Abstract
What would a Grand Unified Theory of big-scale evolution look like? Here is one answer. It would unify the various trends that have been documented and suspected, the features of life that have been said to increase over its history—body size, fitness, intelligence, versatility, evolvability, energy intensiveness, energy rate density, and complexity-in-the-sense-of-part-types, and complexity-in-the-sense-of-hierarchy. It would show us how these putative trends are related to each other, how they are all the product of some single simple principle or some small set of principles. It would identify and connect all of the variables that are expected to increase over the long haul in evolution, perhaps in a single equation, or if not yet quantifiable, perhaps in a single breath.The obvious unifying candidate is fitness. Natural selection acts to adapt organisms to local circumstances, of course, but it might also act over the long term to produce adaptation on a bigger scale, to produce or ..