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Gustav Jacob Born (1851-1900)

Gustav Jacob Born was an experimental embryologist whose original work with amphibians served as the platform for his wax-plate method of embryo modeling, heteroblastic (different tissues) and xenoplastic (similar species) transplantation methods, environmental influences on sex ratio studies, and proposed function of the corpus luteum. He was born 22 April 1851 in Kempen, Prussia, but his family moved to the larger city of Görlitz within a year after Born's birth. His father was Marcus Born, a physician and public health officer who practiced in the town of Görlitz.

Format: Articles

Subject: People

Carl Richard Moore (1892-1955)

Carl Richard Moore was a professor and researcher at the University of Chicago in Chicago, Illinois who studied sex hormones in animals from 1916 until his death in 1955. Moore focused on the role of hormones on sex differentiation in offspring, the optimal conditions for sperm production, and the effects of vasectomy or testicular implants on male sex hormone production. Moore's experiments to create hermaphrodites in the laboratory contributed to the theory of a feedback loop between the pituitary and fetal gonadal hormones to control sex differentiation.

Format: Articles

Subject: People

On the Generation of Animals, by Aristotle

Aristotle's On the Generation of Animals is referred to in Latin as De Generatione animalium. As with many of Aristotle's writings, the exact date of authorship is unknown, but it was produced in the latter part of the fourth century B.C. This book is the second recorded work on embryology that is treated as a subject of philosophy, being preceded by contributions in the Hippocratic corpus by about a century.

Format: Articles

Subject: Publications

John Bertrand Gurdon (1933- )

Sir John Bertrand Gurdon further developed nuclear transplantation, the technique used to clone organisms and to create stem cells, while working in Britain in the second half of the twentieth century. Gurdon's research built on the work of Thomas King and Robert Briggs in the United States, who in 1952 published findings that indicated that scientists could take a nucleus from an early embryonic cell and successfully transfer it into an unfertilized and enucleated egg cell.

Format: Articles

Subject: People

"Experimental Chimeras' Removal of Reproductive Barrier Between Sheep and Goat" (1984), by Sabine Meinecke-Tillmann and Burkhard Meinecke

In 1984 Sabine Meinecke-Tillmann and Burkhard Meinecke published their article "Experimental Chimeras - Removal of Reproductive Barrier Between Sheep and Goat" in Nature. Their study conquered the reproductive barrier between sheep and goats through embryo manipulation. Their article appeared in Nature on the same day that a similar experiment, conducted by Carole Fehilly, Steen Willadsen, and Elizabeth Tucker was published regarding reproductive barriers between sheep and goats.

Format: Articles

Subject: Experiments

John George Children (1777–1852)

John George Children described several species of insects and animals while working at the British Museum in London, England, in the eighteenth and nineteenth centuries. Children also conducted research on chemical batteries called voltaic cells and briefly studied and manufactured gunpowder. One of the species he described, the Children’s python, or Antaresia children, was used in the twenty-first century as the subject of experiments that involved the biological cost of reproduction in snakes.

Format: Articles

Subject: People

Interspecies SCNT-derived Humanesque Blastocysts

Since the 1950s, scientists have developed interspecies blastocysts in laboratory settings, but not until the 1990s did proposals emerge to engineer interspecies blastocysts that contained human genetic or cellular material. Even if these embryos were not permitted to mature to fetal stages, their ethical and political status became debated within nations attempting to use them for research.

Format: Articles

Subject: Theories

The Cell in Development and Inheritance (1900), by Edmund Beecher Wilson

The Cell in Development and Inheritance, by Edmund Beecher Wilson, provided a textbook introduction to cell biology for generations of biologists in the twentieth century. In his book, Wilson integrated information about development, inheritance, chromosomes, organelles, and the structure and functions of cells. First published in 1896, the book started with 371 pages, grew to 483 pages in the second edition that appeared in 1900, and expanded to 1,231 pages by the third and final edition in 1925.

Format: Articles

Subject: Publications

Irving Freiler Stein Sr. (1887–1976)

Irving Freiler Stein Sr. was a physician who studied women’s reproductive health during the twentieth century in the United States. In partnership with his colleague, Michael Leventhal, Stein identified a women’s reproductive disorder related to elevated male sex hormones, or androgens. The syndrome was originally called Stein-Leventhal syndrome and later known as polycystic ovarian syndrome. While studying the syndrome, Stein also helped establish a treatment for the condition, through the surgical removal of ovarian tissues.

Format: Articles

Subject: People

The Organism as a Whole: From a Physicochemical Viewpoint (1916), by Jacques Loeb

Jacques Loeb published The Organism as a Whole: From a Physicochemical Viewpoint in 1916. Loeb's goal for the book was to refute the claim that physics and chemistry were powerless to completely explain whole organisms and their seemingly goal-oriented component processes. Loeb used his new account of science and scientific explanation, marshaling evidence from his embryological researches, to show that physicochemical biology completely and correctly explained whole organisms and their component processes.

Format: Articles

Subject: Publications

Conjoined Twins

Conjoined twins are twins whose bodies are anatomically joined in utero. The degree to which the twins are attached can range from simple, involving skin and cartilage, to complex, including fusion of the skull(s), brain(s), or other vital organs. There are more than a dozen classifications of conjoined twins but what they all tend to have in common is the sharing of the chorion, placenta, and amniotic sac.

