This series was established to create comprehensive treatises on specialized topics in developmental biology. Such volumes are especially vital in develop­ mental biology, since it is a very diverse field that receives contributions from a wide variety of disciplines. This series is a meeting-ground for the various practitioners of this science, facilitating an integration of heterogeneous infor­ mation on. specific topics. Each volume is intended to provide the conceptual basis for a comprehen­ sive understanding of its topic as well as an analysis of the key experiments upon which that understanding is based. The specialist in any aspect of devel­ opmental biology should understand the experimental background of the field and be able to place that body of information in context to ascertain where additional research would be fruitful. At that point, the creative process takes over, and new experiments are designed. This series is intended to be a vital link in that ongoing process of learning and discovery. If it facilitates schol­ arship, it will serve an important function.

Developmental biology has been transformed recently by discoveries in the fields of molecular biology, cell biology, and immunology. New ways of manip­ ulating mammalian development are uncovering control mechanisms and ena­ bling us to apply them in solving practical problems in animal production and human health. This book outlines some of these new manipulations and how they have contributed to the present state of developmental biology. Chapter 1 describes gene transfer by micro injection of cloned recombinant DNA into zygotes. Although the factors that affect transformation frequencies and integration sites are still unknown, such techniques offer a number of exciting prospects. Research models for human disease coula be artificially created and desirable characteristics in agricultural animals could be - hanced. . The theme of cell-to-cell transfer is continued in Chapters 2 and 3. Chapter 2 describes pronuclear transplantation by Sendai virus-induced fusion of the karyoplast with the enucleated embryo. Using this procedure, it has been dem­ onstrated that both male and female genomes are essential for normal develop­ ment, although the reason for this is not yet understood. Chapter 3 describes studies on the fusion of whole oocytes. .

This book launches a new continuing series in developmental biology. Any new publishing venture in science can only be justified if it satisfies a need and fulfills that need in an exemplary way. I believe that there is an acute need for comprehensive treatises on specialized topics in developmental biology-especially because this is a very diverse field that receives con­ tributions from a wide variety of disciplines. It is difficult to remain abreast of progress in multifaceted topics and to understand how the various aspects of a topic interrelate. The volumes that will comprise this series are designed to facilitate those processes. Each volume of this series will attempt to convey the current status of research and thought on a specific topic in development, place current research within historical perspective, and lay the intellectual groundwork for future research. These volumes are intended to provide an in-depth background on these topics for advanced undergraduates, graduate stu­ dents, and senior scientists. An investigator considering research in one of these areas will get an overview of the field as well as discover the status of recent research in the area.

This series was established to create comprehensive treatises on specific topics in developmental biology. Such volumes serve a useful role in developmental biology, which is a very diverse field that receives contributions from a wide variety of disciplines. This series is a meeting ground for the various practi­ tioners of this science, facilitating an integration of heterogeneous information on specific topics. Each volume is comprised of chapters selected to provide the conceptual basis for a comprehensive understanding of its topic as well as an analysis of the key experiments upon which that understanding is based. The specialist in any aspect of developmental biology should understand the experimental back­ ground of the specialty and be able to place that body of information in context, in order to ascertain where additional research would be fruitful. The creative process then generates new experiments. This series is intended to be a vital link in that ongoing process of learning and discovery.

I am pleased to include this book as Volume 6 of Developmental Biology: A Comprehensive Synthesis. It has been edited by two of the foremost investiga­ tors in the study of genomic adaptability. lowe a special debt of gratitude to Dr. Marie A. DiBerardino, who developed the concept of the volume. Dr. DiBerar­ dino is also a very active member of the editorial board for this series. Much of the success of this series is due to her valuable advice. This series was established to create comprehensive treatises on specific topics in developmental biology. Such volumes serve a useful role in develop­ mental biology, since it is a very diverse field that receives contributions from a wide variety of disciplines. This series is a meeting ground for the various practitioners of this science, facilitating an integration of heterogeneous infor­ mation on specific topics. Each volume is intended to provide the conceptual basis for a comprehen­ sive understanding of its topic as well as analysis of the key experiments upon which that understanding is based. The specialist in any aspect of developmen­ tal biology should understand the experimental background of the field and be able to place that body of information in context to ascertain where additional research would be fruitful. At that point, the creative process generates new experiments. This series is intended to be a vital link in that process of learning and discovery.

"Glory to the science of embryology!" So Johannes Holtfreter closed his letter to this editor when he granted permission to publish his article in this volume. And glory there is: glory in the phenomenon of animals developing their complex morphologies from fertilized eggs, and glory in the efforts of a relatively small group of scientists to understand these wonderful events. Embryology is unique among the biological disciplines, for it denies the hegemony of the adult and sees value (indeed, more value) in the stages that lead up to the fully developed organism. It seeks the origin, and not merely the maintenance, of the body. And if embryology is the study of the embryo as seen over time, the history of embryology is a second-order derivative, seeing how the study of embryos changes over time. As Jane Oppenheimer pointed out, "Sci­ ence, like life itself, indeed like history, itself, is a historical phenomenon. It can build itself only out of its past. " Thus, there are several ways in which embryology and the history of embryology are similar. Each takes a current stage of a developing entity and seeks to explain the paths that brought it to its present condition. Indeed, embryology used to be called Entwicklungsgeschichte, the developmental history of the organism. Both embryology and its history interpret the interplay between internal factors and external agents in the causation of new processes and events.

