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Leading Biologists Marvel at the “Irreducible Complexity” of the Ribosome, but Prefer Evolution-of-the-Gaps

Casey Luskin

A roundtable symposium was recently held at by John Brockman entitled, “Life: What A Concept!” discussing how life arose. Participants included some huge names in origin of life research and genomics, such as Freeman Dyson, J. Craig Venter, George Church, Robert Shapiro, Dimitar Sasselov, and Seth Lloyd. None of the participants are favorable towards intelligent design, but the transcript of their conversations suggested that the ribosome may exhibit “irreducible complexity” (their words). It’s clear that these anti-ID scientists don’t even understand exactly how life works, much less do they know how it arose naturally, but that they are nonetheless taking an evolution-of-the-gaps approach, assuming that complex micromolecular machines like the ribosome will (despite their present appearances) indeed turn out to be reducible, and assuming that they evolved in a step-by-step fashion. Craig Venter, a leader in genomics and the Human Genome Project, stated:

We talked about the ribosome; we tried to make synthetic ribosomes, starting with the genetic code and building them — the ribosome is such an incredibly beautiful complex entity, you can make synthetic ribosomes, but they don’t function totally yet. Nobody knows how to get ones that can actually do protein synthesis. That is not building life from scratch but relying on billions of years of evolution.

So we don’t even know exactly how this organelle works, but we know that it has arose through “billions of years of evolution.” Soon thereafter in the conversation, George Church, Professor of Genetics at Harvard Medical School and Director of the Center for Computational Genetics, similarly marveled at the complexity of the ribosome:

The ribosome, both looking at the past and at the future, is a very significant structure — it’s the most complicated thing that is present in all organisms. Craig does comparative genomics, and you find that almost the only thing that’s in common across all organisms is the ribosome. And it’s recognizable; it’s highly conserved. So the question is, how did that thing come to be? And if I were to be an intelligent design defender, that’s what I would focus on; how did the ribosome come to be?

Church goes on to explain the difficulties faced by those trying to explain how the ribosome evolved:

The only way we’re going to become good scientists and prove that it could come into being spontaneously is to develop a much better in vitro system where you can make smaller versions of the ribosome that still work, and make all kinds of variations on it to do really useful things but that are really wildly different, and so forth, and get real familiarity with this really complicated machine. Because it does a really great thing: it does this mutual information trick, but not from changing something kind of trivial, from DNA to RNA; that’s really easy. It can change from DNA three nucleotides into one amino acid. That’s really marvelous. We need to understand that better.

Church seems stymied at attempts to explain the naturalistic origin of the ribosome. Craig Venter suggested that by sequencing the genomes of more organisms perhaps we could reconstruct a primitive precursor ribosome. But Church is skeptical that this is unlikely to help because current biology reveals that a minimum number of genes are required for a functional ribosome–and that minimum number is still quite large:

But isn’t it the case that, if we take all the life forms we have so far, isn’t the minimum for the ribosome about 53 proteins and 3 polynucleotides? And hasn’t that kind of already reached a plateau where adding more genomes doesn’t reduce that number of proteins?

The conversation that follows is striking, showing that as far as we know, the ribosome has “irreducibly complexity”:

VENTER: Below ribosomes, yes: you certainly can’t get below that. But you have to have self-replication.

CHURCH: But that’s what we need to do — otherwise they’ll call it irreducible complexity. If you say you can’t get below a ribosome, we’re in trouble, right? We have to find a ribosome that can do its trick with less than 53 proteins.

VENTER: In the RNA world, you didn’t need ribosomes.

CHURCH: But we need to construct that. Nobody has constructed a ribosome that works well without proteins.


SHAPIRO: I can only suggest that a ribosome forming spontaneously has about the same probability as an eye forming spontaneously.

CHURCH: It won’t form spontaneously; we’ll do it bit by bit.

SHAPIRO: Both are obviously products of long evolution of preexisting life through the process of trial and error.

CHURCH: But none of us has recreated that any.

SHAPIRO: There must have been much more primitive ways of putting together

CHURCH: But prove it.

In the end, Robert Shapiro’s statements said it all: We don’t know how the ribosome and its required proteins evolved, but we know that “Both are obviously products of long evolution of preexisting life through the process of trial and error.” This is a prime example of “evolution-of-the-gaps,” and it demonstrates that intelligent design could go a long way towards solving problems in 21st century biology. This also demonstrates that intelligent design proponents have worthwhile contributions to make and deserve a place at the table in these kinds of discussions.


Casey Luskin

Associate Director, Center for Science and Culture
Casey Luskin is a geologist and an attorney with graduate degrees in science and law, giving him expertise in both the scientific and legal dimensions of the debate over evolution. He earned his PhD in Geology from the University of Johannesburg, and BS and MS degrees in Earth Sciences from the University of California, San Diego, where he studied evolution extensively at both the graduate and undergraduate levels. His law degree is from the University of San Diego, where he focused his studies on First Amendment law, education law, and environmental law.



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