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Edward Drinker Cope (1840-1897)

Edward Drinker Cope studied fossils and anatomy in the US in the late nineteenth century. Based on his observations of skeletal morphology, Cope developed a novel mechanism to explain the law of parallelism, the idea that developing organisms successively pass through stages resembling their ancestors. Others had proposed the addition of new body forms at the end of an individual organism's developed as a mechanism through which new species arose, but those proposals relied on changes in the lengths of gestation or incubation.

Format: Articles

Subject: People

Rita Levi-Montalcini (1909-2012)

Rita Levi-Montalcini is a Nobel Laureate recognized for her work in the discovery and characterization of nerve growth factor. Nerve growth factor (NGF) promotes the growth and maintenance of the nervous system in a developing system. The majority of her career has been devoted to investigating the many aspects of NGF.

Format: Articles

Subject: People

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

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

Pope Innocent XI (1611-1689)

Pope Innocent XI, born Benedetto Odescalchi, made considerable contributions to the Roman Catholic approach to embryology by condemning several propositions on liberal moral theology in 1679, including two related to abortion and ensoulment. His rejection of these principles strengthened the Church's stance against abortion and for the idea of "hominization," meaning the presence of human qualities before birth.

Format: Articles

Subject: People, Religion, Reproduction

St. Augustine (354-430)

St. Augustine of Hippo, born Aurelius Augustinus to a respectable family in the year 354 CE, is now considered one of the foremost theologians in the history of the Catholic Church. His writings, including his philosophy regarding life in the womb and the moral worth of embryos, influenced many other great thinkers of his time and throughout history.

Format: Articles

Subject: People, Religion

Christian Heinrich Pander (1794-1865)

Christian Heinrich Pander, often remembered as the father of embryology, also explored the fields of osteology, zoology, geology, and anatomy. He was born in Riga, Latvia, on 24 July 1794. Pander, with an eclectic history of research, is best remembered for his discovery and explanation of the structure of the chick blastoderm, a term he coined. In doing so, Pander was able to achieve the goal set forth by his teacher, Ignaz Döllinger, to reinvigorate the study of the chick embryo as a means of further exploring the science of embryology as a whole.

Format: Articles

Subject: People

William Harvey (1578-1657)

Renowned physician and scientist William Harvey is best known for his accurate description of how blood circulates through the body. While his published work on the circulation of blood is considered the most important of his academic life, Harvey also made significant contributions to embryology with the publication of his book Exercitationes de Generatione Animalium in 1651. In this book he established several theories that would set the stage for modern embryology and addressed many embryological issues including conception, embryogenesis, and spontaneous generation.

Format: Articles

Subject: People

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

Edward B. Lewis (1918-2004)

Edward B. Lewis studied embryonic development in Drosophila, including the discovery of the cis-trans test for recessive genes, and the identification of the bithorax complex and its role in development in Drosophila. He shared the 1995 Nobel Prize in Physiology or Medicine with Christiane Nüsslein-Volhard and Eric F. Wieschaus for work on genetic control of early embryonic development.

Format: Articles

Subject: People

Caspar Friedrich Wolff (1734-1794)

Caspar Friedrich Wolff is most famous for his 1759 doctoral dissertation, Theoria Generationis, in which he described embryonic development in both plants and animals as a process involving layers of cells, thereby refuting the accepted theory of preformation: the idea that organisms develop as a result of the unfolding of form that is somehow present from the outset, as in a homunculus. This work generated a great deal of controversy and discussion at the time of its publication but was an integral move in the reemergence and acceptance of the theory of epigenesis.

Format: Articles

Subject: People

Gavin Rylands de Beer (1899-1972)

Gavin de Beer was an English zoologist known for his contributions to evolution and embryology, in particular for showing the inadequacy of the germ layer theory as it was then proposed. He was born in London, England, on 1 November 1899, but was raised for his first thirteen years in France where his father worked for a telegraph company. He entered Magdalen College, Oxford, in 1917 but his studies were soon interrupted by World War I. After serving in the military, he returned to Oxford where he studied under Edwin Goodrich.

Format: Articles

Subject: People

Stanley Cohen (1922- )

Stanley Cohen is a biochemist who participated in the discovery of nerve growth factor (NGF) and epidermal growth factor (EGF). He shared the 1986 Nobel Prize in Physiology or Medicine with Rita Levi-Montalcini for their work on the discovery of growth factors. His work led to the discovery of many other growth factors and their roles in development.

Format: Articles

Subject: People

Libbie Henrietta Hyman (1888-1969)

Libbie Henrietta Hyman was born into a recently immigrated Jewish family on 6 December 1888 in Des Moines, Iowa. One of many siblings and daughter to parents Sabina Neumann and Joseph Hyman, who did not particularly support her interests in science, Hyman excelled in school and indulged her interests in biology in her free time. From a young age, Hyman collected and cataloged flora around her home. Despite being valedictorian of her high school class, Hyman's first job was labeling cereal boxes in a local factory.

