What defines who we are? Until now, the biological answer has been our genes. Leading biologist Alfonso Martinez Arias breaks with popular tradition to make a bold argument: what defines us is our cells. Drawing on groundbreaking research, he reveals that we are composed of a thrillingly complex, constantly rearranging symphony of cells that know how to count, feel, and give form to our bodies. While DNA is important, nothing in your genes explains why your heart is on the left, why you have five fingers and not ten, why genetically identical twins have different sets of fingerprints, or why it's possible for a mother to apparently share no DNA with the children she gave birth to! At the heart of it all is a powerful new conception of the essence of life. Our identities are shaped by the interconnections between cells, working cooperatively, creating something greater than its parts - the unbroken lineage that connects us to the fertilized egg from which we developed and back through the billions of years of our planet's history, to the very first cell of all life on Earth. A sweeping revision of both the present and the history of life, The Master Builder puts forward a new paradigm for understanding biology, transforming our approach to where we come from, what shapes us, and where we are going - as individuals, a species, and the community of life itself.

How does a single cell develop into myriad different specialised cell types, control the organization of these different cells into tissues and organs, and ultimately form an unimaginably complex living organism such as a human? Furthermore, how is it possible for some adult animals, but not others, to regenerate fully functioning limbs? Principles of Development opens up the fascinating field of developmental biology to those wanting to understand the answers to questions such as these. Cutting edge science is explained clearly and succinctly and is richly illustrated with a variety of custom drawn figures, animations, and links to online movies that show development happening in real time. The emphasis throughout the text is always on the key principles of development - the underlying processes shared by diverse groups of organisms. This focus on principles provides a framework on which a richer understanding of specific topics can be built. Moreover, extensive pedagogical support is provided, both in the book and online, making this text the complete package for those studying developmental biology. Online Resources For students: -Test your understanding with multiple choice questions and answer guidance to long-answer questions from the book -Gain a three dimensional perspective of development by watching the movies of developing model organisms -View the signalling pathway animations to see these complex processes broken down step by step -Expand your knowledge and guide your studies with the suggested web activities - Examine and interpret raw data obtained by Cheryll Tickle and members of her laboratory and presented in silico For registered adopters of the text: -Download the figures from the book to use in lectures and hand-outs -Help your students delve into the research literature with the Journal Club -Download the test bank or import it into your VLE -PowerPoint of In silico practicals to use in class

What defines who we are? For decades, the biological answer has been our genes. In The Master Builder, leading biologist Alfonso Martinez Arias breaks with decades of scientific and popular tradition to make a bold argument: what defines us is our cells. Drawing on new research from his lab and others, Martinez Arias reveals that we are composed of a thrillingly complex, constantly rearranging symphony of cells that know how to count, feel, and ultimately give form to our bodies. While DNA is important, Richard Dawkins's vision of the selfish gene that controls everything is not a good description of how biology actually works. As Martinez Arias shows, nothing in your genes explains why your heart is on the left side of your body, why you have five fingers and not ten, or why genetically identical twins have different sets of fingerprints and why it's possible for a mother to apparently share no DNA with the children to whom she gave birth! At the heart of it all is not simply gee-whiz science, but a powerful new conception of the essence of life. Our identities are shaped not simply by our genes, but by the interconnections between all our cells, working as a sort of symphony-cooperative, and creating something greater than its parts could on their own-and the unbroken lineage of cells that connects us to the first fertilized egg from which we developed-and in turn, back through the billions of years of our planet's history, to the very first cell in the history of all life on Earth. A sweeping revision of both the present and history of life, The Master Builder puts forward a new paradigm for understanding biology, one rooted in cellular cooperation, not selfish genes. Engaging and ambitious, it will transform our understanding of where we come from, what shapes us, and where we are going, as individuals, a species, and the community of life itself.