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Charles Darwin's Theory of Pangenesis

In 1868 in England, Charles Darwin proposed his pangenesis theory to describe the units of inheritance between parents and offspring and the processes by which those units control development in offspring. Darwin coined the concept of gemmules, which he said referred to hypothesized minute particles of inheritance thrown off by all cells of the body. The theory suggested that an organism's environment could modify the gemmules in any parts of the body, and that these modified gemmules would congregate in the reproductive organs of parents to be passed on to their offspring.

Format: Articles

Subject: Theories

Temperature-Dependent Sex Determination in Reptiles

The sex of a reptile embryo partly results from the production of sex hormones during development, and one process to produce those hormones depends on the temperature of the embryo's environment. The production of sex hormones can result solely from genetics or from genetics in combination with the influence of environmental factors. In genotypic sex determination, also called genetic or chromosomal sex determination, an organism's genes determine which hormones are produced.

Format: Articles

Subject: Experiments

The First Successful Cloning of a Gaur (2000), by Advanced Cell Technology

Advanced Cell Technology (ACT), a stem cell biotechnology company in Worcester, Massachusetts, showed the potential for cloning to contribute to conservation efforts. In 2000 ACT researchers in the United States cloned a gaur (Bos gaurus), an Asian ox with a then declining wild population. The researchers used cryopreserved gaur skin cells combined with an embryo of a domestic cow (Bos taurus). A domestic cow also served as the surrogate for the developing gaur clone.

Format: Articles

Subject: Experiments

Andreas Vesalius (1514–1564)

Andreas Vesalius, also called Andries van Wesel, studied anatomy during the sixteenth century in Europe. Throughout his career, Vesalius thoroughly dissected numerous human cadavers, and took detailed notes and drawings of his research. Compiling his research, Vesalius published an anatomy work titled De humani corporis fabrica libri septem (On the fabric of the human body in seven books). The Fabrica included illustrations of dissected men, women, and uteruses with intact fetuses.

Format: Articles

Subject: People

Michael D. West (1953- )

Michael D. West is a biomedical entrepreneur and investigator whose aim has been to extend human longevity with biomedical interventions. His focus has ranged from the development of telomerase-based therapeutics to the application of human embryonic stem cells in regenerative medicine. Throughout his eventful career, West has pursued novel and sometimes provocative ideas in a fervent, self-publicizing manner. As of 2009, West advocated using human somatic cell nuclear transfer techniques to derive human embryonic stem cells for therapeutic practice.

Format: Articles

Subject: People

The Baby Makers (2012)

In 2012, the production company Waddell Media Production released the documentary The Baby Makers. The four-part series, directed and produced by Edel O’Mahony, follows multiple couples in Northern Ireland struggling with infertility problems as they utilize different treatments such as in vitro fertilization, or IVF, egg donation, and egg freezing. IVF is a procedure in which a woman’s egg is fertilized by a sperm outside of her body. Once the sperm fertilizes the egg, a fertility doctor places the fertilized egg back into the woman’s uterus.

Format: Articles

Subject: Outreach

William Thomas Astbury (1898–1961)

William Thomas Astbury studied the structures of fibrous materials, including fabrics, proteins, and deoxyribonucleic acid, or DNA, in England during the twentieth century. Astbury employed X-ray crystallography, a technique in which scientists use X-rays to learn about the molecular structures of materials. Astbury worked at a time when scientists had not yet identified DNA’s structure or function in genes, the genetic components responsible for how organisms develop and reproduce. He was one of the first scientists to use X-ray crystallography to study the structure of DNA.

Format: Articles

Subject: People

Frederik Ruysch (1638-1731)

Frederik Ruysch made anatomical drawings and collected and preserved human specimens, many of which were infants and fetuses, in the Netherlands during the seventeenth and eighteenth centuries. Ruysch had many interests, including anatomy, botany, and medicine, and he discovered structures of the lymphatic system and of the eye. His collection of preserved human specimens were used as educational tools for his students and for other physicians, and they were displayed in a museum of his own making that was open to the public.