Format: Articles

Subject: People

Antoni van Leeuwenhoek (1632-1723)

Antoni van Leeuwenhoek was born in Delft, the Netherlands, on 24 October 1632 to Margriet Jacobsdochter van den Berch and Philips Thooniszoon, both of whom were middle-class artisans. He attended grammar school in Warmond, and then temporarily moved to Benthuizen to live with relatives. Eventually Leeuwenhoek left for Amsterdam to work as a cloth merchant's apprentice. Returning to Delft, he married Barbara de Mey on 29 July 1654, and worked as a shopkeeper. The marriage resulted in five children, only one of whom, Maria, outlived Leeuwenhoek.

Format: Articles

Subject: People

Hilde Mangold (1898-1924)

Hilde Mangold, previously Hilde Proescholdt, was a German embryologist and physiologist who became well known for research completed with Hans Spemann in the 1920s. As a graduate student, Mangold assisted Spemann and together they discovered and coined the term the "organizer." The organizer discovery was a crucial contribution to embryology that led to further understanding of the pattern of embryo differentiation of amphibians.

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

Marcello Malpighi (1646-1694)

Marcello Malpighi studied chick embryos with microscopes in Italy during the seventeenth century. Trained as a medical doctor, he was among the first scientists to use the microscope to examine embryos at very early stages. Malpighi described early structures in chick embryos, and later scientists used his descriptions to help develop the theory of preformationism.

Format: Articles

Subject: People

Johann Gregor Mendel (1822-1884)

Johann Gregor Mendel studied plants and their patterns of inheritance in Austria during the nineteenth century. Mendel experimented with the pea plant, Pisum, and his publication, 'Versuche uber Pflanzenhybriden' (“Experiments on Plant Hybridization”), published in 1866, revolutionized theories of trait inheritance. Mendel’s discoveries relating to factors, traits, and how they pass between generations of organisms enabled scientists in the twentieth century to build theories of genetics.

Format: Articles

Subject: People

Solomon A. Berson (1918-1972)

Solomon A. Berson helped develop the radioimmunoassay (RIA) technique in the US during the twentieth century. Berson made many scientific contributions while working with research partner Rosalyn Yalow at the Bronx Veterans Administration (VA) hospital, in New York City, New York. In the more than twenty years that Berson and Yalow collaborated, they refined the procedures for tracing diagnostic biological compounds using isotope labels.

Format: Articles

Subject: People

Walter Stanborough Sutton (1877-1916)

Walter Stanborough Sutton studied grasshoppers and connected the phenomena of meiosis, segregation, and independent assortment with the chromosomal theory of inheritance in the early twentieth century in the US. Sutton researched chromosomes, then called inheritance mechanisms. He confirmed a theory of Wilhelm Roux, who studied embryos in Breslau, Germany, in the late 1880s, who had argued that chromosomes and heredity were linked. Theodor Boveri, working in Munich, Germany, independently reached similar conclusions about heredity as Sutton.

Format: Articles

Subject: People

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

George Wells Beadle (1903-1989)

George Wells Beadle studied corn, fruit flies, and funguses in the US during the twentieth century. These studies helped Beadle earn the 1958 Nobel Prize in Physiology or Medicine. Beadle shared the prize with Edward Tatum for their discovery that genes help regulate chemical processes in and between cells. This finding, initially termed the one gene-one enzyme hypothesis, helped scientists develop new techniques to study genes and DNA as molecules, not just as units of heredity between generations of organisms.

Format: Articles

Subject: People

Wilhelm Friedrich Phillip Pfeffer (1845-1920)

Wilhelm Friedrich Phillip Pfeffer studied plants in Germany during the late nineteenth and early twentieth centuries. He started his career as an apothecary, but Pfeffer also studied plant physiology, including how plants move and react to changes in light, temperature, and osmotic pressure. He created the Pfeffer Zelle apparatus, also known as the Pfeffer Cell, to study osmosis in plants. PfefferÕs experiments led to new theories about the structure and development of plants.

Format: Articles

Subject: People

Dennis Lo (1963- )

Dennis Lo, also called Yuk Ming Dennis Lo, is a
professor at the Chinese University of Hong Kong in Hong Kong,
China. In 1997, Lo discovered fetal DNA in maternal
plasma, which is the liquid component of a pregnant woman's
blood. By 2002, Lo distinguished the DNA differences between pregnant women
and their fetuses, enabling scientists to identify fetal DNA in pregnant
women's blood. Lo used his discoveries to develop several
non-invasive and prenatal genetic tests, including tests for blood

Format: Articles

Subject: People, Reproduction