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Wilhelm His, Sr. (1831-1904)

Wilhelm His, Sr. was born on 9 July 1831 in Basel, Switzerland, to Katharina La Roche and Eduard His. He began his medical studies at Basel in 1849 and later transferred to the University of Bern during the winter semester of 1849-1850. A year later, His arrived at the University of Berlin, where he studied under Johannes Müller and Robert Remak. For his clinical training, His attended the University of Würzburg from 1852-1853.

Format: Articles

Subject: People

Golgi Staining Technique

The Golgi staining technique, also called the black reaction after the stain's color, was developed in the 1870s and 1880s in Italy to make brain cells (neurons) visible under the microscope. Camillo Golgi developed the technique while working with nervous tissue, which required Golgi to examine cell structure under the microscope. Golgi improved upon existing methods of staining, enabling scientists to view entire neurons for the first time and changing the way people discussed the development and composition of the brain's cells.

Format: Articles

Subject: Technologies, Processes

John von Neumann (1903-1957)

John von Neumann was a Hungarian mathematician who made important contributions to mathematics, physics, computer science, and the area of artificial life. He was born in Budapest, Hungary, on 28 December 1903. His mother was Margit von Neumann and his father was Max von Neumann. His work on artificial life focused on the problem of the self-reproduction of machines. Von Neumann initially discussed self-reproducing machines in his Hixon Symposium paper "The General and Logical Theory of Automata" published in 1948.

Format: Articles

Subject: People

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

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

Mesoderm

Mesoderm is one of the three germ layers, groups of cells that interact early during the embryonic life of animals and from which organs and tissues form. As organs form, a process called organogenesis, mesoderm interacts with endoderm and ectoderm to give rise to the digestive tract, the heart and skeletal muscles, red blood cells, and the tubules of the kidneys, as well as a type of connective tissue called mesenchyme. All animals that have only one plane of symmetry through the body, called bilateral symmetry, form three germ layers.

Format: Articles

Subject: Processes

The Origin of Species: "Chapter Thirteen: Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs" (1859), by Charles R. Darwin

Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs is the thirteenth chapter of Charles Darwin's book The Origin of Species, first published in England in 1859. The book details part of Darwin's argument for the common ancestry of life and natural selection as the cause of speciation. In this chapter, Darwin summarizes the evidence for evolution by connecting observations of development in organisms to the processes of natural selection.

Format: Articles

Subject: Publications

Albert William Liley (1929-1983)

Albert William Liley advanced the science of fetal physiology and the techniques of life-saving in utero blood transfusions for fetuses with Rh incompatibility, also known as hemolytic disease. Due to his advances, fetuses too young to survive premature delivery, and likely to die in utero if their Rh incompabilities were left untreated, were successfully transfused and carried to term. Liley was as passionate as a clinician and researcher as he was about his views on the rights of the unborn.

Format: Articles

Subject: People, 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

Karl Ernst von Baer's Laws of Embryology

In 1828, while working at the University of Konigsberg in Konigsberg, Germany Karl Ernst von Baer proposed four laws of animal development, which came to be called von Baer's laws of embryology. With these laws, von Baer described the development (ontogeny) of animal embryos while also critiquing popular theories of animal development at the time.

Format: Articles

Subject: Theories

"The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme" (1979), by Stephen J. Gould and Richard C. Lewontin

The Spandrels of San Marco and the Panglossian Paradigm:
A Critique of the Adaptationist Programme, hereafter called
The Spandrels, is an article written by Stephen J. Gould and
Richard C. Lewontin published in the Proceedings of the Royal
Society of London in 1979. The paper emphasizes issues with
what the two authors call adaptationism or the adaptationist
programme as a framework to explain how species and traits evolved. The paper
is one in a series of works in which Gould emphasized the

Format: Articles

Subject: Publications, Theories

Gunther von Hagens (1945- )

Gunther von Hagens invented a plastination technique and created Body Worlds, a traveling exhibit that has made anatomy part of the public domain. Von Hagens invented the plastination technique in 1977 while working at Heidelberg University in Heidelberg, Germany. Von Hagen's plastination technique preserves real bodies and tissues by the removal of the fluid and replacement with resin. Body Worlds features three-dimensional, plastinated human bodies.

Format: Articles

Subject: People, Outreach, Reproduction

Albrecht von Haller (1708-1777)

Victor Albrecht von Haller was an 18th century scientist who did extensive work in the life sciences, including anatomy and physiology, botany, and developmental biology. His embryological work consisted of experiments in understanding the process of generation, and led him to adopt the model of preformationism called ovism (the idea that the new individual exists within the maternal egg prior to conception). Haller was born in Bern, Switzerland, on 16 October, 1708. His mother was Anna Maria Engel, and his father was Niklaus Emanuel Haller.

Format: Articles

Subject: People

Julius von Sachs (1832-1897)

Julius von Sachs helped establish plant physiology through his experiments in latter nineteenth-century Germany. Sachs infused the inchoate discipline of plant physiology with experimental techniques and a mechanistic stance, both of which cemented his place as one of the discipline s founders. Sachs trained a generation of plant physiologists, and his stress on experimentation and mechanism influenced biologists in other disciplines, especially embryologist Jacques Loeb.

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

Karl Ernst von Baer (1792-1876)

Best known for his contributions to the field of embryology, Karl Ernst von Baer also pursued a variety of other areas of study including medicine, botany, zoology, and anthropology. Committing his life to scientific research, von Baer's work led to the advancement of the understanding of mammalian reproduction, development, and organ functioning. His embryological discoveries ultimately led him to a view of development that supported epigenesis and refuted long-held thinking about preformation.

Format: Articles

Subject: People

John von Neumann's Cellular Automata

Cellular automata (CA) are mathematical models used to simulate complex systems or processes. In several fields, including biology, physics, and chemistry, CA are employed to analyze phenomena such as the growth of plants, DNA evolution, and embryogenesis. In the 1940s John von Neumann formalized the idea of cellular automata in order to create a theoretical model for a self-reproducing machine. Von Neumann's work was motivated by his attempt to understand biological evolution and self-reproduction.

Format: Articles

Subject: Theories

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

Karl Wilhelm Theodor Richard von Hertwig (1850-1937)

Karl Wilhelm Theodor Richard von Hertwig is an important figure in the history of embryology for his contributions of artificial hybridization of sea urchin eggs and the formulation of his coelom theory. He was born 23 September 1850 in Friedelberg, Germany, to Elise Trapp and Carl Hertwig. Richard and his older brother Oscar began their studies at Jena under the direction of Ernst Haeckel from 1868 to 1871. In 1872 Hertwig became a lecturer in zoology at Jena while Oscar lectured in anatomy and embryology.

Format: Articles

Subject: People

Julia Barlow Platt's Embryological Observations on Salamanders' Cartilage (1893)

In 1893, Julia Barlow Platt published her research on the origins of cartilage in the developing head of the common mudpuppy (Necturus maculosus) embryo. The mudpuppy is an aquatic salamander commonly used by embryologists because its large embryonic cells and nuclei are easy to see. Platt followed the paths of cells in developing mudpuppy embryos to see how embryonic cells migrated during the formation of the head. With her research, Platt challenged then current theories about germ layers, the types of cells in an early embryo that develop into adult cells.

Format: Articles

Subject: Experiments, Theories, Processes

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