No. 116: Mar-Apr 1998
Epigenetic phenomena -- those phenomena beyond the pale of DNA -- are seen in "diffuse individuals" such as fungi, where it is difficult to separate individual units of life. To illustrate, some fungi may be 1,000 years old and extend for 35 acres (15 hectares) and yet possess a single, still unmodified genome. In his review of A. Rayner's new book Degrees of Freedom: Living in Dynamic Boundaries, T. Wakeford writes:
"So, like the World Wide Web, a fungal network is decentralized. There is no central region capable of exerting control over the rest of the network. Rayner's own work suggests that the growth patterns of fungal filaments are forged as much by the environment that they encounter as by their genes. He believes that epigenetics, the process whereby opportunities in an organism's surroundings dictate which genes are expressed, is the norm in microorganisms. Genetic determinism is thus turned on its head."
(Wakeford, Tom; "We Are the Fungus," New Scientist, p. 49, May 10, 1997.)
Comment. Looking at the above situation from an information viewpoint, as one must these days, it seems that the environment can somehow "interpret" genes as the situation demands. In other words, genes are not "single-message" information carriers, but can be "read" in different ways according to the environment encountered by their "carriers"; that is, the organisms that bear them. Is this how "adaptive evolution" works?
If it is, the genome must contain a multitude of "contingency plans" because the environment by itself cannot add a new suite of capabilities to the genome; it can only trigger what is already there! But maybe there is something we are missing in all this.