Format: Articles

Subject: People

Body Worlds

Body Worlds is an exhibition featuring plastinates, human bodies that have been preserved using a plastination process. First displayed in 1995 in Tokyo, Japan, this collection of anatomical specimens has since been displayed around the world. Although the exhibition debuted in Japan, the idea for the displays began at Heidelberg University in Heidelberg, Germany, where anatomist Gunther von Hagens invented a technique for plastination in the 1970s. After years of research and small-scale presentations of his work, von Hagens created Body Worlds, or Korperwelten in German.

Format: Articles

Subject: Organizations

Karl Oskar Illmensee (1939–)

Karl Oskar Illmensee studied the cloning and reproduction of fruit flies, mice, and humans in the US and Europe during the twentieth and twenty-first centuries. Illmensee used nuclear transfer techniques (cloning) to create early mouse embryos from adult mouse cells, a technique biologists used in later decades to help explain how embryonic cells function during development. In the early 1980s, Illmensee faced accusations of fraud when others were unable to replicate the results of his experiments with cloned mouse embryos.

Format: Articles

Subject: People, People

Rosalind Elsie Franklin (1920-1958)

Rosalind Elsie Franklin worked with X-ray crystallography at King's College London, UK, and she helped determine the helical structure of DNA in the early 1950s. Franklin's research helped establish molecular genetics, a field that investigates how heredity works on the molecular level. The discovery of the structure of DNA also made future research possible into the molecular basis of embryonic development, genetic disorders, and gene manipulation.

Format: Articles

Subject: People

Johann Friedrich Blumenbach (1752-1840)

In eighteenth century Germany, Johann Friedrich Blumenbach studied how individuals within a species vary, and to explain such variations, he proposed that a force operates on organisms as they develop. Blumenbach used metrical methods to study the history of humans, but he was also a natural historian and theorist. Blumenbach argued for theories of the transformation of species, or the claim that new species can develop from existing forms.

Format: Articles

Subject: People

The Cabinet of Frederik Ruysch

Frederik Ruysch's cabinet of curiosities, commonly referred to simply as the Cabinet, was a museum Ruysch created in the Netherlands in the late 160ss. The Cabinet filled a series of small houses that Ruysch rented in Amsterdam and contained over 2,000 specimens, including preserved fetuses and infants. The collection remained in Amsterdam until it was purchased by Tsar Peter the Great of Russia in 1717 and transferred to St. Petersburg, Russia.

Format: Articles

Subject: Organizations, Outreach

Jeter v. Mayo (2005)

In Jeter v. Mayo, the Court of Appeals of Arizona in 2005 held that a cryopreserved, three-day-old pre-embryo is not a person for purposes of Arizona's wrongful death statutes, and that the Arizona Legislature was best suited to decide whether to expand the law to include cryopreserved pre-embryos. The Court of Appeals affirmed a decision by the Maricopa County Superior Court to dismiss a couple's wrongful death claim after the Mayo Clinic (Mayo) allegedly lost or destroyed several of their cryopreserved pre-embryos.

Format: Articles

Subject: Reproduction, Legal

Gunther von Hagens' Plastination Technique

Plastination is a technique for preserving tissues, organs, and whole bodies for medical purposes and public display. Gunther von Hagens invented a form of the method in 1977 at Heidelberg University in Heidelberg, Germany after observing medical students struggle working with cadavers that quickly decomposed. Von Hagens' body models, referred to as plastinates, have since become widely used educational tools not only for those studying anatomy and medicine, but also for the general public.

Format: Articles

Subject: Technologies

Neurospora crassa Life Cycle

This diagram shows the life cycle of Neurospora crassa, a mold that grows on bread. N. crassa can reproduce through an asexual cycle or a sexual cycle. The asexual cycle (colored as a purple circle), begins in this figure with (1a) vegetative mycelium, which are strands of mature fungus. Some of the strands form bulbs (2a) in a process called conidiation. From those bulbs develop the conidia, which are spores. Next, (3a) a single conidium separates from its strand and elongates until it forms mycelium.

Format: Graphics

Subject: Organisms, Processes, Theories

"Transfer of Fetal Cells with Multilineage Potential to Maternal Tissue" (2004), by Kiarash Khosrotehrani et al.

