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Dictyostelium discoideum

Dictyostelium discoideum is a cellular slime mold that serves as an important model organism in a variety of fields. Cellular slime molds have an unusual life cycle. They exist as separate amoebae, but after consuming all the bacteria in their area they proceed to stream together to form a multicellular organism. These features make it a valuable tool for studying developmental processes and also for investigating the evolution of multicellularity. Long thought to be a type of fungus, it has recently been shown that slime molds in fact bear no relation to fungi.

Format: Articles

Subject: Organisms

The Roslin Institute (1993- )

The Roslin Institute was established in 1993 in the village of Roslin, Scotland, as an independent research center by the Biotechnology and Biological Sciences Research Council (BBSRC), and as of 2014 is part of the University of Edinburgh in Edinburgh, Scotland. Researchers at the Roslin Institute cloned the Dolly the sheep in 1996. According to the Roslin Institute, Dolly was the first mammal to develop into an adult from the transfer of the nucleus of an adult sheep cell into an ovum with the nucleus removed.

Format: Articles

Subject: Organizations

Edward Drinker Cope (1840-1897)

Edward Drinker Cope studied fossils and anatomy in the US in the late nineteenth century. Based on his observations of skeletal morphology, Cope developed a novel mechanism to explain the law of parallelism, the idea that developing organisms successively pass through stages resembling their ancestors. Others had proposed the addition of new body forms at the end of an individual organism's developed as a mechanism through which new species arose, but those proposals relied on changes in the lengths of gestation or incubation.

Format: Articles

Subject: People

The Pasteur Institute (1887- )

L'Institut Pasteur (The Pasteur Institute) is a non-profit private research institution founded by Louis Pasteur on 4 June 1887 in Paris, France. The Institute's research focuses on the study of infectious diseases, micro-organisms, viruses, and vaccines. As of 2014, ten scientists have received Nobel Prizes in physiology or medicine for the research they have done at the Pasteur Institute.

Format: Articles

Subject: Organizations

"The Potency of the First Two Cleavage Cells in Echinoderm Development. Experimental Production of Partial and Double Formations" (1891-1892), by Hans Driesch

Hans Adolf Eduard Driesch was a late-nineteenth and early-twentieth century philosopher and developmental biologist. In the spring of 1891 Driesch performed experiments using two-celled sea urchin embryos, the results of which challenged the then-accepted understanding of embryo development. Driesch showed that the cells of an early embryo, when separated, could each continue to develop into normal larval forms.

Format: Articles

Subject: Experiments, Publications

Walter Jakob Gehring (1939-2014)

Walter Jakob Gehring discovered the homeobox, a DNA segment found in a specific cluster of genes that determine the body plan of animals, plants, and fungi. Gehring identified the homeobox in 1983, with the help of colleagues while isolating the Antennapedia (Antp) gene in fruit flies (Drosophila) at the University of Basel in Basel, Switzerland. Hox genes, a family of genes that have the homeobox, determine the head-to-tail (anterior-posterior) body axis of both vertebrates and invertebrates.

Format: Articles

Subject: People

The Effects of Bisphenol A on Embryonic Development

Bisphenol A (BPA) is an organic compound that was first synthesized by Aleksandr Dianin, a Russian chemist from St. Petersburg, in 1891. The chemical nomenclature of BPA is 2,2-bis (4-hydroxyphenyl) propane. The significance of this synthesized compound did not receive much attention until 1936, when two biochemists interested in endocrinology, Edward Dodds and William Lawson, discovered its ability to act as an estrogen agonist in ovariectomized, estrogen-deficient rats.

Format: Articles

Subject: Disorders, Reproduction

Otto Rank (1884–1939)

Otto Rank studied how birth impacts individuals’ psychology and creates anxiety throughout their lives in Europe and the US during the nineteenth century. In his book The Trauma of Birth, Rank stated that birth was extremely traumatic and that one spent his or her whole life trying to recover from the experience of being born and harshly separated from the peaceful womb. He argued that the trauma experienced at birth is the source of all human suffering and the key to understanding anxiety later in life.

