Eating the Sun, by Oliver Morton

As religions go, sun worship makes the most sense. Our local stellar furnace supplies a constant stream of radiation. Daytime sees every square inch of the Earth bombarded with free energy. Want a planet with winds, ocean currents and abundant life? Let there be light.

The key exploiters of this solar largesse are plants. Every leaf is poised to catch its share and use it to build complexity. While busy humans forage or hunt (or drive to Tesco), plants just sit there. Give them air, water and light, and they can do the rest.

We learn this in school, of course. But we learn astonishingly little about how plants pull off this amazing trick. Inside the leaf is a finely honed set of molecular machines. They work in a cunningly wrought chain that allows the Sun's energy to power molecular building works 93 million miles away from where it was generated.

This whole apparatus for photosynthesis, which Oliver Morton details in the first third of this fine book, is – his word – magnificent. It is now understood at a level that also astonishes. The complex of proteins that orchestrate the whole affair has been dissected more or less atom by atom: one of the great scientific triumphs of the past century.

After chronicling these discoveries and their makers, the book zooms out to relate the role of photosynthesis in shaping the living Earth over three billion years. Molecules still matter, but this is also a story of larger events, seen from a Gaian perspective, which views life, atmosphere, oceans, rocks and soil as a vast, interactive system. Finally, another shift in focus highlights the last 200 years, and the human impact.

What begins as an essay on an under-appreciated part of the history of science turns into something richer and more ruminative. The result has everything you could possibly want from a popular science book. There is wonder here, and intellectual excitement; clear explanation and lyrical writing; and much new insight into how the world works, linking the very small and very large.

It even finishes with an unfashionably optimistic take on global warming. Now that we understand the natural nanomachinery that captures solar energy, Morton reckons, it is only a matter of time before we can redesign it to generate fuel – subtly engineered, like leaves, to recycle carbon. Research funders should feel a duty to take heed. Everyone else can read Morton's fascinating book for pleasure.

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