THE THIRD WAVE
As the Third Wave dawns, our own planet seems much smaller and more vulnerable. Our place in the universe seems less grandiose. And even the remote possibility that we are not alone gives us pause.
Our image of nature is not what it used to be.
DESIGNING EVOLUTION
Neither is our image of evolution—or, for that matter, evolution itself.
Biologists, archaeologists, and anthropologists, attempting to unravel the mysteries of evolution, similarly find themselves in a bigger and more complex world than previously imagined and are discovering that laws once regarded as universal in application are actually special cases.
Says the Nobel Prize-winning geneticist Francois Jacob, “Since Darwin, biologists have gradually developed a … chart of the mechanism of evolution, called natural selection. On that basis attempts have often been made to portray all evolution—cosmic, chemical, cultural, ideological, social—as governed by a similar selection mechanism. But such understandings seem doomed, inasmuch as the rules change at every plane.”
Even on the biological plane, rales once thought to apply across the board are in question. Thus scientists are being forced to ask whether all biological evolution is a response to variation and natural selection or whether, at the molecular level, it may depend instead on an accumulation of variations which result in “genetic drift” without the operation of Darwinian natural selection. Says Dr. Motoo Kimura of the National Institute of Genetics in Japan, evolution at the molecular level appears to be “quite incompatible with the expectations of neo-Darwmism.”
Other long held assumptions are being shaken as well. Biologists have told us that eukaryotes (human beings and most other forms of life) are ultimately descended from simpler cells called prokaryotes (among which are bacteria and algae) . Fresh research is now underminingthat theory, leading to the unsettling notion that the simpler life forms may have descended from the more complex.
Furthermore, evolution is supposed to favor adaptations that enhance survival. Yet we are now finding striking examples of evolutionary developments that seem to confer long-term benefit—at the cost of short-term disadvantage. Which does evolution favor?
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