This series was established to create comprehensive treatises on specialized topics in developmental biology. Such volumes are especially vital in develop­ mental biology, since it is a very diverse field that receives contributions from a wide variety of disciplines. This series is a meeting-ground for the various practitioners of this science, facilitating an integration of heterogeneous infor­ mation on. specific topics. Each volume is intended to provide the conceptual basis for a comprehen­ sive understanding of its topic as well as an analysis of the key experiments upon which that understanding is based. The specialist in any aspect of devel­ opmental biology should understand the experimental background of the field and be able to place that body of information in context to ascertain where additional research would be fruitful. At that point, the creative process takes over, and new experiments are designed. This series is intended to be a vital link in that ongoing process of learning and discovery. If it facilitates schol­ arship, it will serve an important function.

Developmental biology has been transformed recently by discoveries in the fields of molecular biology, cell biology, and immunology. New ways of manip­ ulating mammalian development are uncovering control mechanisms and ena­ bling us to apply them in solving practical problems in animal production and human health. This book outlines some of these new manipulations and how they have contributed to the present state of developmental biology. Chapter 1 describes gene transfer by micro injection of cloned recombinant DNA into zygotes. Although the factors that affect transformation frequencies and integration sites are still unknown, such techniques offer a number of exciting prospects. Research models for human disease coula be artificially created and desirable characteristics in agricultural animals could be - hanced. . The theme of cell-to-cell transfer is continued in Chapters 2 and 3. Chapter 2 describes pronuclear transplantation by Sendai virus-induced fusion of the karyoplast with the enucleated embryo. Using this procedure, it has been dem­ onstrated that both male and female genomes are essential for normal develop­ ment, although the reason for this is not yet understood. Chapter 3 describes studies on the fusion of whole oocytes. .

This book launches a new continuing series in developmental biology. Any new publishing venture in science can only be justified if it satisfies a need and fulfills that need in an exemplary way. I believe that there is an acute need for comprehensive treatises on specialized topics in developmental biology-especially because this is a very diverse field that receives con­ tributions from a wide variety of disciplines. It is difficult to remain abreast of progress in multifaceted topics and to understand how the various aspects of a topic interrelate. The volumes that will comprise this series are designed to facilitate those processes. Each volume of this series will attempt to convey the current status of research and thought on a specific topic in development, place current research within historical perspective, and lay the intellectual groundwork for future research. These volumes are intended to provide an in-depth background on these topics for advanced undergraduates, graduate stu­ dents, and senior scientists. An investigator considering research in one of these areas will get an overview of the field as well as discover the status of recent research in the area.

This series was established to create comprehensive treatises on specific topics in developmental biology. Such volumes serve a useful role in developmental biology, which is a very diverse field that receives contributions from a wide variety of disciplines. This series is a meeting ground for the various practi­ tioners of this science, facilitating an integration of heterogeneous information on specific topics. Each volume is comprised of chapters selected to provide the conceptual basis for a comprehensive understanding of its topic as well as an analysis of the key experiments upon which that understanding is based. The specialist in any aspect of developmental biology should understand the experimental back­ ground of the specialty and be able to place that body of information in context, in order to ascertain where additional research would be fruitful. The creative process then generates new experiments. This series is intended to be a vital link in that ongoing process of learning and discovery.

I am pleased to include this book as Volume 6 of Developmental Biology: A Comprehensive Synthesis. It has been edited by two of the foremost investiga­ tors in the study of genomic adaptability. lowe a special debt of gratitude to Dr. Marie A. DiBerardino, who developed the concept of the volume. Dr. DiBerar­ dino is also a very active member of the editorial board for this series. Much of the success of this series is due to her valuable advice. This series was established to create comprehensive treatises on specific topics in developmental biology. Such volumes serve a useful role in develop­ mental biology, since it is a very diverse field that receives contributions from a wide variety of disciplines. This series is a meeting ground for the various practitioners of this science, facilitating an integration of heterogeneous infor­ mation on specific topics. Each volume is intended to provide the conceptual basis for a comprehen­ sive understanding of its topic as well as analysis of the key experiments upon which that understanding is based. The specialist in any aspect of developmen­ tal biology should understand the experimental background of the field and be able to place that body of information in context to ascertain where additional research would be fruitful. At that point, the creative process generates new experiments. This series is intended to be a vital link in that process of learning and discovery.

"Glory to the science of embryology!" So Johannes Holtfreter closed his letter to this editor when he granted permission to publish his article in this volume. And glory there is: glory in the phenomenon of animals developing their complex morphologies from fertilized eggs, and glory in the efforts of a relatively small group of scientists to understand these wonderful events. Embryology is unique among the biological disciplines, for it denies the hegemony of the adult and sees value (indeed, more value) in the stages that lead up to the fully developed organism. It seeks the origin, and not merely the maintenance, of the body. And if embryology is the study of the embryo as seen over time, the history of embryology is a second-order derivative, seeing how the study of embryos changes over time. As Jane Oppenheimer pointed out, "Sci­ ence, like life itself, indeed like history, itself, is a historical phenomenon. It can build itself only out of its past. " Thus, there are several ways in which embryology and the history of embryology are similar. Each takes a current stage of a developing entity and seeks to explain the paths that brought it to its present condition. Indeed, embryology used to be called Entwicklungsgeschichte, the developmental history of the organism. Both embryology and its history interpret the interplay between internal factors and external agents in the causation of new processes and events.