Life began three and a half billion years ago, necessarily about as simple as it could be, because life arose spontaneously from the organic compounds in the primeval oceans.

It seems the height of antiquated hubris to claim that the universe carried on as it did for billions of years in order to form a comfortable abode for us. Chance and historical contingency give the world of life most of its glory and fascination. I sit here happy to be alive and sure that some reason must exist for "why me?" Or the earth might have been totally covered with water, and an octopus might now be telling its children why the eight-legged God of all things had made such a perfect world for cephalopods.

Our creationist detractors charge that evolution is an unproved and unprovable charade — a secular religion masquerading as science. They claim, above all, that evolution generates no predictions, never exposes itself to test, and therefore stands as dogma rather than disprovable science. This claim is nonsense.

I am glad that the life of pandas is so dull by human standards, for our efforts at conservation have little moral value if we preserve creatures only as human ornaments; I shall be impressed when we show solicitude for warty toads and slithering worms.

People may believe correct things for the damndest and weirdest of wrong reasons.

The pathways that have led to our evolution are quirky, improbable, unrepeatable and utterly unpredictable.

Any decent writer writes because there's some deep internal need to keep learning.