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Francis Galton (1822-1911)

Sir Francis Galton was a British science writer and amateur researcher of the late nineteenth century. He contributed greatly to the fields of statistics, experimental psychology and biometry. In the history of biology, Galton is widely regarded as the originator of the early twentieth century eugenics movement. Galton published influential writings on nature versus nurture in human personality traits, developed a family study method to identify possible inherited traits, and devised laws of genetic inheritance prior to the rediscovery of Gregor Mendel's work.

Format: Articles

Subject: People, Reproduction

Sterilization Act of 1924

The passage of the Virginia Sterilization Act of 1924 demonstrates how science has been used to drive policy throughout history. In the case of the Virginia sterilization law, the science used to draft the law was based on the principles of eugenics. With the help of Harry Laughlin's Model Sterilization Law, the state of Virginia was able to pass its own law allowing sterilization of the feebleminded, expressing sterilization as a health issue that needed to be protected from the public.

Format: Articles

Subject: Legal, Reproduction

Ethics of Designer Babies

A designer baby is a baby genetically engineered in vitro for specially selected traits, which can vary from lowered disease-risk to gender selection. Before the advent of genetic engineering and in vitro fertilization (IVF), designer babies were primarily a science fiction concept. However, the rapid advancement of technology before and after the turn of the twenty-first century makes designer babies an increasingly real possibility.

Format: Articles

Subject: Ethics, Reproduction

Alexis Carrel's Immortal Chick Heart Tissue Cultures (1912-1946)

In an effort to develop tissue culture techniques for long-term tissue cultivation, French surgeon and biologist Alexis Carrel, and his associates, produced and maintained a series of chick heart tissue cultures at the Rockefeller Institute in New York City. From 1912 to 1946, this series of chick heart tissue cultures remained alive and dividing. Since the duration of this culture greatly exceeded the normal chick life span, the cells were deemed immortal.

Format: Articles

Subject: Experiments

Parasitic Twins

Parasitic twins, a specific type of conjoined twins, occurs when one twin ceases development during gestation and becomes vestigial to the fully formed dominant twin, called the autositic twin. The underdeveloped twin is called parasitic because it is only partially formed, is not functional, or is wholly dependent on the autositic twin.

Format: Articles

Subject: Disorders, Reproduction

Effects of Prenatal Alcohol Exposure on Basal Ganglia Development

Prenatal exposure to alcohol (ethanol) in human and animal models results in a range of alcohol-induced developmental defects. In humans, those collective birth defects are called Fetal Alcohol Spectrum Disorders, with the most severe manifestation being Fetal Alcohol Syndrome (FAS). FAS is defined by pre- and post-natal growth retardation, minor facial abnormalities, and deficiencies in the central nervous system (CNS). The basal ganglia, one of the central nervous system components, are affected by exposure to ethanol during development.

Format: Articles

Subject: Disorders, Reproduction

Litowitz v. Litowitz [Brief] (2002)

Pursuant to an express provision of the embryo disposition contract they both signed, a husband and wife had to petition the court for instructions because they could not reach an agreement about what to do with frozen embryos when they divorced. The trial court awarded the pre-embryos to the husband and the Court of Appeals affirmed this decision. However, the Washington Supreme Court ruled that the pre-embryos should be thawed out and allowed to expire because the dispute had not been resolved within a five year time frame prescribed by the Cryopreservation Agreement.

Format: Articles

Subject: Legal, Reproduction

York v. Jones (1989)

In the case York v. Jones (1989), the United States District Court for the Eastern District of Virginia was one of the first US courts to address a dispute over a cryopreserved preembryo. Steven York and Risa Adler-York (the Yorks), a married couple, provided their gametes to doctors who created the preembryo, which the court referred to as a pre-zygote, as part of an in vitro fertilization (IVF) program at the Howard and Georgeanna Jones Institute for Reproductive Medicine (Jones Institute) in Norfolk, Virginia.

