Not a microbial biologist, I approached this book with a bit of trepidation, imagining lengthy discussions of biochemistry. Instead, I was immediately engaged by Falkowski's conversational, fluid writing (“Let us take a look ‘under the hood’ to see how some of the machinery that makes these invisible creatures work”; p. 46), personal anecdotes (“It took me a few years to understand how this transition in the chemistry of the Black Sea…”; p. 83), and interesting choice of topics. The author easily distills volumes of relevant history down to the salient points to set the scene for the biology he relates. As such, the book is focused as much on the history of science, including the processes of invention of various scientific tools as well as famous people, as it is on advocacy of the long-needed recognition of the importance of microbes in our world. For instance, the story of evolution as it emerged in the 19th century, of Darwin's trajectory of thoughts on evolution by natural selection, is composed of only 10 pages, yet I didn't feel that any of the information that was important to Falkowski's story was missing. The author steps through some of this history to demonstrate his claim that “Microbes were missed because of our observational biases…[and yet] they played an outsized role in making this planet function” (p. 22). He effectively shows the progress that has been made in the field. He also highlights many of the unknowns – the still-to-be-done work, including current unsolved controversies within science.

By Chapter 4, the biochemistry comes in, with clear but not overly simplified diagrams, and Falkowski's writing remains understandable. Describing the formation of ATP, he explains, “As the shaft physically turns, it mechanically moves the larger proteins (the deck of the merry-go-round) which bind ADP and phosphate” (p. 59). Discussions of rising oxygen levels in the early atmosphere, RuBisCO, horizontal gene transmission, symbiosis and microbial communities, evolution of multicellularity, opsins, petroleum, the Haber-Bosch reaction, synthetic biology, and extraterrestrial explorations make you feel as if your biology courses are coming alive in a conversation with a master storyteller. Each chapter ends with a logical transition that leads to the next large topic, so you feel as if the entire book is one continuous, interwoven concept. At the end are a few extra readings suggested for each chapter and an extensive index. “In sum, the oversight of microbes, in both the literal and figurative senses, distorted our worldview of evolution for more than a century, and including microbes in our understanding of evolution is still a work in progress” (p. 12). Life's Engines, easily accessible to the lay reader but engaging for the scientist as well, will go a long way to boost that work in progress.