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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

Mesenchyme

Mesenchyme is a type of animal tissue comprised of loose cells embedded in a mesh of proteins and fluid, called the extracellular matrix. The loose, fluid nature of mesenchyme allows its cells to migrate easily and play a crucial role in the origin and development of morphological structures during the embryonic and fetal stages of animal life. Mesenchyme directly gives rise to most of the body's connective tissues, from bones and cartilage to the lymphatic and circulatory systems.

Format: Articles

Subject: Processes

Clomiphene Citrate

Clomiphene citrate, more commonly known by its brand names Clomid and Serophene, is a medication prescribed to women to stimulate ovulation in order to treat infertility. It stimulates ovulation in women who do not ovulate or ovulate irregularly. This drug was created by Dr. Frank Palopoli in 1956 while he worked for Merrell Company. It first successfully induced ovulation in women in 1961 and was approved by the Federal and Drug Administration (FDA) in 1967.

Format: Articles

Subject: Technologies

Hermaphrodites and the Medical Invention of Sex (1998), by Alice Domurat Dreger

Hermaphrodites and the Medical Invention of Sex, by historian of science Alice Domurat Dreger, was published in 1998 by Harvard University Press. In the book, Dreger describes how many doctors and scientists treated human hermaphrodites from the late nineteenth century to the early twentieth century. She states that during this time period, many physicians and scientists struggled to determine the nature sex, and to support a classification of sex as male or female, many physicians and scientists resorted to viewing a person's gonads for identification of his or her sex.

Format: Articles

Subject: Publications, Theories, Disorders

Francis Maitland Balfour (1851-1882)

During the 1870s and early 1880s, the British morphologist Francis Maitland Balfour contributed in important ways to the budding field of evolutionary embryology, especially through his comparative embryological approach to uncovering ancestral relationships between groups. As developmental biologist and historian Brian Hall has observed, the field of evolutionary embryology in the nineteenth century was the historical ancestor of modern-day evolutionary developmental biology.

Format: Articles

Subject: People

Wilhelm Ludvig Johannsen (1857-1927)

Wilhelm Ludvig Johannsen studied plants and helped found the field of genetics, contributing methods and concepts to the study of heredity around the turn of the twentieth century in Denmark. His experiments on heredity and variation in plants influenced the methods and techniques of geneticists, and his distinction between the genotype of an organism-its hereditary disposition-and its phenotype-its observable characteristics-remains at the core of contemporary biology. Johannsen criticized biological explanations that relied on concepts such as vitalism and teleology.

Format: Articles

Subject: People

Emma Goldman (1869–1940)

Emma Goldman was a traveling public speaker and writer known for her anarchist political views as well as her opinions on contraception and birth limiting in the late nineteenth century in the United States. Goldman identified as an anarchist, which she explained as being part of an ideology in which people use violence to provoke or demand social and political change. Goldman was involved in many anarchist social groups and published the anarchist magazine Mother Earth.

Format: Articles

Subject: People

Fortunio Liceti (1577–1657)

Fortunio Liceti studied natural philosophy and medicine in Italy during the first half of the seventeenth century. Liceti wrote greater than seventy works on a wide range of topics, including the human soul, reproduction, and birth defects observed in animals and human infants. In the seventeenth century, people commonly addressed birth defects using superstition and considered them as signs of evil, possibly caused by spiritual or supernatural entities. Liceti described infants with birth defects as prodigies and monsters to be admired and studied rather than feared.

Format: Articles

Subject: People

Clinical Tests of Estrogen Injections on Women with Abnormal Menstrual Cycles During the Early 1920s by Jean Paul Pratt and Edgar Allen

In the early twentieth century US, Jean Paul Pratt and Edgar Allen conducted clinical experiments on women who had abnormal menstrual cycles. During the clinical tests, researchers injected the hormone estrogen into their patients to alleviate their menstrual ailments, which ranged from irregular cycles to natural menopause. The hormone estrogen plays a prominent role in the menstrual cycle by signaling the tissue lining the uterus (endometrium) to thicken in preparation for possible pregnancy.

