Darwin's Doubt by Stephen C. Meyer

Author:Stephen C. Meyer
Language: eng
Format: epub
Publisher: HarperCollins
Published: 2013-04-28T16:00:00+00:00

Order vs. Information

Self-organizational theorists face, in addition, a conceptual distinction that has cast doubt on the relevance of their theories to biological systems. Self-organizational theorists seek to explain the origin of “order” in living systems by reference to purely physical or chemical processes (or laws describing those processes). But what needs to be explained in living systems is not mainly order in the sense of simple repetitive or geometric patterns. Instead, what requires explanation is the adaptive complexity and the information, genetic and epigenetic, necessary to build it.

Yet advocates of self-organization fail to offer examples of either biological information or complex anatomical structures arising from physics and chemistry alone. They either point, as Newman and Kauffman do, to embryological development unfolding predictably as the result of preexisting information-rich gene products, cell membranes, and other cell structures. Or they offer examples of purely physical and chemical processes generating a kind of order that has little relevance to the features of living systems that most need explanation.

In the latter case, self-organizational theorists often point to simple geometric shapes or repetitive forms of order arising from or being modified by purely physical or chemical processes. They suggest that such order provides a model for understanding the origin of biological information or body-plan morphogenesis.41 Self-organizational theorists have cited crystals, vortices, and convection currents (or stable patterns of flashing lights) to illustrate the supposed power of physical processes to generate “order for free.” Crystals of salt do form as the result of forces of attraction between sodium and chloride ions; vortices can result from gravitational and other forces acting on water in a draining bathtub; convection currents do emerge from warm air (or molten rock) rising in enclosed spaces. And some molecules found in living systems do adopt highly ordered structures and recognizable geometric shapes as the result of the physical interactions of their constituent parts alone. Nevertheless, the type of order evident in these molecules or physical systems has nothing to do with the specific “order” of arrangement—the information or specified complexity—that characterizes the digital code in DNA and other higher-level information-rich biological structures.

This is easiest to see in the case of the information encoded in DNA and RNA. Some of what follows may be familiar from my discussion in Chapter 8, but it bears repeating. The bases in the coding region of a section of DNA or in an RNA transcript are typically arranged in a nonrepetitive or aperiodic way. These sections of genetic text display what information scientists call “complexity,” not simple “order” or “redundancy.”

To see the difference between order and complexity consider the difference between the following sequences:

Na-Cl-Na-Cl-Na-Cl-Na-Cl

AZFRT<MPGRTSHKLKYR

The first sequence, describing the chemical structure of salt crystals, displays what information scientists call “redundancy” or simple “order.” That’s because the two constituents, Na and Cl (sodium and chloride), are highly ordered in the sense of being arranged in a simple, rigidly repetitive way. The sequence on the bottom, by contrast, exhibits complexity. In this randomly generated string of characters, there is no simple repetitive pattern.

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