Format: Articles

Subject: People

Matthew Stanley Meselson (1930– )

Matthew Stanley Meselson conducted DNA and RNA research in the US during the twentieth and twenty-first centuries. He also influenced US policy regarding the use of chemical and biological weapons. Meselson and his colleague Franklin Stahl demonstrated that DNA replication is semi-conservative. Semi-conservative replication means that every newly replicated DNA double helix, which consists of two individual DNA strands wound together, contains one strand that was conserved from a parent double helix and that served as a template for the other strand.

Format: Articles

Subject: People

Dinosaur Egg Parataxonomy

Dinosaur egg parataxonomy is a classification system that organizes dinosaur eggs by descriptive features such as shape, size, and shell thickness. Though egg parataxonomy originated in the nineteenth century, Zi-Kui Zhao from Beijing, China, developed a modern parataxonomic system in the late twentieth century. Zhao's system, published in 1975, enabled scientists to organize egg specimens according to observable features, and to communicate their findings.

Format: Articles

Subject: Theories

Aristotle (384-322 BCE)

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.

Format: Articles

Subject: People

Viktor Hamburger's Study of Central-Peripheral Relations in the Development of Nervous System

An important question throughout the history of embryology is whether the formation of a biological structure is predetermined or shaped by its environment. If both intrinsic and environmental controls occur, how exactly do the two processes coordinate in crafting specific forms and functions? When Viktor Hamburger started his PhD study in embryology in the 1920s, few neuroembryologists were investigating how the central neurons innervate peripheral organs.

Format: Articles

Subject: Experiments

Pre- and Post-natal Growth Deficiencies and Fetal Alcohol Syndrome

Maternal consumption of alcohol (ethanol) during pregnancy can inhibit prenatal growth, resulting in fetuses that are small for gestational age. Those prenatal growth deficiencies can have lasting consequences for early childhood development and are often reflected by low weight and stature. Those alcohol-induced pre- and post-natal growth deficiencies ("failure to thrive") are among the abnormal developmental criteria used to identify Fetal Alcohol Syndrome (FAS). FAS is characterized by minor facial abnormalities and deficiencies of the central nervous system as well.

Format: Articles

Subject: Disorders

The Origin of Species: "Chapter Thirteen: Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs" (1859), by Charles R. Darwin

Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs is the thirteenth chapter of Charles Darwin's book The Origin of Species, first published in England in 1859. The book details part of Darwin's argument for the common ancestry of life and natural selection as the cause of speciation. In this chapter, Darwin summarizes the evidence for evolution by connecting observations of development in organisms to the processes of natural selection.

Format: Articles

Subject: Publications

De ovi mammalium et hominis genesi (1827), by Karl Ernst von Baer

De ovi mammalium et hominis genesi (On the Genesis of the Ovum of Mammals and of Men) is an 1827 pamphlet by Karl Ernst von Baer about the anatomical observation and description of the egg (ovum) of mammals, like dogs and humans. The pamphlet detailed evidence for the existence of the ovum at the beginning of the developmental process in mammals.

Format: Articles

Subject: Publications

Nicole Marthe Le Douarin (1930- )

Nicole Marthe Le Douarin was one of the first progressive female pioneers of developmental and embryological research. Some of her most notable and ground-breaking work involves grafting quail and chicken embryos together in order to study the developmental fate of each contributing embryo. Le Douarin was born in Brittany, France, on 20 August 1930. As an only child she was inspired by her mother, a school teacher at the time, to develop a passion for learning.

Format: Articles

Subject: People

Stanley Alan Plotkin's Development of a Rubella Vaccine (1969)

In the US during the late 1960s, Stanley Alan Plotkin, John D. Farquhar, Michael Katz, and Fritz Buser isolated a strain of the infectious disease rubella and developed a rubella vaccine with a weakened, or attenuated, version of the virus strain. Rubella, also called German measles, is a highly contagious disease caused by the rubella virus that generally causes mild rashes and fever. However, in pregnant women, rubella infections can lead to developmental defects in their fetuses.

