Evolution of the Structure and Function of the Notochord

Although it is the defining organ of the Chordata, the notochord and its cells are one of the least understood vertebrate organs. This may be because large parts of the notochord are often replaced with cartilaginous or bony vertebral bodies. The presence of cartilage in the notochord raises questions about the evolutionary relationships between notochord cells and cartilage cells. This book integrates classical analytical studies with recent palaeontological, experimental, and molecular studies in both developmental and evolutionary contexts. For example, although the early signaling function of the notochord is conserved across the vertebrates, many will be surprised to find that the role of the notochord in vertebral body development in tetrapods is not the blueprint for all vertebrates. Recent studies on zebrafish and medaka embryos have uncovered the molecular mechanisms of a somite-independent notochord-driven segmentation process that establishes vertebral centra and intervertebral spaces. As this process is not restricted to teleosts, the authors have written a general discussion about the role of the notochord in vertebral formation. Modularity and segmentation of the vertebral column are related topics. Further overarching themes are the structure, function and fate of the notochord in adult vertebrates and notochord-cartilage relationships.

Key Features

• The first book devoted to notochord development, function and evolution
• Includes and integrates information on the notochord from studies going back 169 years
• Integrates developmental, molecular, functional, experimental and palaeontological studies
• Documents the fate of the notochord across the vertebrates
• Extensively illustrated with classical and new images

Related Titles

Bard, J. Evolution: The Origins and Mechanisms of Diversity (ISNB 978-0-3673-5701-6)

Leys, S. and Hejnol. A. Origin and Evolution of Metazoan Cell Types (ISBN 978-1-1380-3269-9)

Paul Eckhard Witten is Assistant Professor in the Departmenbt of Biology at Ghent University in Brussels. His research focuses on development, plasticity, and remodeling of skeletal tissues; in particular bone, cartilage and teeth of teleost fish. Processes are analyzed in a comparative developmental and evolutionary context. Brian Keith Hall FRSC (born, 1941) is the George S. Campbell Professor of Biology and University Research Professor Emeritus at Dalhousie University in Halifax, Nova Scotia. Professor Hall has researched and extensively written on bone and cartilage formation in developing vertebrate embryos. He is an active participant in the evolutionary developmental biology (EVO-DEVO) debate on the nature and mechanisms of animal body plan formation. Professor Hall has proposed that the neural crest tissue of vertebrates may be viewed as a fourth embryonic germ layer. As such, the neural crest - in Hall’s view - plays a role equivalent to that of the endoderm, mesoderm, and ectoderm of bilaterian development and is a definitive feature of vertebrates (as hypothesized by Gans and Northcutt[1983]). As such, vertebrates are the only quadroblastic, rather than triploblastic bilaterian animals. In vertebrates the neural crest serves to integrate the somatic division (derived from ectoderm and mesoderm) and visceral division (derived from endoderm and mesoderm) together via a wide range novel vertebrate tissues (bone, cartilage, sympathetic nervous system, etc...). He has been associated with Dalhousie University since 1968. Since his retirement in 2007, he has been University Research Professor Emeritus and Emeritus Professor of Biology. (this taken from https: //en.wikipedia.org/wiki/Brian_K._Hall ).