The Embryo Project Encyclopedia (https://embryo.asu.edu) is an open-access digital encyclopedia devoted to recording and contextualizing the science of embryos, development, and reproduction. The collection of documents, images, and multimedia housed here serves as the Encyclopedia's permanent archive.

Jane Maienschein, ASU University Professor, Regents Professor, and Director of the Biology and Society Program, started the Embryo Project Encyclopedia in 2007 with support from the National Science Foundation.

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Mechanism of Notch Signaling: The image depicts a type of cell signaling, in which two animal cells interact and transmit a molecular signal from one to the other. The process results in the production of proteins, which influence the cells as they differentiate, move, and contribute to embryological development. In

Mechanism of Notch Signaling: The image depicts a type of cell signaling, in which two animal cells interact and transmit a molecular signal from one to the other. The process results in the production of proteins, which influence the cells as they differentiate, move, and contribute to embryological development. In the membrane of the signaling cell, there is a ligand (represented by a green oval). The ligand functions to activate a change in a receptor molecule. In the receiving cell, there are receptors; in this case, Notch proteins (represented by orange forks). The Notch proteins are embedded in the receiving cell membrane, and they have at least two parts: an intracellular domain (inside the cell) and the receptor (outside the cell). Once the ligand and receptor bind to each other, a protease (represented by the dark red triangle) can sever the intracellular domain from the rest of the Notch receptor. Inside the nucleus of the receiving cell (represented by the gray area) are the cellês DNA (represented by the multi-colored helices) and its transcription factors (blue rectangles). Transcription factors are proteins that bind to DNA to regulate transcription, the first step in gene expression, which eventually yields proteins or other products. Initially, repressor proteins (represented by a red irregular hexagon) prevent transcription factors from allowing transcription. When the severed Notch receptor intracellular domain reaches the nucleus, it displaces the repressor. The transcription factor can then signal for transcription to occur. 1) There is a Notch receptor protein in the membrane of a receiving cell, and a ligand for this receptor (for example, Delta) in the membrane of the signaling cell. When the ligand binds to the receptor, the intracellular domain of the receptor changes shape. 2) Inside the receiving cell, there are proteases. Once the intracellular domain of the receptor changes shape, the protease can bind to it and shear the intracellular domain away from the rest of the receptor molecule. 3) The severed intracellular domain is shuttled to the receiving cell nucleus. Here, the intracellular domain displaces a repressor protein. This allows a transcription factor to initiate DNA transcription. During transcription, DNA is used as a template to create RNA. Following transcription, the process of translation occurs, which uses RNA as a template to create proteins. These proteins influence the behavior, fate, and differentiation of cells, which contribute to normal embryonic development

Created2014-08-21
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Stephen Jay Gould studied snail fossils and worked at Harvard University in Cambridge, Massachusetts during the latter half of the twentieth century. He contributed to philosophical, historical, and scientific ideas in paleontology, evolutionary theory, and developmental biology. Gould, with Niles Eldredge, proposed the theory of punctuated equilibrium, a view of

Stephen Jay Gould studied snail fossils and worked at Harvard University in Cambridge, Massachusetts during the latter half of the twentieth century. He contributed to philosophical, historical, and scientific ideas in paleontology, evolutionary theory, and developmental biology. Gould, with Niles Eldredge, proposed the theory of punctuated equilibrium, a view of evolution by which species undergo long periods of stasis followed by rapid changes over relatively short periods instead of continually accumulating slow changes over millions of years. In his 1977 book, Ontogeny and Phylogeny, Gould reconstructed a history of developmental biology and stressed the importance of development to evolutionary biology. In a 1979 paper coauthored with Richard Lewontin, Gould and Lewonitn criticized many evolutionary bioligists for relying solely on adaptive evolution as an explanation for morphological change, and for failing to consider other explanations, such as developmental constraints.