Format: Articles

Subject: Experiments

Impact of Air Pollution on Reproductive Health” (1999), by Radim Srám

In 1999, researcher Radim Srám, sometimes spelled Radim Šrám, published his article “Impact of Air Pollution on Reproductive Health” in the journal Environmental Health Perspectives. In the article, Srám analyzes the effects of exposure to air pollution, which can include harmful chemicals, on fetal growth and development. Srám discusses how industrialized countries such as the US and China have led to an increase in the global amount of respirable air pollutants.

Format: Articles

Subject: Publications

The Discovery of p53 Protein

The p53 protein acts as a pivotal suppressor of inappropriate cell proliferation. By initiating suppressive effects through induction of apoptosis, cell senescence, or transient cell-cycle arrest, p53 plays an important role in cancer suppression, developmental regulation, and aging. Its discovery in 1979 was a product of research into viral etiology and the immunology of cancer. The p53 protein was first identified in a study of the role of viruses in cancer through its ability to form a complex with viral tumor antigens.

Format: Articles

Subject: Experiments

Thesis: The Hwang Woo-Suk Scandal and the Development of Bioethics in South Korea

In 2004, the South Korean geneticist Woo-Suk Hwang published what was widely regarded as the most important research finding in biotechnology that year. In the prestigious American journal Science, he claimed that he had succeeded in cloning a human blastocyst, which is an embryo in its early developmental stages (Hwang et al. 2004). A year later, in a second Science article, he made the earth-shattering announcement that he had derived eleven embryonic stem cell lines using his cloning technique (Hwang et al. 2005). The international scientific community was stunned.

Format: Essays and Theses

Subject: Ethics, People

Studies of Thalidomide's Effects on Rodent Embryos from 1962-2008

Thalidomide is a sedative drug introduced to European markets on 1 October 1957 after extensive testing on rodent embryos to ensure its safety. Early laboratory tests in rodent populations showed that pregnant rodents could safely use it, so doctors prescribed Thalidomide to treat morning sickness in pregnant women. However, in humans Thalidomide interfered with embryonic and fetal development in ways not observed in rodent tests.

Format: Articles

Subject: Organisms, Reproduction, Disorders

Susceptibility Assay

Charles Manning Child designed an experimental test, the susceptibility assay, to measure the effects of different toxins on developmental processes. The susceptibility assay measured an organism s vulnerability to death when it was submerged in a noxious solution. The assay involved immersing an organism in a solution that contained a depressant or inhibitory substance, such as alcohol, and then measuring the responses of the organism. Child interpreted these measurements as revealing information about the relative levels of metabolic activity within the organism.

Format: Articles

Subject: Technologies

"The Multi-Dimensional Human Embryo"

The Multi-Dimensional Human Embryo website (http://embryo.soad.umich.edu/) is a publicly accessible online database of the first three-dimensional images and animations of human embryos during different stages of development. Both the images and animations were created using magnetic resonance microscopy and compiled for easy access.

Format: Articles

Subject: Outreach, Organizations

"Contributions to the Development of the Embryo. On the Artificial Production of One of the First Two Blastomeres, and the Later Development (Postgeneration) of the Missing Half of the Body" (1888), by Wilhelm Roux

Wilhelm Roux was an influential figure in the early history of experimental embryology. Although he originally studied medicine, he was invited to be a Privatdozentur, or unsalaried lecturer, at the Anatomical Institute in Breslau (Wroclaw), Poland, in 1879. He spent the next ten years at this institute, working his way from Dozent to associate professor and finally, in 1889, to director for his own institute, Institut für Entwicklungsgeschichte, or Institute for Developmental History and Mechanics.

Format: Articles

Subject: Experiments

Moore v. Regents of the University of California (1990)

On 9 July 1990, in Moore v. Regents of the University of California, the Supreme Court of California ruled in a four-to-three decision that individuals do not have rights to a share in profits earned from research performed on their bodily materials. In its decision, the Supreme Court of California ruled that cancer patient John L. Moore did not have personal property rights to samples or fluids that his physicians took from his body for research purposes.

Format: Articles

Subject: Legal, Ethics