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Roman Catholic Church Quickening

Although the concept of quickening was not developed initially by the Roman Catholic Church, much of their histories are intertwined. Quickening, the point at which a pregnant woman can first feel the movements of the growing embryo or fetus, has long been a pivotal moment in pregnancy. Historically, it has also been a pivotal moment for law and the Church in deciding the criminal and religious sanctions for women who intentionally procured an abortion.

Format: Articles

Subject: Religion

Birth without Violence (1975), by Frederick Leboyer

In Birth without Violence (1975), French obstetrician Frederick Leboyer describes in poetic form the possible perceptions and feelings of embryos and fetuses before, during, and after birth. His work has helped to promote a gentler and more sensitive birthing method with the goal of easing the newborn's transition from the womb to the outside world. Leboyer's birthing method influenced later birth techniques such as water birth and unassisted childbirth.

Format: Articles

Subject: Publications, Reproduction

Edward Drinker Cope's Law of Acceleration of Growth

The Law of Acceleration of Growth is a theory proposed by Edward Drinker Cope in the US during the nineteenth century. Cope developed it in an attempt to explain the evolution of genera by appealing to changes in the developmental timelines of organisms. Cope proposed this law as an additional theory to natural selection.

Format: Articles

Subject: Theories

Aristotle (384-322 BCE)

Aristotle studied developing organisms, among other things, in ancient Greece, and his writings shaped Western philosophy and natural science for greater than two thousand years. He spent much of his life in Greece and studied with Plato at Plato's Academy in Athens, where he later established his own school called the Lyceum. Aristotle wrote greater than 150 treatises on subjects ranging from aesthetics, politics, ethics, and natural philosophy, which include physics and biology. Less than fifty of Aristotle's treatises persisted into the twenty-first century.

Format: Articles

Subject: People

Corpus Callosum Defects Associated with Fetal Alcohol Syndrome

Prenatal exposure to alcohol (ethanol) can result in a continuum of developmental abnormalities that are highly variable depending on the severity, duration, frequency, and timing of exposure during gestation. Defects of the corpus callosum (CC) have proven to be a reliable indicator of prenatal alcohol exposure as it affects the brain. Structural abnormalities of the CC occur along a continuum, like most alcohol-induced anomalies, whereby more severe prenatal exposure results in a greater expression of the abnormal trait.

Format: Articles

Subject: Disorders, Reproduction

Some of the Cells that Arise from Animal Gastrulas with Three Germ Layers

Object is a digital image of an animal triploblastic gastrula. The image labels the three germ layers and some of the fully differentiated cell types that arise from those germ layers. The image shows the egg and sperm germ cells. It also shows and labels the epithelial cells, liver cells, and endothelial cells that develop from endoderm. It also shows the skeletal musclecells, osteoblast cells, cardiac muscle cells, and red blood cells that develop from the mesoderm. It also shows the hair cells, skin cells, and neuron cells that develop from the ectoderm.

From a developing embryos three primary germ layers, ectoderm (green), mesoderm (pink) and endoderm (yellow), a variety of differentiated cell types and organ systems arise, far more than are shown here. The three primary germ layers are shown during the gastrula stage because they become distinct at the gastrula stage. The germ cells (blue) are pre- cursors to sperm and egg cells, and they are set aside early in development, and are thought to arise from the ectoderm.

Format: Graphics

Samuel Randall Detwiler (1890-1957)

Samuel Randall Detwiler was an embryologist who studied neural development in embryos and vertebrate retinas. He discovered evidence for the relationship between somites and spinal ganglia, that transplanted limbs can be controlled by foreign ganglia, and the plasticity of ganglia in response to limb transplantations. He also extensively studied vertebrate retinas during and after embryonic development.

Format: Articles

Subject: People

Agent Orange as a Cause of Spina Bifida

Spina bifida is a birth defect that affects the spines of developing fetuses and infants, and research in the 20th century indicated that chemicals in the herbicide Agent Orange likely lead to the birth defect. People with spina bifida can have nerve damage, paralysis, and mental disabilities. During the Vietnam War in the 1960s, the US military employed Agent Orange and other herbicides to destroy enemy crops and forest cover until 1970.

Format: Articles

Subject: Disorders

"Experiments on Embryonic Induction III. A Note on Inductions by Chick Primitive Streak Transplanted to the Rabbit Embryo" (1934), by Conrad Hal Waddington

Conrad Hal Waddington's "Experiments on Embryonic Induction III," published in 1934 in the Journal of Experimental Biology, describes the discovery that the primitive streak induces the mammalian embryo. Waddington's hypothesis was that a transplanted primitive streak could induce neural tissue in the ectoderm of the rabbit embryo. The primitive streak defines the axis of an embryo and is capable of inducing the differentiation of various tissues in a developing embryo during gastrulation.

Format: Articles

Subject: Experiments

Viktor Hamburger (1900-2001)

Viktor Hamburger was an embryologist who focused on neural development. His scientific career stretched from the early 1920s as a student of Hans Spemann to the late 1980s at Washington University resolving the role of nerve growth factor in the life of neurons. Hamburger is noted for his systematic approach to science and a strict attention to detail. Throughout his life he maintained an interest in nature and the arts, believing both were important to his scientific work.

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 e-Mouse Atlas Project (1992- )

The Edinburgh Mouse Atlas, also called the e-Mouse Atlas Project (EMAP), is an online resource comprised of the e-Mouse Atlas (EMA), a detailed digital model of mouse development, and the e-Mouse Atlas of Gene Expression (EMAGE), a database that identifies sites of gene expression in mouse embryos. Duncan Davidson and Richard Baldock founded the project in 1992, and the Medical Research Council (MRC) in Edinburgh, United Kingdom, funds the project.

Format: Articles

Subject: Technologies

Hox Genes and the Evolution of Vertebrate Axial Morphology Experiment (1995)

In 1995, researchers Ann Burke, Craig Nelson, Bruce Morgan, and Cliff Tabin in the US studied the genes that regulate the construction of vertebra in developing chick and mouse embryos, they showed similar patterns of gene regulation across both species, and they concluded that those patterns were inherited from an ancestor common to all vertebrate animals. The group analyzed the head-to-tail (anterior-posterior) axial development of vertebrates, as the anterior-posterior axis showed variation between species over the course of evolutionary time.

Format: Articles

Subject: Experiments

Neurospora crassa Life Cycle

Object is a digital image with two parts that together show the Neurospora life cycle. The left part shows the asexual reproductive cycle of the mold. The right part shows the sexual reproductive cycle of the mold.

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

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

Amniocentesis

Amniocentesis is a test used for prenatal diagnosis of inherited diseases, Rh incompatibility, neural tube defects, and lung maturity. Normally performed during the second trimester of a pregnancy, this invasive procedure allows the detection of health problems in the fetus as early as fifteen weeks gestation. Although amniocentesis does carry some significant risks, the medical community commonly accepts it as a safe and useful procedure.

Format: Articles

Subject: Technologies, Reproduction

"Proliferation, Differentiation and Degeneration in the Spinal Ganglia of the Chick Embryo under Normal and Experimental Conditions" (1949), by Viktor Hamburger and Rita Levi-Montalcini

In this paper Viktor Hamburger and Rita Levi-Montalcini collaborated to examine the effects of limb transplantation and explantation on neural development. In 1947 Hamburger invited Levi-Montalcini to his lab at Washington University in St. Louis to examine this question. Independently, each had previously arrived at opposing conclusions based on the same data.

Format: Articles

Subject: Experiments

Hensen's Node

A node, or primitive knot, is an enlarged group of cells located in the anterior portion of the primitive streak in a developing gastrula. The node is the site where gastrulation, the formation of the three germ layers, first begins. The node determines and patterns the anterior-posterior axis of the embryo by directing the development of the chordamesoderm. The chordamesoderm is a specific type of mesoderm that will differentiate into the notochord, somites, and neural tube. Those structures will later form the vertebral column.

