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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

Essay: Homology

Homology is a central concept of comparative and evolutionary biology, referring to the presence of the same bodily parts (e.g., morphological structures) in different species. The existence of homologies is explained by common ancestry, and according to modern definitions of homology, two structures in different species are homologous if they are derived from the same structure in the common ancestor.

Format: Essays and Theses

Subject: Processes

Stanley Alan Plotkin (1932– )

Stanley Alan Plotkin developed vaccines in the United States during the mid to late twentieth century. Plotkin began his research career at the Wistar Institute in Philadelphia, Pennsylvania, where he studied the rubella virus. In pregnant women, the rubella virus caused congenital rubella syndrome in the fetus, which led to various malformations and birth defects. Using WI-38 cells, a line of cells that originated from tissues of aborted fetuses, Plotkin successfully created RA27/3, a weakened strain of the rubella virus, which he then used to develop a rubella vaccine.

Format: Articles

Subject: People

Neonatal Jaundice

Neonatal jaundice is the yellow discoloration of the skin and eyes due to elevated bilirubin levels in the bloodstream of a newborn. Bilirubin is a byproduct of the breakdown of red blood cells. Jaundiced infants are unable to process bilirubin at a normal rate or they have an abnormally high amount of bilirubin in their bloodstream, resulting in a buildup of the yellow colored bilirubin. That build up is called hyperbilirubinemia and is the cause of jaundice.

Format: Articles

Subject: Disorders

William Withey Gull (1816-1890)

William Withey Gull studied paraplegia, anorexia, and hormones as a physician in England during the nineteenth century. In addition to caring for patients, he described the role of the posterior column of the spinal cord in paraplegia, and he was among the first to describe the conditions of anorexia and of hypochondria. He also researched the effects of thyroid hormone deficiencies in women who had malfunctioning thyroid glands.

Format: Articles

Subject: People

Richard Woltereck (1877-1944)

Richard Woltereck was a German zoologist and hydrobiologist who studied aquatic animals and extended the concept of Reaktionsnorm (norm of reaction) to the study of genetics. He also provided some of the first experimental evidence for the early twentieth-century embryological theory of heredity known as cytoplasmic inheritance. Through experiments on the water flea, Daphnia, Woltereck investigated whether variation produced by environmental impacts on development could play a role in heredity and evolution.

Format: Articles

Subject: People

Fetal Surgery

Fetal surgeries are a range of medical interventions performed in utero on the developing fetus of a pregnant woman to treat a number of congenital abnormalities. The first documented fetal surgical procedure occurred in 1963 in Auckland, New Zealand when A. William Liley treated fetal hemolytic anemia, or Rh disease, with a blood transfusion.

Format: Articles

Subject: Disorders, Ethics, Reproduction

The Role of the Notch signaling pathway in Somitogenesis

Among other functions, the Notch signaling pathway contributes to the development of somites in animals. It involves a cell signaling mechanism with a wide range of functions, including cellular differentiation, and the formation of the embryonic structures (embryogenesis). All multicellular animals use Notch signaling, which is involved in the development, maintenance, and regeneration of a range of tissues. The Notch signaling pathways spans two cells, and consists of receptor proteins, which cross one cell's membrane and interacts with proteins on adjacent cells, called ligands.

Format: Articles

Subject: Theories, Processes

Mitochondria

All cells that have a nucleus, including plant, animal, fungal cells, and most single-celled protists, also have mitochondria. Mitochondria are particles called organelles found outside the nucleus in a cell's cytoplasm. The main function of mitochondria is to supply energy to the cell, and therefore to the organism. The theory for how mitochondria evolved, proposed by Lynn Margulis in the twentieth century, is that they were once free-living organisms.

Format: Articles

Subject: Organisms, Theories

Barbara McClintock (1902-1992)

Barbara McClintock worked on genetics in corn (maize) plants and spent most of her life conducting research at the Cold Spring Harbor Laboratory in Laurel Hollow, New York. McClintock's research focused on reproduction and mutations in maize, and described the phenomenon of genetic crossover in chromosomes. Through her maize mutation experiments, McClintock observed transposons, or mobile elements of genes within the chromosome, which jump around the genome. McClintock received the Nobel Prize for Physiology or Medicine in 1983 for her research on chromosome transposition.

Format: Articles

Subject: People

Ilya Ilyich Mechnikov (Elie Metchnikoff) (1845-1916)

Ilya Ilyich Mechnikov studied phagocytes, immune function, and starfish embryos in Europe during the late nineteenth and early twentieth centuries. Mechnikov adopted the French form of his name, Élie Metchnikoff, in the last twenty-five years of his life. In 1908, he won the Nobel Prize in Physiology or Medicine with Paul Ehrlich for their contributions to immunology. Mechnikov discovered phagocytes, immune cells that protect organisms by ingesting foreign particles or microorganisms, by conducting experiments on starfish larvae.

Format: Articles

Subject: People

Christiane Nusslein-Volhard (1942- )

Christiane Nusslein-Volhard studied how genes control embryonic development in flies and in fish in Europe during the twentieth and twenty-first centuries. In the 1970s, Nusslein-Volhard focused her career on studying the genetic control of development in the fruit fly Drosophila melanogaster. In 1988, Nusslein-Volhard identified the first described morphogen, a protein coded by the gene bicoid in flies. In 1995, along with Eric F. Wieschaus and Edward B.

