In his 1907 paper, “Experiments in Transplanting Limbs and Their Bearing Upon the Problems of the Development of Nerves,” in the Journal of Experimental Zoology that he edited,

Gustav Jacob Born was an experimental embryologist whose original work with amphibians served as the platform for his wax-plate method of embryo modeling, heteroblastic (different tissues) and xenoplastic (similar species) transplantation methods, environmental influences on sex ratio studies, and proposed function of the

John Spangler Nicholas, an American biologist, was born on 10 March 1895 in Allegheny, Pennsylvania. He was the only child of Elizabeth Ellen Spangler, a teacher, and

Otto Mangold was an early-twentieth-century embryologist who specialized in the development of amphibian embryos. A major emphasis of his research was refining the concept of the organizer, now referred to as