The issue, as correctly emphasized by Carl Sagan, is the probability of the evolution of high intelligence and an electronic civilization on an inhabited world. Once we have life (and almost surely it will be very different from life on Earth), what is the probability of its developing a lineage with high intelligence? On Earth, among millions of lineages of organisms and perhaps 50 billion speciation events, only one led to high intelligence; this makes me believe in its utter improbability.

Given the fact of evolution, one would expect the fossils to document a gradual steady change from ancestral forms to the descendants. But this is not what the paleontologist finds. Instead, he or she finds gaps in just about every phyletic series.

I had found again and again that the most aberrant population of a species - often having reached species rank, and occasionally classified even as a separate genus - occurred at a peripheral location, indeed usually at the most isolated peripheral location.

I have the honesty to say I'm an Atheist. There is nothing that supports the idea of a personal God.

Indeed, I was unable to find any evidence whatsoever of the occurrence of a drastic evolutionary acceleration and genetic reconstruction in widespread, populous species.

The issue, as correctly emphasized by Carl Sagan, is the probability of the evolution of high intelligence and an electronic civilization on an inhabited world. Once we have life (and almost surely it will be very different from life on Earth), what is the probability of its developing a lineage with high intelligence? On Earth, among millions of lineages of organisms and perhaps 50 billion speciation events, only one led to high intelligence; this makes me believe in its utter improbability.

New gene pools are generated in every generation, and evolution takes place because the successful individuals produced by these gene pools give rise to the next generation.