Why ID Argues Against Common Descent?

Continuing the discussion from Side Comments on Nelson's Signal + Noise:

It seems to be a social contract, a political bargain,

  1. Those that affirm Common Descent (CD) are welcome in ID, and will be accepted there. Everyone within ID will focus on the common ground.

  2. Those that affirm CD in ID, however, will not emphasize the case for CD, nor will they dispute arguments made against CD by others in ID.

  3. ID proponents that dispute CD will publicly argue against CD, but they will not take ID proponents that support CD to task on this.

  4. If the debate against CD gets too contentious and fixated, someone at ENV will reassure everyone that CD is compatible with ID, begging the question of why DI spends any time arguing against it at all.

All this bears the marks of a political balancing act they are playing between different factions, holding together a coalition divided on this issue. What is your take @pnelson, @Agauger, and @Kirk?

From a scientific point of view, it seems like a better strategy would be to ditch the arguments against UCD. I’m not sure what it buys you within science. Whether or not UCD is correct, it does not tell us anything about ID. If ID is true, it does not tell us anything about UCD. If ID is really neutral with respect to common descent, it would make most sense if you (ID) were as careful about avoiding arguments against CD as you have been against connecting the “designer” to “God.”


You are right, we are a coalition of individuals with different backgrounds, religious persuasions, and kinds of scientific understanding. Some of the reasons for arguing against CD are religious, though certainly not all are. Arguments against UCD are pretty much evidence based. There is lively debate within ID, and a consistent effort to maintain unity on what we consider the main point, i.e. the necessity of design as an explanation for life.

We don’t have a message minder, or one universal source of material. Just about anyone who reads can declare himself an ID theorist. You can’t get a PhD in ID, or require an ID driver’s license. If many ID supporters doubt UCD or CD, you can pretty much expect that signal to appear in the overall broadband message.

You are also right. It wouldn’t matter if we all became UCD supporters overnight. It hasn’t helped Behe.


It seems to me that ID is defined by two things: scientific detectability of design and anti-evolutionary arguments (of various kinds). I believe that if ID had chosen to never engage in the latter, they would have had much less political backlash in general.


As a YEC i agree with Ann Gauger’s point about diversity in backgrounds.
Its really just the tradition finding of God fingerprints in nature and that apparent. From this a rejection of chance encounters of this and that to create the glory of complexity and diversity in nature.
Those who reach the biggest audiences mostly have no problem with evolutionism/common descent within boundaries. Some have complaints or rejections of evolutionism and friends.
They became famous because they did a excellent job of reaching audiences. THEN the establishment noticed well degree ed ID thinkers and saw them as a threat as leaders of creationism. Creationism being popular already and this meaning christian, historic american Protestantism, foundations are alive and well.
SO the bad guys attack ID as creationists, which helps YEC credibility,
YEC great numbers hear about iD thinkers and so read their stuff thinking bit helps creationism. SO ID gain.
However its a cast of characters and one needs a playbook to keep up.

I agre with ANG that iD about scientific detectability of design. For some but not all anti evolutionary arguments in this or that conclusion.
Anyways ID, YEC less so but also, are the most important innovative criticisms of important to have come into western science in decades. They already will be a studied historical movement in science and if win will be greatly studied. so get your autographs including folks who visit here at Peaceful Science.


This quote from Dr. G. to Dr. @swamidass seems conclusive that Behe and Dr. G. do not affirm the same principles.


??? You read entirely too much into what I said. I do affirm the same principles, bar one. UCD. And I don’t know personally where Behe stands, whether UCD or CD. I know he affirms CD. I spoke too loosely there.

1 Like

That is how I understand it. @Agauger, this is somewhat news to me about you. Are you saying that you affirm UCD?

No I do not.

1 Like

If the second sentence refers to me, I challenge UCD because I think the assumptions and arguments in support of the theory are much weaker than most biologists realize, and therefore biology (as a science) suffers because of it. I would challenge UCD even if I wasn’t an ID theorist.

What many contributors here seem not to realize is the fact that many leading evolutionary biologists, who totally oppose ID, are skeptical of UCD. Today I have lectures to give at Louisiana College, so I can’t go into the topic in any depth, but doubts about UCD, historically and today, do not equate to support for ID or “creationism.” In short, the dimensions of the playing field on this topic are not confined to two poles. At least four positions have been, and are, well occupied by prominent scientists (the familiar ones are no ID and UCD, ID and no UCD; less familiar, but quite real: ID and UCD, no ID and no UCD).