Format: Articles

Subject: Legal

Hamburger-Hamilton Staging Series (1951)

In 1951 Viktor Hamburger and Howard Hamilton created an embryonic staging series from a combination of photographs and drawings from other researchers. The Hamburger-Hamilton stages are a sequence of images depicting 46 chronological stages in chick development. The images begin with a fertilized egg and end with a fully developed chick. The Hamburger-Hamilton staging series was produced in order to replace a previous chick staging series created in 1900. The earlier attempt lacked specific details and staged the chick embryo by using only morphological characteristics.

Format: Articles

Subject: Processes

Homeobox Genes and the Homeobox

Homeobox genes are a cluster of regulatory genes that are spatially and temporally expressed during early embryological development. They are interesting from both a developmental and evolutionary perspective since their sequences are highly conserved and shared across an enormously wide array of living taxa.

Format: Articles

Subject: Processes

Circulatory Changes at Birth

When placental mammals are born their circulatory systems undergo radical changes as the newborns are prepared for independent life. The lungs are engaged, becoming the primary source of fresh oxygen, replacing the placental barrier as a means for blood-gas exchange.

Format: Articles

Subject: Processes

Leonardo da Vinci's Embryological Annotations

Among his myriad scientific and artistic contributions, Leonardo da Vinci's work in embryology was groundbreaking. He observed and diagramed the previously undemonstrated position of the fetus in the womb with detailed accompanying annotations of his observations. Leonardo was highly paranoid of plagiarism and wrote all of his notes in mirror-like handwriting laden with his own codes, making his writing difficult to discern and delaying its impact.

Format: Articles

Subject: Publications

Artificial Parthenogenesis and Fertilization (1913), by Jacques Loeb

Jacques Loeb is best known for his embryological work investigating parthenogenesis in invertebrates. Artificial Parthenogenesis and Fertilization is a revised and English-translated work from his earlier book, Die chemische Entwicklungserregung des tierischen Eies (1900). Artificial Parthenogenesis describes Loeb's many and varied methodical experiments to initiate egg development without fertilization by sperm. As is true with much of science, some of Loeb's experiments were successful and many were not.

Format: Articles

Subject: Publications

"The Cell-Theory" (1853), by Thomas Henry Huxley

The Cell-Theory was written by Thomas Henry Huxley in Britain and published in 1853 by The British and Foreign Medico-Chirurgical Review. The twenty-two page article reviews twelve works on cell theory, including those in Germany by Caspar Friedrich Wolff in the eighteenth century and by Karl Ernst von Baer in the nineteenth century. Huxley spends much of The Cell-Theory on a cell theory proposed in the late 1830s by Matthias Schleiden and Theodor Schwann in Germany.

Format: Articles

Subject: Publications

"Experiments in Plant Hybridization" (1866), by Johann Gregor Mendel

During the mid-nineteenth century, Johann Gregor Mendel experimented with pea plants to develop a theory of inheritance. In 1843, while a monk in the Augustian St Thomas's Abbey in Brünn, Austria, now Brno, Czech Repubic, Mendel examined the physical appearance of the abbey's pea plants (Pisum sativum) and noted inconsistencies between what he saw and what the blending theory of inheritance, a primary model of inheritance at the time, predicted.

Format: Articles

Subject: Experiments

In the Matter of the Marriage of Dahl and Angle (2008)

In the 2008 court case In the Matter of the Marriage of Dahl and Angle, the Court of Appeals of Oregon upheld a written in vitro fertilization (IVF) consent form signed by Laura and Darrell Angle, who had each contributed their genetic material to the creation of several preembryos during their marriage. Its decision followed the general framework for resolving such disputes provided by the Supreme Court of Tennessee in Davis v. Davis in 1992, which was subsequently followed by many courts across the US.

Format: Articles

Subject: Legal

"Cellular death in morphogenesis of the avian wing" (1962), by John W. Saunders Jr., et al.

