Review: Darwin's Radio by Greg Bear
In evolutionary debate, the question of Intelligent Design is a hot button; if life-forms are evolving to a particular design, one must presuppose a designer.
We also need a mechanism to communicate the design, one that matches observed phenomena better than Darwinian selection, and can carry design instructions forward through generations of forms that do not express it. For example, if a design is responsible for an air-breather's lungs, there must be some way for a genetic instruction for lungs to reside in the gill-breathing precursor—and that instruction must stay unexpressed through aeons of gill-breathers.
Greg Bear has proposed such a mechanism in Darwin's Radio. Biologist Kyle Lang is investigating the possibility that an ancient disease may be coiled "like a sleeping dragon" in the remnants of endogenous retroviruses, the so-called "junk DNA" in the human genome. As her research begins to bear fruit, a pandemic is growing. If she does not act, soon there may not be any humans left to use the knowledge she has gained.
Bear has taken a fact: the existence of gene "phages" that lie unexpressed in the genetic code until environmental stress causes them to express, and which can lie dormant for generations until they find the right conditions to express. From that fact, Bear has taken a giant "what if" leap: What if a similar DNA sequence lies unexpressed in human DNA, waiting to drive all of us in the next evolutionary step forward?
Even though there is a potential mechanism for communicating a genetic design forward through time, unaddressed in this novel or its sequel Darwin's Children is the question of Intelligent Design itself. In fact, the second book seems to imply the opposite, that the "radio" which is telegraphing messages forward is merely genetic selection at the level of the individual gene.
So although the books are thrilling, and chock-full of information about human DNA research skillfully used to drive the story, for me, there is that nagging question still waiting to be asked.