As a biology teacher and an evolution educator, I needed this book. For those of us who teach in the K–12 universe, our understanding and consequently our teaching of evolution can tend to be slow to evolve as the resources we use to teach evolutionary concepts are themselves slow to embrace new advances in the field. In the world of teaching introductory evolution, a comprehensive view of evolutionary thinking is likely to include an overview of classic Darwinism followed by a connection to the Modern Synthesis and a mention of modern DNA sequencing as it lends support to ideas of species’ common ancestry as part of the tree of life.

In Tangled Tree, David Quammen tells the next chapter in the development of evolutionary theory as he relates the groundbreaking work of Carl Woese and a wealth of other microbiologists. Woese is best known for his work describing and placing the Archaea into the updated three-domain, six-kingdom system of taxonomy, but he remains largely unknown to the vast majority of biology students. This deeply researched and richly written book seeks to change that and make sure that readers never forget this seemingly overlooked biologist from Urbana, Illinois.

Quammen gives his readers valuable background about the early days of evolutionary theory and the development of the “tree of life” metaphor. He provides us with strong historical descriptions of how “tree thinking” came to dominate evolutionary thought, which sets the stage for Woese and colleagues’ discoveries that in addition to the verticality of nuclear gene transfer from generation to generation, there is also a mechanism that allows genes to move horizontally between species. This horizontal gene transfer serves to modify the metaphorical tree into more of a web, with both vertical and horizontal phylogenies for many species. This conceptual revolution gives Tangled Tree its name.

In addition to its detailed presentation of the science behind horizontal gene transfer and a new phylogenetic view of the tree of life, Tangled Tree illustrates the ways in which modern biology now works. Quammen's storytelling does a stellar job of showing us that current research is more than mundane lab work. He details the relationships and inspirations not only of Woese, but of his extended community of collaborators and colleagues who encouraged and challenged each other to expand our understanding of this new field of evolutionary thought. Indeed, this book is a great reminder that science, as a way of knowing, is influenced greatly by the human strengths and weaknesses of those doing the science.

All of us who teach evolution in our classes would do well to read Tangled Tree so that we update and deepen our understanding of both the history of evolutionary thought and the diversity of all current life on Earth. This is a fine work that addresses both the natural and the history in natural history.

AMANDA L. GLAZE is an Assistant Professor of Middle Grades & Secondary Science Education at Georgia Southern University in Statesboro, Georgia. In addition to science teacher education, she has taught courses in biological sciences for grades 7–12 and undergraduate students over the last ten years. Her interests include evolutionary biology, science and religion, and the intersections of science and society – specifically where scientific understandings are deemed controversial by the public. Glaze holds degrees in science education from The University of Alabama and Jacksonville State University. Her address is Department of Teaching & Learning, Georgia Southern University, PO BOX 8134, Statesboro, GA 30458; email: