For nearly three decades, the Nobel Prize-winning economist Robert W. Fogel and a small clutch of colleagues have assiduously researched what the size and shape of the human body say about economic and social changes throughout history, and vice versa. Their research has spawned not only a new branch of historical study but also a provocative theory that technology has sped human evolution in an unprecedented way during the past century.

Next month Cambridge University Press will publish the capstone of this inquiry, “The Changing Body: Health, Nutrition, and Human Development in the Western World Since 1700,” just a few weeks shy of Mr. Fogel’s 85th birthday. The book, which sums up the work of dozens of researchers on one of the most ambitious projects undertaken in economic history, is sure to renew debates over Mr. Fogel’s groundbreaking theories about what some regard as the most significant development in humanity’s long history.

Mr. Fogel and his co-authors, Roderick Floud, Bernard Harris and Sok Chul Hong, maintain that “in most if not quite all parts of the world, the size, shape and longevity of the human body have changed more substantially, and much more rapidly, during the past three centuries than over many previous millennia.” What’s more, they write, this alteration has come about within a time frame that is “minutely short by the standards of Darwinian evolution.”

“The rate of technological and human physiological change in the 20th century has been remarkable,” Mr. Fogel said in an telephone interview from Chicago, where he is the director of the Center for Population Economics at the University of Chicago’s business school. “Beyond that, a synergy between the improved technology and physiology is more than the simple addition of the two."...