Book excerpt: Evolutionary developmental biology, or 'evo-devo', is the study of the relationship between evolution and development. Dealing specifically with the generative mechanisms of organismal form, evo-devo goes straight to the core of the developmental origin of variation, the raw material on which natural selection (and random drift) can work. Evolving Pathways brings together contributions that represent a diversity of approaches. Topics range from developmental genetics to comparative morphology of animals and plants alike, and also include botany and palaeontology, two disciplines for which the potential to be examined from an evo-devo perspective has largely been ignored until now. Researchers and graduate students will find this book a valuable overview of current research as we begin to fill a major gap in our perception of evolutionary change.