Probably all of us have, at one time or another in our younger years, been told to stand up straight. If you’re part of Generation X or the early Millennial cohort, you probably had to undergo an exam during middle school for scoliosis, an abnormal curvature of the spine. If you’re a Baby Boomer, you might have had to take a posture test upon entering college — or even to pass one before you could graduate. But where did this concern for proper posture come from? Beth Linker, a historian and sociologist of science at the University of Pennsylvania, explores this question in her new book Slouch: Posture Panic in Modern America.

Linker finds that the modern scientific and medical obsession with poor posture emerged in the wake of Charles Darwin’s 1859 On the Origin of Species, which posited that what truly differentiated humankind from apes was not intellect but bipedalism. By the turn of the twentieth century, many scientists and public health officials worried that slouching would lead to degeneration and disease. A famous 1917 study found that nearly four-fifths of Harvard’s freshman class had poor posture, which sparked the widespread adoption of posture exams in schools, workplaces, and the military, along with public and commercial efforts to correct deficient stances. Poor posture became what Linker calls “a sign and signal for everything from sexual deviancy and racial degradation to unemployability and chronic disease… Posture examinations became a way for government officials, educators, and medical scientists to evaluate not only overall health but also moral character and capabilities at the individual and population levels.”

In fact, what Linker calls the “posture panic” wasn’t based on any real connection between a person’s posture and their morality, their abilities, or their long-term health — although she argues that scientific study of the effectiveness of posture correction was inhibited by the 1990s scandal over the Ivy League’s past practice of taking nude posture photographs of entering freshmen. In this podcast, Linker discusses the history of posture panic, the widespread adoption of student posture exams that later excited public speculation about nude photos of George W. Bush and Hillary Rodham (among others), the way that the disability rights movement and the demise of in loco parentis ended the practice of university posture exams, and how we ought to regard posture science in hindsight.