The Cambrian Explosion and Intelligent Design – Part 3
Dr. John Ankerberg: In this clip we’re going to show that the body plan for an animal does not reside in DNA. So where is the information of each animal body plan stored, and where did that information come from? Folks, I want you to watch this clip. Read on to learn more about the Cambrian Explosion
Narrator: But the inability of random mutations to generate new genes and proteins is only part of the problem; for the origin of Cambrian body plans demanded more than new genetic information.
Richard Sternberg: A lot of the information for specifying an Anomalocaris, a trilobite, what have you, does not reside at the DNA level.
Jonathan Wells: The body plan, as far as we know, is not in the DNA.
Narrator: While DNA carries the instructions to manufacture proteins, it cannot alone assemble them into cell types, or arrange cell types into new tissues and organs, or tissues and organs into body plans. Instead, the formation of body plans ultimately requires another level of information stored somewhere in the three-dimensional structure of the egg cell and the embryo; instructions that direct the development of complex animals from fertilized eggs. With computer animation we can observe this intricate process. As an egg cell begins to divide and differentiate, a network of biological commands orchestrates the development of an arthropod. After several stages of division, dozens of new cells align against the outer membrane of the egg. And then, cued by a chemical signal, they start their migration toward targeted areas in the embryo where they will gather and develop into a mature organism. The cells steadily increase their numbers, and align, like members of a marching band, into patterns that will form the tissues and organs, head and legs of the growing embryo.
Paul Nelson: That happens by a process of cell specification and differentiation, where cells are committed irreversibly to performing particular roles. You’re going to give them different jobs to do: You’re going to be a part of the locomotory system of this organism; you’ll be an eye; you’ll be a gut; and so forth. To me that’s an absolutely astonishing process, but it works. And what it builds you is different kinds of organisms, depending on the instruction set that’s provided.
Richard Sternberg: So there is an organismal blueprint, an ultimate point that the embryo hones in on and is attracted to, and eventually embodies.
Jonathan Wells: That foresight, that preordained outcome, is built into the embryo.
Richard Sternberg: When you talk about these early developmental sequences, an Anomalocaris, an Opabinia, what have you, you’re talking about information in the broad sense, codes, specifications, entailments, implications, that are orders of magnitude beyond anything that we can currently conceive. It’s so off-scale that you’ve left that line of impossible by chance a long time ago.
Narrator: The volume and complexity of information that controls the development of a body plan is staggering. And its location in the cell stands as perhaps the ultimate challenge to the neo-Darwinian scenario of random mutation and natural selection.
Stephen Meyer: We know that much of this higher level information that’s required for building new tissues and organs and body plans isn’t found in DNA. That means that you can mutate DNA indefinitely without respect to probabilistic limits, without respect to time and number of trials, and you’re never going to get the kind of form and structure you need to build a new organism. DNA is simply the wrong tool for the job; and no amount of time is going to overcome that limitation. That has a really devastating implication for the Neo-Darwinian mechanism.
Narrator: If the Darwinian mechanism cannot explain the origin of the information necessary to produce the Cambrian animals, is there any other cause that can?
Dr. John Ankerberg: So, Dr. Meyer, help us understand this a little bit more.
Dr. Stephen Meyer: This last problem that we saw explained in the film is really a very profound and fundamental problem in modern biology. According to neo-Darwinism, new form arises as a result of new variations. And the new variations occur as a result of mutations in the DNA. So the ultimate source of new biological form are changes in the arrangement of those A, C’s and G’s in the DNA molecule.
But what developmental biologists are learning is that DNA is only part of the story. It provides a necessary amount of information for building proteins, but that information is nowhere sufficient to build a whole animal, because the proteins have to be arranged into structures within cells. Different types of cells have to be arranged to form tissues. Different tissues have to be arranged to form organs. And organs and tissues need to be arranged to form whole body plans or architectures, where a body plan is a unique arrangement of body parts and tissues. So DNA is necessary, but not sufficient.
Now, if we think of that in light of what neo-Darwinism says, it says that the source of new form and structure in a biological system, in the new body plan, is going to come from variations in the DNA. But if the DNA only provides the information for building proteins, and other levels of information are necessary to arrange the proteins, the cell types, the tissues, and the organs into a whole body plan, then you could mutate DNA indefinitely and you will never build a new organism. The technical way of saying that is, if body plan building or body plan morphogenesis depends on information beyond DNA, then mutating DNA is never going to get you a new body plan. It’s not the right tool for the job.
Now, I first learned about this in a technical book published in 2003 by MIT Press that was co-edited by two leading evolutionary biologists. And in the introductory article to this book, in which they explained this problem of the higher levels or the epigenetic information, they acknowledged that neo-Darwinism was still the standard textbook theory, but they said that neo-Darwinism has no theory of the generative. That is to say, it can’t explain the big changes in the history of life; it doesn’t explain the origin of body plans.
Now, one of the things that struck me about reading that book and the many articles that were elucidating the difficulty of this problem, is that there’s a huge disparity between the public presentation of the status of evolutionary theory as we find it in our biology textbooks, as we find it presented by people like Bill Nye the Science Guy, or by Richard Dawkins, or by defenders of the Darwin-only approach to science education, on the one hand, and the actual status of evolutionary theory as we find it in the peer-reviewed technical literature in evolutionary biology, where many evolutionary biologists are now saying very openly that neo-Darwinism is dead, and we need to find a new theory of evolution.
And so one of the things I did in my new book, Darwin’s Doubt, is first of all, I exposed this disparity and showed that, you know, the popularizers are out of date and what they’re telling the public is simply false. And I also looked at the many new theories of evolution that are being proposed to replace neo-Darwinism. I examined them and then also critiqued them and showed that they too fail to explain the origin of the genetic information in DNA that you would need to build Cambrian animals, but also this higher level, epigenetic information.
And so there really is a crisis in evolutionary theory today, one that started way back in 1859 when Darwin honestly acknowledged the problem of the Cambrian explosion. But in the book I show that that problem has become much deeper and more profound as we’ve learned more about what it takes to build an animal. We need both genetic and epigenetic layers of information, and there is no evolutionary model today that accounts for the origin of that crucial information, and therefore the origin of these Cambrian animals.
Excerpted from our series The Case for Intelligent Design. See in our store at https://jashow.org/resources/the-case-for-intelligent-design/