Format: Articles

Subject: People

Experimental Studies on Germinal Localization (1904), by Edmund B. Wilson

At the turn of the twentieth century, Edmund B. Wilson
performed experiments to show where germinal
matter was located in molluscs. At Columbia University in New York City,
New York, Wilson studied what causes cells to differentiate during
development. In 1904 he conducted his experiments on molluscs, and he modified the
theory about the location of germinal matter in the succeeding years. Wilson and others modified the
theory of germinal localization to accommodate results that showed

Format: Articles

Subject: Experiments

"A molecular wound response program associated with regeneration initiation in planarians" (2012), by Danielle Wenemoser et al.

In 2012, a team of scientists across the US conducted an experiment to find the mechanism that allowed a group of flatworms, planarians, to regenerate any body part. The group included Danielle Wenemoser, Sylvain Lapan, Alex Wilkinson, George Bell, and Peter Reddien. They aimed to identify genes that are expressed by planarians in response to wounds that initiated a regenerative mechanism. The researchers determined several genes as important for tissue regeneration.

Format: Articles

Subject: Experiments

“Sex Limited Inheritance in Drosophila” (1910), by Thomas Hunt Morgan

In 1910, Thomas Hunt Morgan performed an experiment at Columbia University, in New York City, New York, that helped identify the role chromosomes play in heredity. That year, Morgan was breeding Drosophila, or fruit flies. After observing thousands of fruit fly offspring with red eyes, he obtained one that had white eyes. Morgan began breeding the white-eyed mutant fly and found that in one generation of flies, the trait was only present in males.

Format: Articles

Subject: Experiments, Publications

Ziegler Wax Embryo Models

Three-dimensional anatomical models have long been essential to the learning of science and lend a sense of "control" to those practicing in the field. As the development of embryology grew in importance during the late 1800s, so did the need for models to show intricate details of embryos.

Format: Articles

Subject: Technologies, Reproduction

Cord Blood Banking

Cord blood banks are institutions designed to store umbilical cord blood (UCB) stem cells. UCB, a source of hematopoietic stem cells (HSCs), has garnered attention from scientific and medical communities since its first successful use in a hematopoietic stem cell transplant (HSCT) in 1988. The umbilical cord is the lifeline by which the growing fetus is nourished by the mother. Once regarded as medical waste, the umbilical cord has become a source of lifesaving treatment.

Format: Articles

Subject: Technologies, Reproduction

Charles Bonnet (1720-1793)

Charles Bonnet was a naturalist and philosopher in the mid eighteenth century. His most important contribution to embryology was the discovery of parthenogenesis in aphids, proving that asexual reproduction of offspring was possible. In his later life, he was an outspoken defender of the theory of generation now known as preformationism, which stated that offspring exist prior to conception preformed in the germ cell of one of their parents.

Format: Articles

Subject: People

Advanced Cell Technology, Inc.

Advanced Cell Technology, Inc. (ACT) is a biotechnology company that uses stem cell technology to develop novel therapies in the field of regenerative medicine. Formed in 1994, ACT grew from a small agricultural cloning research facility located in Worcester, Massachusetts, into a multi-locational corporation involved in using both human embryonic stem cells (hESC) and human adult stem cells as well as animal cells for therapeutic innovations.

Format: Articles

Subject: Organizations, Reproduction

Pre- and Post-natal Growth Deficiencies and Fetal Alcohol Syndrome

Maternal consumption of alcohol (ethanol) during pregnancy can inhibit prenatal growth, resulting in fetuses that are small for gestational age. Those prenatal growth deficiencies can have lasting consequences for early childhood development and are often reflected by low weight and stature. Those alcohol-induced pre- and post-natal growth deficiencies ("failure to thrive") are among the abnormal developmental criteria used to identify Fetal Alcohol Syndrome (FAS). FAS is characterized by minor facial abnormalities and deficiencies of the central nervous system as well.

Format: Articles

Subject: Disorders

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

Form and Function (1916), by Edward Stuart Russell

In 1916, at the age of twenty-nine, Edward Stuart Russell published his first major work, Form and Function: a Contribution to the History of Animal Morphology. This book has maintained wide readership among scientists and historians since its initial publication, and today is generally recognized as the first modern, sustained study of the history of morphology. In particular, Form and Function incorporates an extensive theoretical analysis of the relationship between embryological studies and comparative morphology in the nineteenth century.

Format: Articles

Subject: Publications

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

Uniform Anatomical Gift Act (1968)

The Uniform Anatomical Gift Act (UAGA or the Act) was passed in the US in 1968 and has since been revised in 1987 and in 2006. The Act sets a regulatory framework for the donation of organs, tissues, and other human body parts in the US. The UAGA helps regulate body donations to science, medicine, and education. The Act has been consulted in discussions about abortion , fetal tissue transplants , and Body Worlds , an anatomy exhibition.

Format: Articles

Subject: Legal, Outreach, Reproduction

Franz Julius Keibel (1861-1929)

Franz Keibel studied the embryos of humans and other animals in Europe at the turn of the twentieth century. He lived and worked in several different parts of Germany and France. Keibel drew illustrations of embryos in many stages of development. Keibel used these illustrations, which he and others in the scientific community called normal plates, to describe the development of organisms in several species of vertebrates.

Format: Articles

Subject: People