Format: Articles

Subject: Experiments

“Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid” (1953), by James Watson and Francis Crick

In April 1953, James Watson and Francis Crick published “Molecular Structure of Nucleic Acids: A Structure of Deoxyribose Nucleic Acid” or “A Structure for Deoxyribose Nucleic Acid,” in the journal Nature. In the article, Watson and Crick propose a novel structure for deoxyribonucleic acid or DNA. In 1944, Oswald T. Avery and his group at Rockefeller University in New York City, New York published experimental evidence that DNA contained genes, the biological factors called genes that dictate how organisms grow and develop.

Format: Articles

Subject: Publications

“Molecular Configuration in Sodium Thymonucleate” (1953), by Rosalind Franklin and Raymond Gosling

In April 1953, Rosalind Franklin and Raymond Gosling, published “Molecular Configuration in Sodium Thymonucleate,” in the scientific journal Nature. The article contained Franklin and Gosling’s analysis of their X-ray diffraction pattern of thymonucleate or deoxyribonucleic acid, known as DNA. In the early 1950s, scientists confirmed that genes, the heritable factors that control how organisms develop, contained DNA. However, at the time scientists had not determined how DNA functioned or its three-dimensional structure.

Format: Articles

Subject: Publications

"In vitro Experiments on the Effects of Mouse Sarcomas 180 and 37 on the Spinal and Sympathetic Ganglia of the Chick Embryo" (1954), by Rita Levi-Montalcini, Viktor Hamburger, and Hertha Meyer

"In vitro Experiments on the Effects of Mouse Sarcomas 180 and 37 on the Spinal and Sympathetic Ganglia of the Chick Embryo" were experiments conducted by Rita Levi-Montalcini in conjunction with Viktor Hamburger and Hertha Meyer and published in Cancer Research in 1954. In this series of experiments, conducted at the University of Brazil, Levi-Montalcini demonstrated increased nerve growth by introducing specific tumors (sarcomas) to chick ganglia. Ganglia are clusters of nerve cells, from which nerve fibers emerge.

Format: Articles

Subject: Experiments

Edward Charles Dodds (1899-1973)

Edward Charles Dodds researched the function and effects of natural and artificial hormones on the endocrine system in England during the twentieth century. Though he first worked with hormones such as insulin, Dodds focused on the effects of estrogen in the body and how to replicate those effects with artificial substances. In 1938, along with chemist Robert Robinson, Dodds synthesized the first synthetic estrogen called diethylstilbestrol.

Format: Articles

Subject: People

Casti Connubii (1930), by Pope Pius XI

"Casti Connubii," a papal encyclical given by Pope Pius XI on 31 December 1930, served primarily as a reaffirmation and expansion of the issues discussed in Arcanum, an encyclical written by Pope Leo XIII. It was released to address new threats to marriage and conjugal unity, and indeed is translated "On Christian Marriage" or "On Chastity in Marriage." The document explores the meaning of Christian marriage and emphasizes its threefold purpose as borrowed from St.

Format: Articles

Subject: Religion

Lydia Estes Pinkham (1819–1883)

Lydia Estes Pinkham invented and sold Lydia Pinkham’s Vegetable Compound, a medicinal tonic used to treat menstrual discomfort and promote female reproductive health in general, in the US during the nineteenth century. Pinkham also founded Mrs. Lydia E. Pinkham Medicine Company, a business that sold natural remedies for women’s health issues. Throughout her life, Pinkham acted as an authority on female wellness, writing medical pamphlets about female anatomy and reproductive processes.

Format: Articles

Subject: People

“Genetical Implications of the Structure of Deoxyribonucleic Acid” (1953), by James Watson and Francis Crick

In May 1953, scientists James Watson and Francis Crick wrote the article “Genetical Implications of the Structure of Deoxyribonucleic Acid,” hereafter “Genetical Implications,” which was published in the journal Nature.

Format: Articles

Subject: Publications

“Perspectives on the Properties of Stem Cells” (2005), by Ernest McCulloch and James Till

In 2005, Ernest McCulloch and James Till published the article “Perspectives on the Properties of Stem Cells,” which discusses the various properties and future possibilities for the use of stem cells. Stem cells are unspecialized cells that can develop into several different cell types. In the article published in the journal Nature on 1 October 2005, the authors say they wrote the article to dispel misconceptions about what stem cells are, what they do, address some controversies surrounding stem cells, and discuss potential uses of stem cells.

