioning God using the raw material of one species to create another would simply be to imagine him miraculously and instantaneously changing one species into another relatively similar species. This is basically identical to the idea of God creating an animal out of thin air, but would be [perhaps] a better way of accounting for genetic and morphological continuity.

Actually, now that I think of it, don't those who hold to a "young earth" even argue that God did something similar in creating Adam (and the animals): Adam wasn't truly created ex nihilo, he was formed of pre-existent material- ie, dust.

Others between the spectrum of progressive creationism and theistic evolution might interpret the reference to the dust of the earth as a nod to common geneological ancestry, but still, wouldn't all the camps actually have to concede either way that God did use pre-existant physical material to make new species?

Also, Robin, I'm assuming here that we see this discussion as an "in-house" debate well under the "pale of christian orthodoxy"?*



* inward groan at the need to quote the Bible Answer Man

[robin]

Also, Robin, I'm assuming here that we see this discussion as an "in-house" debate well under the "pale of christian orthodoxy"?*

No! Your a heretic, and will burn in hell for this belief. Of course I'm joking ;D. I think its great that we can disagree on such matters without being offended.

Robin