Good science fiction should be based on science fact.

Fact: Two years ago, scientists in Antarctica discovered a living bacterium believed to be about two hundred and fifty million years old.

By comparison, the villain in this story is a mere sixty five million years old.

Extinction hypotheses:

Were the dinosaurs wiped out in a cosmic collision? We know that a very large meteor struck an area now called the Yucatan around sixty five million years ago. We also know that a mass extinction occurred somewhere near this time frame, because we have carbon dated many pieces of the fossil record. Seems like an open and shut case, doesn’t it? On the other hand, carbon dating doesn’t give us really precise results. The half-life of carbon 14 is 5568 (±30) years. Using the assumed extinction timeline(65 million years ago), simple arithmetic yields plus or minus 350,000 years, giving us a window of 700,000 years during which the mass extinction must have occurred. Just a moment on the cosmic clock, but a long time to wait for season tickets. The meteor hypothesis claims that the earth was shrouded in an enormous dust cloud for 1,000 years, but some of you may have noticed that if you throw something into the air it doesn’t normally take 1,000 years for it to fall back to the ground. Obviously the impact of a large meteor would throw a huge quantity of earth high into the atmosphere, but 1,000 years is a long time, and the assumption here is that gravity was fully functional at the time. So, was it a meteor? Maybe, but then again, maybe it wasn’t. One thing about the meteor hypothesis: it left behind an easily identifiable footprint. Something to sink our teeth into, so to speak. But if it wasn’t a meteor, what was it? There are a number of possibilities:

A sudden pole shift:

Could have altered local climates faster than existing species could adapt.

A freak solar flare:

Could have briefly incinerated the planet.

Evolving mammals:

Their taste for reptile eggs might have pushed the dinosaurs past the tipping point.

Disease:

There have been dozens of pandemics in just the last thousand years. What

might have happened across thousands of millennia?

My book (Full Circle) suggests that the dinosaurs were wiped out in the mother of all pandemics.

Unfortunately for us, the virus survived, frozen in the bones of a long dead beast, buried in the arctic ice.