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Edwin Stephen Goodrich (1868-1946)

Edwin Stephen Goodrich studied the structures of animals in England during the nineteenth and twentieth centuries. Goodrich studied how animals develop to identify their parts and to establish the evolutionary relationships between different species. Goodrich established that body structures can shift their positions relative to an organism's body during evolution, and he hypothesized that body structures can share ancestry (homology) between organisms of different species, even without identical body placement.

Format: Articles

Subject: People

Edwin Carlyle (Carl) Wood (1929–2011)

Edwin Carlyle Wood, also known as Carl Wood, was a physician who helped develop in vitro fertilization, or IVF, treatments. From 1964 to 1992, Wood worked as a professor of obstetrics and gynecology at Monash University in Melbourne, Australia, where he was one of the first in the world to lead a team of physicians to establish IVF as a proven treatment for infertility. IVF refers to a medical procedure in which scientists inseminate an egg cell with a sperm cell outside of the body, such as in a glass dish in a clinical setting.

Format: Articles

Subject: People, Technologies, Reproduction

G. B. Ray

Format: Photographs

Subject: People

“Female Ejaculation: A Case Study” (1981), by Frank Addiego, Edwin G. Belzer Jr., Jill Comolli, William Moger, John D. Perry, and Beverly Whipple

In 1981, Frank Addiego and colleagues published “Female Ejaculation: A Case Study” in The Journal of Sex Research. In the article, the authors find that female ejaculation, or the expulsion of fluid from a female’s urethra during or before orgasm, is a legitimate phenomenon that can occur when one stimulates an area in the vaginal wall that the team names the Gräfenberg-spot. According to the authors, at the time of publication, many individuals believed that if a female expelled fluid during orgasm, the fluid was urine and, thus, improper bladder control caused the expulsions.

Format: Articles

Subject: Publications, Processes, Reproduction

Germ Layers

A germ layer is a group of cells in an embryo that interact with each other as the embryo develops and contribute to the formation of all organs and tissues. All animals, except perhaps sponges, form two or three germ layers. The germ layers develop early in embryonic life, through the process of gastrulation. During gastrulation, a hollow cluster of cells called a blastula reorganizes into two primary germ layers: an inner layer, called endoderm, and an outer layer, called ectoderm.

Format: Articles

Subject: Theories, Processes

Endoderm

Endoderm is one of the germ layers-- aggregates of cells that organize early during embryonic life and from which all organs and tissues develop. All animals, with the exception of sponges, form either two or three germ layers through a process known as gastrulation. During gastrulation, a ball of cells transforms into a two-layered embryo made of an inner layer of endoderm and an outer layer of ectoderm. In more complex organisms, like vertebrates, these two primary germ layers interact to give rise to a third germ layer, called mesoderm.

Format: Articles

Subject: Processes

“Use of reproductive technology for sex selection for nonmedical reasons” (2015), by the Ethics Committee of the American Society for Reproductive Medicine

In June 2015, the Ethics Committee of the American Society for Reproductive Medicine, or ASRM, published “Use of reproductive technology for sex selection for nonmedical reasons” in Fertility and Sterility. In the report, the Committee presents arguments for and against the use of reproductive technology for sex selection for any reason besides avoiding sex-linked disorders, or genetic disorders that only affect a particular sex.

Format: Articles

Subject: Publications

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

Edwin J. Cohn

Format: Photographs

Subject: People

Edwin P. Lang

Format: Photographs

Subject: People

Hermann Joseph Muller's Study of X-rays as a Mutagen, (1926-1927)

Hermann Joseph Muller conducted three experiments in 1926 and 1927 that demonstrated that exposure to x-rays, a form of high-energy radiation, can cause genetic mutations, changes to an organism's genome, particularly in egg and sperm cells. In his experiments, Muller exposed fruit flies (Drosophila) to x-rays, mated the flies, and observed the number of mutations in the offspring. In 1927, Muller described the results of his experiments in "Artificial Transmutation of the Gene" and "The Problem of Genic Modification".

Format: Articles

Subject: Experiments

“A Proposed Structure for the Nucleic Acids” (1953) by Linus Pauling and Robert Brainard Corey

In February 1953, Linus Pauling and Robert Brainard Corey, two scientists working at the California Institute of Technology in Pasadena, California, proposed a structure for deoxyribonucleic acid, or DNA, in their article “A Proposed Structure for the Nucleic Acids,” henceforth “Nucleic Acids.” In the article, Pauling and Corey suggest a model for nucleic acids, including DNA, that consisted of three nucleic acid strands wound together in a triple helix.

Format: Articles

Subject: Publications

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

Sir D'Arcy Wentworth Thompson (1860-1948)

Known by many for his wide-reaching interests and keen thinking, D'Arcy Wentworth Thompson was one of Britain's leading scientific academics in the first few decades of the twentieth century. A prodigious author, Thompson published some 300 papers, books, and articles in the biological sciences, classics, oceanography, and mathematics. He was a famous lecturer and conversationalist-a true "scholar-naturalist," as his daughter wrote in her biography of her father.

Format: Articles

Subject: People

Edwin Grant Conklin (1863-1952)

Edwin Grant Conklin was born in Waldo, Ohio, on 24 November 1863 to parents Nancy Maria Hull and Dr. Abram V. Conklin. Conklin's family was very religious and he seriously considered a theistic path before choosing a career in academics. Conklin's scientific work was primarily in the areas of embryology, cytology, and morphology, though many questions regarding the relationships between science, society, and philosophy had an influence on both his writings and academic lectures.

Format: Articles

Subject: People

David Edwin Wildt (1950- )

David Edwin Wildt developed and applied assisted reproductive technologies to conserve rare and endangered wildlife species in the US during the twentieth and twenty-first centuries. He advocated genome resource banks to help preserve biodiversity, and he advocated for practical ethics to guide wildlife reproductive biologists when they use technology and environmental planning. Wildt often focused on the cheetah (Acinonyx jubatus), but he researched greater than fifty vertebrate species.

Format: Articles

Subject: People

Photograph 51, by Rosalind Franklin (1952)

On 6 May 1952, at King’s College London in London, England, Rosalind Franklin photographed her fifty-first X-ray diffraction pattern of deoxyribosenucleic acid, or DNA. Photograph 51, or Photo 51, revealed information about DNA’s three-dimensional structure by displaying the way a beam of X-rays scattered off a pure fiber of DNA. Franklin took Photo 51 after scientists confirmed that DNA contained genes. Maurice Wilkins, Franklin’s colleague showed James and Francis Crick Photo 51 without Franklin’s knowledge. Watson and Crick used that image to develop their structural model of DNA.

Format: Articles

Subject: Publications

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

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