In 2004, a team of researchers at Tufts-New England
Medical Center in Boston, Massachusetts, investigated the fetal
cells that remained in the maternal blood stream after pregnancy.
The results were published in Transfer of Fetal Cells with
Multilineage Potential to Maternal Tissue. The team working on that
research included Kiarash Khosrotehrani, Kirby L. Johnson, Dong
Hyun Cha, Robert N. Salomon, and Diana W. Bianchi. The researchers
reported that the fetal cells passed to a pregnant woman during

Format: Articles

Subject: Experiments, Reproduction

Roger Sperry’s Split Brain Experiments (1959–1968)

In the 1950s and 1960s, Roger Sperry performed experiments on cats, monkeys, and humans to study functional differences between the two hemispheres of the brain in the United States. To do so he studied the corpus callosum, which is a large bundle of neurons that connects the two hemispheres of the brain. Sperry severed the corpus callosum in cats and monkeys to study the function of each side of the brain. He found that if hemispheres were not connected, they functioned independently of one another, which he called a split-brain.

Format: Articles

Subject: Experiments

Retinoids As Teratogens

Vitamin A (retinol) is an essential vitamin in the daily functioning of human beings that helps regulate cellular differentiation of epithelial tissue. Studies have shown that an excess of vitamin A can affect embryonic development and result in teratogenesis, or the production of birth defects in a developing embryo. Excess intake of vitamin A and retinoids by pregnant women often results malformations to fetuses' skulls, faces, limbs, eyes, central nervous system.

Format: Articles

Subject: Disorders, Reproduction

The Discovery of The Dikika Baby Fossil as Evidence for Australopithecine Growth and Development

When scientists discovered a 3.3
million-year-old skeleton of a child of the human lineage (hominin) in
2000, in the village of Hadar, Ethiopia, they were able to study growth
and development of Australopithecus
afarensis, an extinct hominin species. The team of researchers,
led by Zeresenay Alemseged of the Max Planck Institute for Evolutionary
Anthropology in Leipzig, Germany, named the fossil DIK 1-1 and nicknamed
it Dikika baby after the Dikika research site. The Dikika fossil

Format: Articles

Subject: Theories

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

John Hunter (1728–1793)

John Hunter studied human reproductive anatomy, and in eighteenth century England, performed one of the earliest described cases of artificial insemination. Hunter dissected thousands of animals and human cadavers to study the structures and functions of organ systems. Much of his anatomical studies focused on the circulatory, digestive, and reproductive systems. He helped to describe the exchange of blood between pregnant women and their fetuses. Hunter also housed various natural collections, as well as thousands of preserved specimens from greater than thirty years of anatomy work.

Format: Articles

Subject: People, Reproduction

China's One-Child Policy

In September 1979, China's Fifth National People's Congress passed a policy that encouraged one-child families. Following this decision from the Chinese Communist Party (CCP), campaigns were initiated to implement the One-Child Policy nationwide. This initiative constituted the most massive governmental attempt to control human fertility and reproduction in human history. These campaigns prioritized reproductive technologies for contraception, abortion, and sterilization in gynecological and obstetric medicine, while downplaying technologies related to fertility treatment.

Format: Articles

Subject: Ethics, Legal, Reproduction

Nightlight Christian Adoptions, et al. v. Thompson, et al. (2001)

Nightlight Christian Adoptions et al. v. Thompson et al. was a lawsuit filed in the United States District Court for the District of Columbia on 8 March 2001. The suit was filed because Nightlight Christian Adoptions, a frozen embryo adoption agency, felt that the Guidelines for Research Using Human Pluripotent Stem Cells published by the National Institutes for Health were unlawful and violated the restrictions on human embryo research put into place by the Dickey-Wicker Amendment. Additional plaintiffs with this suit were the Christian Medical Association, adult stem cell researcher Dr.

Format: Articles

Subject: Legal, Reproduction

"Genetic Programming: Artificial Nervous Systems, Artificial Embryos and Embryological Electronics" (1991), by Hugo de Garis

In 1991, Hugo de Garis' article "Genetic Programming: Artificial Nervous Systems, Artificial Embryos and Embryological Electronics" was published in the book Parallel Problem Solving from Nature. With this article de Garis hoped to create what he envisioned as a new branch of artificial embryology called embryonics (short term for "embryological electronics"). Embryonics is based on the idea of adapting the processes found in embryonic development to build artificial systems.

Format: Articles

Subject: Publications