The Origin of Biological Information
Steven Meyer - The Origin of Biological Information and the Higher Taxonomic Categories
In the recent volume of the "Vienna Series in Theoretical Biology," Gerd B. Muller and Stuart Newman argue that what they call the "origination of organismal form" remains an unsolved problem. In making this claim, Muller and Newman distinguish two distinct issues, namely, (1) the causes of form generation in the individual organism during embryological development, and (2) the causes responsible for the production of novel organismal forms in the first place during the history of life. Neo-Darwinism lacks any "theory of the generative." G. L.G. Miklos argued that neo-Darwinism fails to provide a mechanism that can produce large-scale innovations in form and complexity. Microevolution looks at adaptations that concern the survival of the fittest, not the arrival of the fittest. (Darwin’s Nemesis p. 174-75)
The Cambrian explosion refers to the geologically sudden appearance of many new animal body plans about 530 million years ago. At this time, at least nineteen and perhaps as many as thirty-five phyla of forty total make their first appearance on earth within a narrow five-to ten-million year window of geological time. Many new subphyla, between thirty-two and forty-eight of fifty-six total, and classes of animals also arose at this time with representative of these new higher taxa manifesting significant morphological innovations. (Darwin’s Nemesis p. 176)
Studies of modern animals suggest that the sponges that appeared in the late Precambrian period, for example, would have required five cell types, whereas the more complex animals that appeared in the Cambrian (e.g., arthropods) would have required fifty or more cell types. New cell types require many new and specialized proteins. New proteins, in turn, require new genetic information.
New proteins are required to service new cell types. But new proteins must be organized into new systems within the cell; new cell types must be organized into new tissues, organs and body parts. These in turn must be organized to form body plans. Such hierarchical organization itself represents a type of information, since body plans comprise both highly improbable and functionally specified arrangements of lower-level parts. (Darwin’s Nemesis p. 180-81)
Some scientists have argued that alterations in sequencing would likely result in loss of protein function before a fundamentally new function could arise. Studies of proteins have long shown that amino acid residues at many active positions cannot vary without functional loss. (Darwin’s Nemesis p. 182)
New Cambrian animals would require proteins such as Lysyl oxidase in order to support their stout body structures. Lysyl oxidase in extant organisms comprise over four hundred amino acids. These molecules are both highly complex and functionally specified. Reasonable extrapolation from mutagenesis experiments done on shorter protein molecules suggests that the probability of producing functionally sequenced proteins of this length at random is so small as to make appeals to chance absurd, even granting the duration of the entire universe. New cell types require systems of proteins that must, as a condition of functioning, act in close coordination with one another.
The sensitivity of proteins to functional loss, the need for long proteins to build new cell types and animals, the need for whole new systems of proteins to service new cell types, the probable brevity of the Cambrian explosion relative to mutation rates-all suggest the immense improbability of any scenario for the origination of Cambrian genetic information that relies on random variation alone unassisted by natural selection. (Darwin’s Nemesis p. 184-85)
Evolving genes and proteins will range through a series of nonfunctional intermediate sequences that natural selection will not favor or preserve but will, in all probability, eliminate. We must account not only for new proteins and cell types but also for the origin of new body plans. Significant morphological change in organisms requires attention to timing. Mutations in genes that are expressed late in the development of an organism will not affect the body plan. Mutations expressed early in development however, could conceivably produce significant morphological change. A paradox arises here. According to J. F. McDonald, mutations of the kind that macroevolution doesn't need (expressed later in development) do occur, but those that it does need (expressed early in development) do not occur. There is evidence that variations which favor body plan development-never occur. (Darwin’s Nemesis p. 187-88)
Developmental biology has raised another formidable problem for the mutation/selection mechanism. Embryological evidence has long shown the DNA does not wholly determine morphological form, suggesting that mutations in DNA alone cannot account for the morphological changes required to build a new body plan. DNA alone does not determine how individual proteins assemble themselves into larger system of proteins, still less does it solely determine how cell types, tissue types and organs arrange themselves into body plans. Instead, other factors-such as the three-dimensional structure and organization of the cell membrane and cytoskeleton and the spatial architecture of the fertilized egg-play important roles in determining body plan formation during embryogenesis. (Darwin’s Nemesis p. 188)
By invoking design to explain the origin of new biological information, contemporary design theorists are not positing an arbitrary explanatory element unmotivated by a consideration of the evidence. Instead, they are positing an entity possessing precisely the attributes and causal powers that the phenomenon in question requires as a condition of its production and explanation. (Darwin’s Nemesis p. 203)
(Excerpted from Darwin’s Nemesis, William Dembski, Editor)
Stephen C. Meyers has a Ph.D. from the University of Cambridge in the History and Philosophy of Science.
William A. Dembski has a Ph.D. in philosophy, a Ph.D. in mathematics and a M.S. in Statistics from the University of Chicago. He also has a M. Div. degree from Princeton Theological Seminary.
Compiled by Ed Hopkins. Ed is a science educator with 32 years of experience teaching science. Ed has an undergraduate degree in chemistry and biology from George Peabody Teacher’s College, TN and a M.Ed. from Atlantic University, FL. Ed has been working closely with the Creation Studies Institute, Ft. Lauderdale, FL since its inception in 1988.