I find this to be a very surprising statement and I think some evidence is needed to support this claim.

Any one who wonders if there is life on other solar systems doubts UCD.

Any one who wonders if there was more than one origin of life on earth doubts UCD.

Which is, once again, why I’m doubtful of the relevance of this to anything. UCD is not a foundational claim of biology, or we would not be looking for life on other planets.


What? Why? There could be life on other planets and UCD still be true on our planet.

And how many biologists actually think this is a real possibility? I find multiple origin of life’s extremely unlikely. If there was a second origin of life it would be outcompeted by the already existing life and go extinct fairly quickly. I don’t know of any leading evolutionary biologists who doubt UCD here on earth

TJ wrote:

“I don’t know of any leading evolutionary biologists who doubt UCD here on earth”

This paper is open access:

The accuracy of the common origin and the relevance of the tree-like representation as a model of evolution have been frequently questioned (Bapteste et al., 2009; Dagan and Martin, 2009; Puigbo et al., 2010). The TOL concept presumes that all organisms are descended from a predecessor. This is true for a number of genetic sequences but not for some ORFans, including the functional ORFans. Indeed, some genes and proteins have been entirely invented in the last million years. For example, genes that are specific to the species of Drosophila , have been demonstrated to be essential, or at least useful, for the current life of Drosophila (Chen et al., 2010). These genes originated in an ancestor of Drosophila for which they were useful, but they were never created elsewhere. The TOL is a perception of conservative nature that lost the ability to create anymore new function since the ancestor was alive. This is contrary to our current knowledge. The analysis of bacterial genomes shows that between 10 and 15% of the genes of each species has no equivalent in other species (p. 12, emphasis added)

This paper, now a classic which has been cited 493 times, is also open access:

“Darwin claimed that a unique inclusively hierarchical pattern of relationships between all organisms based on their similarities and differences [the Tree of Life (TOL)] was a fact of nature, for which evolution, and in particular a branching process of descent with modification, was the explanation. However, there is no independent evidence that the natural order is an inclusive hierarchy, and incorporation of prokaryotes into the TOL is especially problematic.”

1 Like

TJ, there is additional evidence about evolutionary biologists who doubt UCD in my chapter on UCD (chapter 12) in the Theistic Evolution anthology, which you should have received from Amazon last Friday.

1 Like

Thanks, Paul! I just took it out of the box.

1 Like

I think your four point list nailed it. I think we’ve all been noticing these four tendencies for years, even if we rarely pause to summarize them so succinctly.

Of course, reason ENV spends so much time denying evolution is because it attracts website traffic (and, ultimately, donors and book buyers.) [I’m not saying there’s anything wrong with wanting high traffic and book sales. I’m just saying that I’m not surprised ENV has a strategy which doesn’t often remind anti-evolution visitors that many of the Discovery Institute scientists affirm evolutionary processes.]

I know many evolution deniers who cite the Discovery Institute scientists as among the authorities who support their denial of everything related to the Theory of Evolution. Many of them assume that ID is the antonym of evolution.

1 Like

I believe this is a correct description of how Discovery’s position is frequently understood. However, it is hard to square this inference with (a) explicit statements on the Discovery website (on the pages where ID is defined) that make clear that ID is not in principle opposed to common descent; (b) Mike Behe’s place as a major ID theorist and Discovery Fellow since the beginning of Discovery’s involvement with ID; © the fact that in the past two years Discovery has published FOUR (4) books by Michael Denton, who affirms common descent. It is as if some people take from Discovery only what they want to hear, and ignore the rest.

I’ve always understood Discovery’s position to be: “All of us affirm that design is necessary to explain the arrangements of nature. Some of us accept common descent, some of us don’t, and some of us are uncertain about it. Acceptance or rejection of common descent is not a criterion for determining ‘membership’ in the ID movement.” I can understand why this laissez-faire position might not be satisfying to those biologists who think that common descent is as certain as the laws of gravity, but I don’t think that it’s unclear.

1 Like

@pnelson I don’t understand why you think this quote helps you. Many people who question the TOL are just asserting that there was a lot of horizontal gene transfer, especially at the base of the tree. This has nothing to do with denying UCD, but rather with pointing out that the tree is tangled so much as to be non-tree-like.


That was my first thought as well. Thinking the tree may be more like a web doesn’t mean you doubt UCD.

1 Like

Let’s take a look at that paper, shall we?