In the early 1960s, John W. Saunders Jr., Mary T. Gasseling, and Lilyan C. Saunders in the US investigated how cells die in the developing limbs of chick embryos. They studied when and where in developing limbs many cells die, and they studied the functions of cell death in wing development. At a time when only a few developmental biologists studied cell death, or apoptosis, Saunders and his colleagues showed that researchers could use embryological experiments to uncover the causal mechanisms of apotosis.

Format: Articles

Subject: Experiments

Paul Kammerer's Experiments on the Midwife Toad (1905-1910)

In the first decade of the twentieth century, Paul Kammerer, a zoologist working at the Vivarium in Vienna, Austria, conducted research on developmental mechanisms, including a series of breeding experiments on toads (Alytes obstetricans). Kammerer claimed that his results demonstrated that organisms could transmit acquired characteristics to their offspring.

Format: Articles

Subject: Experiments

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

Texas Medical Providers Performing Abortion Services v. Lakey (2012)

In the 2012 case Texas Medical Providers Performing Abortion Services v. David Lakey, a US appeals court ruled as constitutional a Texas law that required abortion providers in the state to show women receiving abortions the ultrasound images of their fetuses. The law also required providers to describe the sounds of the fetuses' nascent hearts. In doing so, the court set precedent that ultrasound readings are necessary medical information for pregnant women seeking abortions, increasing the wait-period for women seeking abortions.

Format: Articles

Subject: Legal

Transposition of the Great Arteries (TGA)

Transposition of the great arteries or TGA is a potentially fatal congenital heart malformation where the pulmonary artery and the aorta are switched. The switch means that the aorta, which normally carries oxygenated blood, carries deoxygenated blood. There are two types of the malformation, d-TGA where no oxygen reaches the body and l-TGA where some oxygenated blood circulates. In the US, the Centers for Disease Control estimate that about 1,901 infants are born each year with TGA, or about one for every 2,000 births.

Format: Articles

Subject: Disorders

Anthony Comstock (1844–1915)

Anthony Comstock was a US postal inspector and politician who advocated for the suppression of obscenity and vice throughout the late nineteenth century and early twentieth century. Comstock considered any sexually explicit material like pornography and literature related to birth control and abortion as obscene. In 1873, Comstock lobbied US Congress to pass an anti-obscenity law titled An Act for the Suppression of Trade in, and Circulation of, Obscene Literature and Articles of Immoral Use, also called the Comstock Act.

Format: Articles

Subject: People

Amphioxus, and the Mosaic Theory of Development (1893), by Edmund Beecher Wilson

Edmund Beecher Wilson experimented with Amphioxus (Branchiostoma) embryos in 1892 to identify what caused their cells to differentiate into new types of cells during the process of development. Wilson shook apart the cells at early stages of embryonic development, and he observed the development of the isolated cells. He observed that in the normal development of Amphioxus, all three main types of symmetry, or cleavage patterns observed in embryos, could be found. Wilson proposed a hypothesis that reformed the Mosaic Theory associated with Wilhelm Roux in Germany.

Format: Articles

Subject: Experiments

“Family Limitations” (1914), by Margaret Higgins Sanger

In 1914, Margaret Sanger published “Family Limitations,” a pamphlet describing six different types of contraceptive methods. At the time Sanger published the pamphlet, the federal Comstock Act of 1873 had made distributing contraceptive and abortion information through the US postal service illegal. The Comstock Act classified contraceptive information as obscene and limited the amount of information available to individuals about preventing pregnancies.

Format: Articles

Subject: Publications

The Development of Mifepristone for Use in Medication Abortions

In the 1980s, researchers at the pharmaceutical company Roussel-Uclaf in Paris, France, helped develop a biological compound called mifepristone. When a woman takes it, mifepristone interferes with the function of hormones involved in pregnancy and it can therefore be used to terminate pregnancies. In 2000, the US Food and Drug Administration approved mifepristone, also called RU 486, as part of a treatment to induce abortions using drugs instead of surgery, a method called medication abortion.

Format: Articles

Subject: Reproduction