Format: Articles

Subject: Disorders, Reproduction

In re Marriage of Witten (2003)

In re Marriage of Witten, decided by the Iowa Supreme Court in 2003, held that neither Tamera nor Arthur (Trip) Witten could use or destroy several cryopreserved preembryos created during their marriage using in vitro fertilization (IVF), unless the former couple could reach a mutual agreement. Tamera and Trip Witten, unable to conceive conventionally during their marriage, had attempted to start a family together using IVF at the University of Nebraska Medical Center (UNMC) in Omaha, Nebraska.

Format: Articles

Subject: Legal

The Fruits of Philosophy (1832), by Charles Knowlton

In 1832, Charles Knowlton published The Fruits of Philosophy, a pamphlet advocating for controlling reproduction and detailing methods for preventing pregnancy. Originally published anonymously in Massachusetts, The Fruits of Philosophy was an illegal book because United States law prohibited the publishing of immoral and obscene material, which included information about contraception. In The Fruits of Philosophy, Knowlton detailed recipes for contraceptives and advocated for controlling reproduction.

Format: Articles

Subject: Publications

Lydia Pinkham’s Vegetable Compound (1873-1906)

First marketed in the US 1875, Lydia Pinkham’s Vegetable Compound was an herbal medicine used by women to relieve menstrual discomfort and menopausal symptoms in women. The herbal compound was invented by Lydia Estes Pinkham in 1873 in her home kitchen in Lynn, Massachusetts. Pinkham created the compound by mixing alcohol with roots and herbs. The compound was patented, packaged, and distributed by the Mrs. Lydia Pinkham Medicine Company in 1876. The Mrs.

Format: Articles

Subject: Technologies, Reproduction

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

Effect of Prenatal Alcohol Exposure on Radial Glial Cells

Prenatal alcohol (ethanol) exposure can have dramatic effects on the development of the central nervous system (CNS), including morphological abnormalities and an overall reduction in white matter of the brain. The impact of ethanol on neural stem cells such as radial glia (RG) has proven to be a significant cause of these defects, interfering with the creation and migration of neurons and glial cells during development.

Format: Articles

Subject: Disorders, Reproduction

The Jackson Laboratory

The Roscoe B. Jackson Laboratory, known commonly in the scientific field as the Jackson Laboratory, was founded by Clarence Cook Little in May 1929. The lab has been pivotal in research with in vitro fertilization, teratomas, gene replacement therapy for birth defects, and more because its researchers have focused from the beginning on developing the mouse as a model organism. Mice were chosen by researchers at Jackson as the best available model for genetic research, and today genetically uniform strains of mice developed at the lab are used in laboratories all over the world.

Format: Articles

Subject: Organizations

Joseph Needham (1900-1995)

Joseph Needham was an embryologist and biochemist who is most noted in science for his studies on induction in developing embryos. Needham worked with Conrad Hal Waddington to attempt to identify the compound responsible for the organizer's activity. Although he was not successful in discovering the chemical, he and Waddington learned much about the organizer. Needham was a meticulous writer, writing reviews and books about contemporary research.

Format: Articles

Subject: People

A Child Is Born (1965), by Lennart Nilsson

Dell Publishing in New York City, New York, published Lennart Nilsson's A Child Is Born in 1966. The book was a translation of the Swedish version called Ett barn blir till, published in 1965. It sold over a million copies in its first edition, and has translations in twelve languages. Nilsson, a photojournalist, documented a nine-month human pregnancy using pictures and accompanying text written by doctors Axel Ingelman-Sundberg, Claes Wirsen and translated by Britt and Claes Wirsen and Annabelle MacMillian.

Format: Articles

Subject: Outreach, Publications

Sex Determination in Humans

In humans, sex determination is the process that determines the biological sex of an offspring and, as a result, the sexual characteristics that they will develop. Humans typically develop as either male or female, primarily depending on the combination of sex chromosomes that they inherit from their parents. The human sex chromosomes, called X and Y, are structures in human cells made up of tightly bound deoxyribonucleic acid, or DNA, and proteins.

Format: Articles

Subject: Processes, Processes

Frank Rattray Lillie (1870-1947)

Frank R. Lillie was born in Toronto, Canada, on 27 June 1870. His mother was Emily Ann Rattray and his father was George Waddell Little, an accountant and co-owner of a wholesale drug company. While in high school Lillie took up interests in entomology and paleontology but went to the University of Toronto with the aim of studying ministry. He slowly became disillusioned with this career choice and decided to major in the natural sciences. It was during his senior year that he developed his lifelong interest in embryology.

Format: Articles

Subject: People

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

Intraspecies Chimeras Produced in Laboratory Settings (1960-1975)

When cells-but not DNA-from two or more genetically distinct individuals combine to form a new individual, the result is called a chimera. Though chimeras occasionally occur in nature, scientists have produced chimeras in a laboratory setting since the 1960s. During the creation of a chimera, the DNA molecules do not exchange genetic material (recombine), unlike in sexual reproduction or in hybrid organisms, which result from genetic material exchanged between two different species. A chimera instead contains discrete cell populations with two unique sets of parental genes.

Format: Articles

Subject: Organisms, Processes

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

Hartsoeker's Homunculus Sketch from Essai de Dioptrique

This embryology image is a pencil sketch by Nicolaas Hartsoeker, published as part of his 1694 French-language paper entitled Essai de Dioptrique, a semi-speculative work describing the sorts of new scientific observations that could be done using magnifying lenses. Dioptrique was published in Paris by the publishing house of Jean Anisson. The image depicts a curled up infant-like human, now referred to as a homunculus, inside the head of a sperm cell.

Format: Articles

Subject: Theories, Processes