If we are still here to witness the destruction of our planet some five billion years or more hence, then we will have achieved something so unprecedented in the history of life that we should be willing to sing our swansong with joy - Sic Transit Gloria Mundi.

World views are social constructions and they channel the search for facts. But facts are found and knowledge progresses, however fitfully.

Organisms are not billiard balls, propelled by simple and measurable external forces to predictable new positions on life's pool table. Sufficiently complex systems have greater richness. Organisms have a history that constrains their future in myriad, subtle ways.

All evolutionary biologists know that variation itself is nature's only irreducible essence... I had to place myself amidst the variation.

The history of life is more adequately represented by a picture of 'punctuated equilibria' than by the notion of phyletic gradualism. The history of evolution is not one of stately unfolding, but a story of homeostatic equilibria, disturbed only 'rarely' (i.e. rather often in the fullness of time) by rapid and episodic events of speciation.

People talk about human intelligence as the greatest adaptation in the history of the planet. It is an amazing and marvelous thing, but in evolutionary terms, it is as likely to do us in as to help us along.

In science, 'fact' can only mean 'confirmed to such a degree that it would be perverse to withhold provisional assent.' I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms.