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Pope John Paul II (1920-2005)

Pope John Paul II's views on abortion and embryology have been very influential to the Roman Catholic Church. He strictly forbade abortion and other threats to what he regarded as early human life in his encyclical entitled "Evangelium Vitae," meaning the "Gospel of Life." His authority on moral and social issues was highly regarded during his lifetime.

Format: Articles

Subject: People, Religion, Reproduction

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

John Chassar Moir (1900–1977)

John Chassar Moir lived in Scotland during the twentieth century and helped develop techniques to improve the health of pregnant women. Moir helped to discover compounds that doctors could administer to women after childbirth to prevent life-threatening blood loss. Those compounds included the ergot alkaloid called ergometrine, also called ergonovine, and d-lysergic acid beta-propanolamide. Moir tested ergometrine in postpartum patients and documented that it helped prevent or manage postpartum hemorrhage in women.

Format: Articles

Subject: People, Reproduction, Disorders

John George Children (1777–1852)

John George Children described several species of insects and animals while working at the British Museum in London, England, in the eighteenth and nineteenth centuries. Children also conducted research on chemical batteries called voltaic cells and briefly studied and manufactured gunpowder. One of the species he described, the Children’s python, or Antaresia children, was used in the twenty-first century as the subject of experiments that involved the biological cost of reproduction in snakes.

Format: Articles

Subject: People

Ernest John Christopher Polge (1926-2006)

Twentieth-century researcher Ernest John Christopher Polge studied the reproductive processes of livestock and determined a method to successfully freeze, thaw, and utilize viable sperm cells to produce offspring in animals. In 1949, Polge identified glycerol as a cryoprotectant, or a medium that enables cells to freeze without damaging their cellular components or functions. Several years later, Polge used glycerol in a freezing process called vitrification, which enabled him to freeze poultry sperm, thaw that sperm, and use it to fertilize vertebrate embryos.

Format: Articles

Subject: People

Morphogenesis: An Essay on Development (1952), by John Tyler Bonner

Throughout his long and fruitful career John Tyler Bonner has made great strides in understanding basic issues of embryology and developmental-evolutionary biology. Indeed, Bonner's work on morphogenesis highlighted synergies between development and evolution long before "evo-devo" became a part of the scientific lingua franca. Princeton University Press published his first book, Morphogenesis: An Essay on Development, in 1952. In his autobiography Lives of a Biologist, Bonner described his motivations for writing Morphogenesis as a book about developmental biology.

Format: Articles

Subject: Publications

The Time Has Come: A Catholic Doctor's Proposals to End the Battle over Birth Control (1963), by John Rock

In 1963, Roman Catholic fertility doctor John Rock published The Time Has Come: A Catholic Doctor's Proposals to End the Battle over Birth Control, a first-person treatise on the use of scientifically approved forms of birth control for Catholic couples. The first contraceptive pill, called Enovid, had been on the market since June 1960, and Rock was one of the leading researchers in its development. In The Time Has Come, Rock explicitly describes the arguments for and against the use of birth control from both a religious and a scientific perspective.

Format: Articles

Subject: Publications, Religion, Reproduction

Slime Mold Video

This video is composed of a sequence of films created by John Tyler Bonner in the 1940s to show the life cycle of the cellular slime mold Dictyostelium discoideum. As only the second person to study slime molds, Bonner frequently encountered audiences who had never heard of, let alone seen, the unusual organism.

Format: Articles

Subject: Processes

Dictyostelium discoideum

Dictyostelium discoideum is a cellular slime mold that serves as an important model organism in a variety of fields. Cellular slime molds have an unusual life cycle. They exist as separate amoebae, but after consuming all the bacteria in their area they proceed to stream together to form a multicellular organism. These features make it a valuable tool for studying developmental processes and also for investigating the evolution of multicellularity. Long thought to be a type of fungus, it has recently been shown that slime molds in fact bear no relation to fungi.

Format: Articles

Subject: Organisms

Evangelium Vitae (1995), by Pope John Paul II

The encyclical entitled "Evangelium Vitae," meaning "The Gospel of Life," was promulgated on 25 March 1995 by Pope John Paul II in Rome, Italy. The document was written to reiterate the view of the Roman Catholic Church on the value of life and to warn against violating the sanctity of life. The document focuses on right to life issues including abortion, birth control, and euthanasia, but also touches on other concepts relevant to embryology, such as contraception, in vitro fertilization, sterilization, embryonic stem cell research, and fetal experimentation.

Format: Articles

Subject: Religion, Reproduction

"Developmental Capacity of Nuclei Transplanted from Keratinized Skin Cells of Adult Frogs" (1975), by John Gurdon, Ronald Laskey, and O. Raymond Reeves

In 1975 John Gurdon, Ronald Laskey, and O. Raymond Reeves published "Developmental Capacity of Nuclei Transplanted from Keratinized Skin Cells of Adult Frogs," in the Journal of Embryology and Experimental Morphology. Their article was the capstone of a series of experiments performed by Gurdon during his time at Oxford and Cambridge, using the frog species Xenopus laevis. Gurdon's first experiment in 1958 showed that the nuclei of Xenopus cells maintained their ability to direct normal development when transplanted.

Format: Articles

Subject: Experiments, Publications

W. J. Crozier

Format: Photographs

Subject: People

Circulatory Changes at Birth

When placental mammals are born their circulatory systems undergo radical changes as the newborns are prepared for independent life. The lungs are engaged, becoming the primary source of fresh oxygen, replacing the placental barrier as a means for blood-gas exchange.

Format: Articles

Subject: Processes

J. Percy Moore

Format: Photographs

Subject: People

Gregory Goodwin Pincus (1903-1967)

Gregory Goodwin Pincus, one of the original researchers responsible for the development of the first oral contraceptive pill, was born in Woodbine, New Jersey, on 19 April 1903 to Russian Jewish parents. In 1924 Pincus received his BS degree from Cornell University, and in 1927 he received his MS and PhD from Harvard University, having studied under William Ernest Castle and William John Crozier.

Format: Articles

Subject: People, Reproduction

"The Development of the Pronephros during the Embryonic and Early Larval Life of the Catfish (Ictalurus punctatus)" (1932), by Rachel L. Carson

Rachel L. Carson studied biology at Johns Hopkins University in Maryland and graduated in 1933 with an MA upon the completion of her thesis, The Development of the Pronephros during the Embryonic and Early Larval Life of the Catfish (Ictalurus punctatus). The research that Carson conducted for this thesis project grounded many of the claims and observations she presented in her 1962 book, Silent Spring.

Format: Articles

Subject: People, Experiments, Publications

"The Results of Operations for the Cure of Cancer of the Breast Performed at the Johns Hopkins Hospital from June, 1889, to January, 1894" (1894), by William Stewart Halsted

In 1894, William Stewart Halsted published The Results of Operations for the Cure of Cancer of the Breast Performed at the Johns Hopkins Hospital from June, 1889, to January, 1894, in the medical journal Annals of Surgery. In the article, Halsted describes the results from fifty of his operations on women with breast cancer, performed at Johns Hopkins Hospital in Baltimore, Maryland. Those operations involved a surgical procedure Halsted called radical mastectomy, which consists in removing all of the patient’s breast tissue, chest muscle, and underarm lymph nodes.

Format: Articles

Subject: Publications

"The Developmental Capacity of Nuclei Taken from Intestinal Epithelium Cells of Feeding Tadpoles" (1962), by John B. Gurdon

In 1962 researcher John Bertrand Gurdon at the University of Oxford in Oxford, England, conducted a series of experiments on the developmental capacity of nuclei taken from intestinal epithelium cells of feeding tadpoles. In the experiments, Gurdon conducted nuclear transplantation, or cloning, of differentiated cells, or cells that have already specialized to become one cell type or another, in tadpoles. Gurdon's experiment showed that differentiated adult cells could be induced to an undifferentiated state, where they could once again become multiple cell types.

Format: Articles

Subject: Experiments

"Derivation of Pluripotent Stem Cells from Cultured Human Primordial Germ Cells" (1998), by John Gearhart et al.

In November 1998, two independent reports were published concerning the first isolation of pluripotent human stem cells, one of which was "Derivation of Pluripotent Stem Cells from Cultured Human Primordial Germ Cells." This paper, authored by John D. Gearhart and his research team - Michael J Shamblott, Joyce Axelman, Shunping Wang, Elizabeith M. Bugg, John W. Littlefield, Peter J. Donovan, Paul D. Blumenthal, and George R. Huggins - was published in Proceedings of the National Academy of Science soon after James A.

Format: Articles

Subject: Publications

“Infant Survival After Cesarean Section for Trauma” (1996), by John A. Morris, Jr. et al.

In the May 1996 edition of The Annals of Surgery, John A. Morris and his collaborators published “Infant Survival After Cesarean Section for Trauma,” in which they evaluate the use of emergency cesarean sections for the treatment of pregnant trauma patients. During a cesarean section, a physician removes a fetus from a pregnant woman through an incision in her abdomen and uterus. When a pregnant woman experiences trauma, physicians can perform an emergency cesarean section to remove the fetus and administer medical treatments that would not be possible while the woman is pregnant.

Format: Articles

Subject: Publications

"Apoptosis: A Basic Biological Phenomenon with Wide-Ranging Implications in Tissue Kinetics" (1972), by John F. R. Kerr, Andrew H. Wyllie and Alastair R. Currie

"Apoptosis: A Basic Biological Phenomenon with Wide-Ranging Implications in Tissue Kinetics" (hereafter abbreviated as "Apoptosis") was published in the British Journal of Cancer in 1972 and co-authored by three pathologists who collaborated at the University of Aberdeen, Scotland. In this paper the authors propose the term apoptosis for regulated cell death that proceeds through active, controlled morphological changes. This is in contrast to necrosis, a passive mode of cell death that results from uncontrolled cellular reactions to injury or stress.

Format: Articles

Subject: Publications

My Father, My Son (1986), by Elmo Zumwalt, Jr., Elmo Zumwalt III, and John Pekkanen

My Father, My Son is a dual autobiography by father and son Elmo Russell Zumwalt Jr. and Elmo Russell Zumwalt III published by Macmillan Publishing Company in 1986, detailing their experiences during the Vietnam War and particularly with Agent Orange, an herbicide used for defoliation and crop destruction during the war. As a commander in the Navy, Zumwalt Jr. ordered the use of Agent Orange in South Vietnam, where Zumwalt III was stationed.

Format: Articles

Subject: Publications