Ernest Everett Just, PhD 1916, worked with University of Chicago zoologist Frank Lillie at what is now the Marine Biological Laboratory in Woods Hole, Massachusetts. During dissertation research for his PhD in zoology, he made an important discovery about cell cleavage, showing that the sperm entry point determines the first cleavage plane in the egg of the marine annelid Nereis limbata.
Botanist Henry Chandler Cowles’s study of ecological succession in the Indiana Dunes along the southern shore of Lake Michigan in the late 1890s opened a new field of inquiry in the natural sciences: ecology. The investigation of a changing natural landscape carries increasing importance amid growing concerns about our environment.
Biochemist Donald F. Steiner, SM’56, MD’56, discovered proinsulin, the first “pro-hormone” and precursor to insulin. The 1965 finding led to the synthetic production of human insulin, markedly improving therapy for diabetes sufferers, and laid the groundwork for improved understanding of how other proteins in the body are made.
On a survey in Ethiopia, in 1974, paleoanthropologist Donald Johanson, AM’70, PhD’74, discovered “Lucy,” a 3.2 million-year-old bipedal hominin skeleton that was 40 percent intact. Classified in 1978 as the first known member of Australopithecus afarensis, Lucy is a direct ancestor of the modern human. The discovery changed our understanding of human evolution.
Beginning in the 1990s, paleontologist Paul Sereno’s discoveries of previously unknown dinosaur species on several continents have contributed to the understanding of the dinosaur family tree and to the larger question of how evolution works over millions of years.