Created2014-02-18
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Aristotle studied developing organisms, among other things, in ancient Greece, and his writings shaped Western philosophy and natural science for greater than two thousand years. He spent much of his life in Greece and studied with Plato at Plato's Academy in Athens, where he later established his own school called

Aristotle studied developing organisms, among other things, in ancient Greece, and his writings shaped Western philosophy and natural science for greater than two thousand years. He spent much of his life in Greece and studied with Plato at Plato's Academy in Athens, where he later established his own school called the Lyceum. Aristotle wrote greater than 150 treatises on subjects ranging from aesthetics, politics, ethics, and natural philosophy, which include physics and biology. Less than fifty of Aristotle's treatises persisted into the twenty-first century. In natural philosophy, later called natural science, Aristotle established methods for investigation and reasoning and provided a theory on how embryos generate and develop. He originated the theory that an organism develops gradually from undifferentiated material, later called epigenesis.

Created2016-07-07
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David Starr Jordan studied fish and promoted eugenics in the US during the late nineteenth and early twentieth centuries. In his work, he embraced Charles Darwin s theory of evolution and described the importance of embryology in tracing phylogenic relationships. In 1891, he became the president of Stanford University in

David Starr Jordan studied fish and promoted eugenics in the US during the late nineteenth and early twentieth centuries. In his work, he embraced Charles Darwin s theory of evolution and described the importance of embryology in tracing phylogenic relationships. In 1891, he became the president of Stanford University in Stanford, California. Jordan condemned war and promoted conservationist causes for the California wilderness, and he advocated for the eugenic sterilization of thousands of Americans. Like many American eugenicists of the early twentieth century, Jordan combined ideas of Mendelian genetics and of Darwinian natural selection to form a basis for limiting or encouraging reproduction in certain individuals and groups based on their perceived hereditary fitness. Like other eugenicists, Jordan s attempt to control the reproductive fate of entire populations marked an episode in the history of reproduction and biology in which its concepts increasingly influenced the social and cultural contexts.

Created2013-06-26
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In 1928 Ezra Seymour Gosney founded the non-profit Human Betterment Foundation (HBF) in Pasadena, California to support the research and publication of the personal and social effects of eugenic sterilizations carried out in California. Led by director Gosney and secretary Paul Popenoe, the HBF collected data on thousands of individuals

In 1928 Ezra Seymour Gosney founded the non-profit Human Betterment Foundation (HBF) in Pasadena, California to support the research and publication of the personal and social effects of eugenic sterilizations carried out in California. Led by director Gosney and secretary Paul Popenoe, the HBF collected data on thousands of individuals in California who had been involuntarily sterilized under a California state law enacted in 1909. The Foundation's assets were liquidated following Gosney's death in 1942. In 1943, Gosney's daughter donated the remaining assets to the California Institute of Technology (Caltech) in Pasadena, California to establish the Gosney research fund for biological research. Between 1928 and 1942, the HBF published extensively on what they believed to be the benefits of sterilization to both patient and society. The HBF and its members existed within the larger context of the American eugenics movement and scientific institutions, including the Eugenics Record Office at Cold Spring Harbor Laboratory in Cold Spring Harbor, New York, which bolstered the movement's goals of the control of human reproduction and human heredity. Moreover, the model sterilization legislation written by the HBF was disseminated throughout the world to eugenics enthusiasts eager to pass laws limiting the reproduction of people they considered to be unfit.

Created2013-07-10
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Georges Cuvier, baptized Georges Jean-Leopold Nicolas-Frederic Cuvier, was a professor of anatomy at the National Museum of Natural History in Paris, France, through the late eighteenth and early nineteenth centuries. Scholars recognize Cuvier as a founder of modern comparative anatomy, and as an important contributor to vertebrate paleontology and geology.

Georges Cuvier, baptized Georges Jean-Leopold Nicolas-Frederic Cuvier, was a professor of anatomy at the National Museum of Natural History in Paris, France, through the late eighteenth and early nineteenth centuries. Scholars recognize Cuvier as a founder of modern comparative anatomy, and as an important contributor to vertebrate paleontology and geology. Cuvier studied the form and function of animal anatomy, writing four volumes on quadruped fossils and co-writing eleven volumes on the natural history of fish with Achille Valenciennes. Moreover, Cuvier constructed a system of classification based on specific and well-articulated principles to help anatomists classify animal taxa. Cuvier had public debate in 1830 with Etienne Geoffroy Saint-Hilaire, a dispute centered on whether form or function matters most for the study of anatomy and whether the transmutation of organic forms can occur over time. Cuvier's opinions influenced the development of biology in France, and his arguments against transmutation of types influenced the reception of Charles Darwin's theory of evolution by natural selection among many French naturalists.

