Most of the cranial sense organs of vertebrates arise from embryonic structures known as cranial placodes. Such placodes also give rise to sensory neurons that transmit information to the brain as well as to many neurosecretory cells. This book focuses on the development of sensory and neurosecretory cell types from cranial placodes by introducing the vertebrate head with its sense organs and neurosecretory organs and providing an overview of the various cranial placodes and their derivatives, including evidence of common embryonic primordia. Schlosser discusses how these primordia are established in the early embryo and how individual placodes develop. The latter chapters explain how various placodally derived sensory and neurosecretory cell types differentiate into discrete structures.

Most of the cranial sense organs of vertebrates arise from embryonic structures known as cranial placodes. Such placodes also give rise to sensory neurons that transmit information to the brain as well as to many neurosecretory cells. This book focuses on the development of sensory and neurosecretory cell types from cranial placodes by introducing the vertebrate head with its sense organs and neurosecretory organs and providing an overview of the various cranial placodes and their derivatives, including evidence of common embryonic primordia. Schlosser discusses how these primordia are established in the early embryo and how individual placodes develop. The latter chapters explain how various placodally derived sensory and neurosecretory cell types differentiate into discrete structures.

Most vertebrate cranial sense organs arise from placodes. These placodes give rise to sensory neurons that transmit information to the brain and neurosecretory cells. This book reviews the evolutionary origin of the sensory and neurosecretory cell types. It summarizes our current understanding of vertebrate evolution, clarifies conceptual issues relating to homology and evolutionary innovation of cell types, compares the sensory and neurosecretory cell types with similar cell types in other animals, and addresses the question of how cranial placodes evolved as novel structures in vertebrates by redeploying pre-existing and sometimes evolutionarily ancient cell types.

Most of the cranial sense organs of vertebrates arise from embryonic structures known as cranial placodes. Such placodes also give rise to sensory neurons that transmit information to the brain as well as to many neurosecretory cells. This book focuses on the development of sensory and neurosecretory cell types from cranial placodes by introducing the vertebrate head with its sense organs and neurosecretory organs and providing an overview of the various cranial placodes and their derivatives, including evidence of common embryonic primordia. Schlosser discusses how these primordia are established in the early embryo and how individual placodes develop. The latter chapters explain how various placodally derived sensory and neurosecretory cell types differentiate into discrete structures.

Der erste Teil dieses Buches zeichnet die wissenschaftstheoretischen Auseinandersetzungen um den Reduktionismus ausgehend von den Positionen des Wiener Kreises bis heute nach, wobei sich das reduktionistische Programm als undurchfuhrbar erweist. Wie kann aber der Einheit der Welt Rechnung getragen werden, wenn eine Fulle von Disziplinen scheinbar beziehungslos nebeneinanderstehen? Diese Frage versucht der zweite Teil mit der Grundlegung einer Allgemeinen Systemtheorie zu beantworten. Mit der Einfuhrung eines allgemeinen Systembegriffs konnen Brucken zwischen den Disziplinen geschlagen werden, ohne die Existenzberechtigung verschiedener Disziplinen in Frage zu stellen."

"Modularity in Development and Evolution" offers the first sustained exploration of modules from developmental and evolutionary perspectives. Contributors discuss what modularity is, how it can be identified and modeled, how it originated and evolved, and its biological significance. Covering modules at levels ranging from genes to colonies, the book focuses on their roles not just in structures but also in processes such as gene regulation. Among many exciting findings, the contributors demonstrate how modules can highlight key constraints on evolutionary processes.
A timely synthesis of a crucial topic, "Modularity in Development and Evolution" shows the invaluable insights modules can give into both developmental complexities and their evolutionary origins.