Thinking of the history of life on Earth in terms of "energy epochs"

Olivia P. Judson's paper in Nature, The energy expansions of evolution, presents a novel, beautifully written and presented frame for looking at the history of life on Earth: as a series of five epochs in which energy became more abundant and available to lifeforms, allowing them to scale up in complexity and fecundity: geochemical energy, sunlight, oxygen, flesh and fire. (more")