Format: Articles

Subject: Publications

The Time Has Come: A Catholic Doctor's Proposals to End the Battle over Birth Control (1963), by John Rock

In 1963, Roman Catholic fertility doctor John Rock published The Time Has Come: A Catholic Doctor's Proposals to End the Battle over Birth Control, a first-person treatise on the use of scientifically approved forms of birth control for Catholic couples. The first contraceptive pill, called Enovid, had been on the market since June 1960, and Rock was one of the leading researchers in its development. In The Time Has Come, Rock explicitly describes the arguments for and against the use of birth control from both a religious and a scientific perspective.

Format: Articles

Subject: Publications, Religion, Reproduction

Spemann-Mangold Organizer

The Spemann-Mangold organizer, also known as the Spemann organizer, is a cluster of cells in the developing embryo of an amphibian that induces development of the central nervous system. Hilde Mangold was a PhD candidate who conducted the organizer experiment in 1921 under the direction of her graduate advisor, Hans Spemann, at the University of Freiburg in Freiburg, German. The discovery of the Spemann-Mangold organizer introduced the concept of induction in embryonic development.

Format: Articles

Subject: Processes

Johns Hopkins Fertility Center

Johns Hopkins Medical Center, located in Baltimore, Maryland, opened in 1889; its associated medical school opened four years later. Today the hospital, a leading research center, contains many departments, including a fertility center that is renowned for taking on difficult cases that have been rejected by other fertility clinics. The fertility center was founded by physician Georgeanna Seegar Jones in 1939 as the Division of Reproductive Endocrinology in the gynecology department. The division expanded once formal training in reproductive endocrinology began in 1973.

Format: Articles

Subject: Organizations, Reproduction

Abraham Trembley (1710-1784)

Abraham Trembley's discovery of the remarkable regenerative capacity of the hydra caused many to question their beliefs about the generation of organisms. Born 3 September 1710 to a prominent Geneva family, Trembley studied at the Calvin Institute, now the University of Geneva, where he completed his thesis on calculus. He went on to become tutor for Count William Bentinck's two sons, and it was while teaching the boys natural history that Trembley came across a strange organism in a sample of pond water.

Format: Articles

Subject: People

"Embryonic Stem Cell Lines Derived from Human Blastocytes" (1998), by James Thomson

After becoming chief pathologist at the University of Wisconsin-Madison Wisconsin Regional Primate Center in 1995, James A. Thomson began his pioneering work in deriving embryonic stem cells from isolated embryos. That same year, Thomson published his first paper, "Isolation of a Primate Embryonic Stem Cell Line," in Proceedings of the National Academy of Sciences of the United States of America, detailing the first derivation of primate embryonic stem cells. In the following years, Thomson and his team of scientists - Joseph Itskovitz-Eldor, Sander S. Shapiro, Michelle A.

Format: Articles

Subject: Experiments, Publications

Apoptosis in Embryonic Development

Apoptosis, or programmed cell death, is a mechanism in embryonic development that occurs naturally in organisms. Apoptosis is a different process from cell necrosis, which is uncontrolled cell death usually after infection or specific trauma. As cells rapidly proliferate during development, some of them undergo apoptosis, which is necessary for many stages in development, including neural development, reduction in egg cells (oocytes) at birth, as well as the shaping of fingers and vestigial organs in humans and other animals. Sydney Brenner, H. Robert Horvitz, and John E.

Format: Articles

Subject: Theories

Hermann Joseph Muller (1890-1967)

Hermann Joseph Muller studied the effects of x-ray radiation on genetic material in the US during the twentieth century. At that time, scientists had yet to determine the dangers that x-rays presented. In 1927, Muller demonstrated that x-rays, a form of high-energy radiation, can mutate the structure of genetic material. Muller warned others of the dangers of radiation, advising radiologists to protect themselves and their patients from radiation. He also opposed the indiscriminate use of radiation in medical and industrial fields.

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