Mass extinctions may not threaten distant futures, but they are decidedly unpleasant for species caught up in the throes of their power.

I was lucky to wander into evolutionary theory, one of the most exciting and important of all scientific fields. I had never heard of it when I started at a rather tender age; I was simply awed by dinosaurs. I thought paleontologists spent their lives digging up bones and putting them together, never venturing beyond the momentous issue of what connects to what. Then I discovered evolutionary theory. Ever since then, the duality of natural history-richness in particularities and potential union in underlying explanation-has propelled me.

It is the things we think we know - because they are so elementary or because they surround us - that often present the greatest difficulties when we are actually challenged to explain them.

No rational order of divine intelligence unites species. The natural ties are genealogical along contingent pathways of history.

Theory-free science makes about as much sense as value-free politics.

We are the offspring of history, and must establish our own paths in this most diverse and interesting of conceivable universes—one indifferent to our suffering, and therefore offering us maximum freedom to thrive, or to fail, in our own chosen way.

The origin of Homo sapiens, as a tiny twig on an improbable branch of a contingent limb on a fortunate tree, lies well below the boundary.