Format: Articles

Subject: Processes

Ectoderm

Ectoderm is one of three germ layers--groups of cells that coalesce early during the embryonic life of all animals except maybe sponges, and from which organs and tissues form. As an embryo develops, a single fertilized cell progresses through multiple rounds of cell division. Eventually, the clump of cells goes through a stage called gastrulation, during which the embryo reorganizes itself into the three germ layers: endoderm, ectoderm, and mesoderm. After gastrulation, the embryo goes through a process called neurulation, which starts the development of nervous system.

Format: Articles

Subject: Processes

The Miracle of Life (1983), by NOVA

The most-watched NOVA documentary ever made and a revolution in the understanding of human development, The Miracle of Life (abbreviated Life) employs the most current developments in endoscopic and microscopic technology to capture the intricacies of human development. Narrated by Anita Sangiolo and vividly illustrating the most minute and hard-to-reach parts and processes of living systems, this film truly flexes the muscles of the newest photographic technology of its time, with esteemed photographer Lennart Nilsson behind the camera.

Format: Articles

Subject: Outreach, Reproduction

"The Multi-Dimensional Human Embryo"

The Multi-Dimensional Human Embryo website (http://embryo.soad.umich.edu/) is a publicly accessible online database of the first three-dimensional images and animations of human embryos during different stages of development. Both the images and animations were created using magnetic resonance microscopy and compiled for easy access.

Format: Articles

Subject: Outreach, Organizations

Diprosopus (Craniofacial Duplication)

Diprosopus is a congenital defect also known as craniofacial duplication. The exact description of diprosopus refers to a fetus with a single trunk, normal limbs, and facial features that are duplicated to a certain degree. A less severe instance is when the nose is duplicated and the eyes are spaced far apart. In the most extreme instances, the entire face is duplicated, hence the name diprosopus, which is Greek for two-faced. Fetuses with diprosopus often also lack brains (anencephaly), have neural tube defects, or heart malformations.

Format: Articles

Subject: Disorders, Reproduction

“The Emergence of Developmental Psychopathology” (1984), by Dante Cicchetti

In 1984, Dante Cicchetti published “The Emergence of Developmental Psychopathology,” an article in which he argued that the previously amorphous study of developmental psychopathology was emerging as a unified discipline. According to Cicchetti, developmental psychopathology describes an interdisciplinary field that studies abnormalities in psychological function that can arise during human development.

Format: Articles

Subject: Publications

The Formation of Reticular Theory

In the nineteenth century, reticular theory aimed to describe the properties of neurons, the specialized cells which make up the nervous system, but was later disconfirmed by evidence. Reticular theory stated that the nervous system was composed of a continuous network of specialized cells without gaps (synapses), and was first proposed by researcher Joseph von Gerlach in Germany in 1871.

Format: Articles

Subject: Theories

Beadle and Ephrussi’s Technique to Transplant Optic Discs between Fruit Fly Larvae

Object is a digital image of fruit fly larvae. There are three panes. In the first, a micropipette sucks the optic disc from a fruit fly larva. In the second, the micropipette pushes the optic disc into the abdomen of another fruit fly larva. The third pane shows the adult fruit fly from the second pane with an eye that has developed in its abdomen.

In 1935, George Beadle and Boris Ephrussi developed a technique to transplant optic discs between fruit fly larvae. They developed it while at the California Institute of Technology in Pasedena, California. Optic discs are tissues from which the adult eyes develop. Beadle and Ephrussi used their technique to study the development of the eye and eye pigment. (1) The experimenter dissects a donor larva, which is in the third instar stage of development, and removes the optic disc (colored red) with a micropipette.

Format: Graphics

Subject: Technologies, Experiments, Organisms