Created2013-07-10
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'On the Permanent Life of Tissues outside of the Organism' reports Alexis Carrel's 1912 experiments on the maintenance of tissue in culture media. At the time, Carrel was a French surgeon and biologist working at the Rockefeller Institute in New York City. In his paper, Carrel reported that he

'On the Permanent Life of Tissues outside of the Organism' reports Alexis Carrel's 1912 experiments on the maintenance of tissue in culture media. At the time, Carrel was a French surgeon and biologist working at the Rockefeller Institute in New York City. In his paper, Carrel reported that he had successfully maintained tissue cultures, which derived from connective tissues of developing chicks and other tissue sources, by serially culturing them. Among all the tissue cultures Carrel reported, one was maintained for more than two months, whereas previous efforts had only been able to keep tissues in vitro for three to fifteen days. Carrel’s experiments contributed to the development of long-term tissue culture techniques, which were useful in the study of embryology and eventually became instrumental in stem cell research. Despite later evidence to the contrary, Carrel believed that as long as the tissue culture method was accurately applied, tissues kept outside of the organisms should be able to divide indefinitely and have permanent life.

Created2012-05-06
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Etienne Geoffroy Saint-Hilaire, commonly known as Geoffroy, studied animals, their anatomy and their embryos, and teratogens at the National Museum of Natural History in Paris, France in the eighteenth and nineteenth centuries. Geoffroy also helped develop several specialized fields in the life sciences, including experimental embryology. In his efforts to

Etienne Geoffroy Saint-Hilaire, commonly known as Geoffroy, studied animals, their anatomy and their embryos, and teratogens at the National Museum of Natural History in Paris, France in the eighteenth and nineteenth centuries. Geoffroy also helped develop several specialized fields in the life sciences, including experimental embryology. In his efforts to experimentally demonstrate the theory of recapitulation, Geoffroy developed techniques to intervene in the growth of embryos to see whether they would develop into different kinds of organisms. Moreover, Geoffroy emphasized the concept of l'unite de composition (the unity of plan). Geoffroy disputed in 1830 with Georges Cuvier over whether form or function matters most for the study of anatomy and whether the transformation of organic forms can occur over time. Geoffroy's conceptual contributions, as well as his experimental research, influenced embryological research on animal morphology and teratogens, and later the field of evolutionary paleontology.

Created2013-08-05
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Christiane Nusslein-Volhard studied how genes control embryonic development in flies and in fish in Europe during the twentieth and twenty-first centuries. In the 1970s, Nusslein-Volhard focused her career on studying the genetic control of development in the fruit fly Drosophila melanogaster. In 1988, Nusslein-Volhard identified the first described morphogen, a

Christiane Nusslein-Volhard studied how genes control embryonic development in flies and in fish in Europe during the twentieth and twenty-first centuries. In the 1970s, Nusslein-Volhard focused her career on studying the genetic control of development in the fruit fly Drosophila melanogaster. In 1988, Nusslein-Volhard identified the first described morphogen, a protein coded by the gene bicoid in flies. In 1995, along with Eric F. Wieschaus and Edward B. Lewis, she received the Nobel Prize in Physiology or Medicine for the discovery of genes that establish the body plan and segmentation in Drosophila. Nusslein-Volhard also investigated the genetic control of embryonic development to zebrafish, further generalizing her findings and helping establishing zebrafish as a model organism for studies of vertebrate development.

Created2012-02-16
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Lysogenic bacteria, or virus-infected bacteria, were the primary experimental models used by scientists working in the laboratories of the Pasteur Institute in Paris, France, during the 1950s and 1960s. Historians of science have noted that the use of lysogenic bacteria as a model in microbiological research influenced the scientific achievements

Lysogenic bacteria, or virus-infected bacteria, were the primary experimental models used by scientists working in the laboratories of the Pasteur Institute in Paris, France, during the 1950s and 1960s. Historians of science have noted that the use of lysogenic bacteria as a model in microbiological research influenced the scientific achievements of the Pasteur Institute's scientists. Francois Jacob and Jacques Monod used lysogenic bacteria to develop their operon model of gene regulation, to investigate the cellular regulatory mechanisms of the lysogenic life cycle, and to infer the process of cellular differentiation in the development of more complex eukaryotes.

Created2014-10-10