Sidebar...

I often wonder what life would be like on this planet if it hadn't experienced so many huge extinction events. If the Cretaceous-Tertiary Extinction Event hadn't wiped out the dinosaurs, we mammals would probably have remained small rodents scurrying through the underbrush. Modern paleontologists believe some smaller, warm-blooded dinosaurs were good candidates for evolving into creatures not all that dissimilar to ourselves. If the evolutionary time-clock hadn't been reset at that extinction event, it's likely that the time-span for "intelligent life" on this planet would be measured in tens of millions of years, instead of merely tens of thousands.

So, if its conceivable that this planet could have hosted an intelligent species unimaginably more advanced than our own, and given a universe with an infinite number of planets, who knows what might have evolved elsewhere?