Penn Museum's Morton Skull Collection at Center of Scientific Dispute

Samuel George Morton, a 19th-century physician and physical anthropologist, best known for his measurement of human skulls, has long been held up as a prime example of scientific misconduct. According to the late Stephen Jay Gould, one of the world’s preeminent evolutionary biologists and scientific historians, Morton skewed his data about cranial size to fit his preconceived and racist notions about human variation.

But a team of six anthropologists has taken another look at Morton’s collection of skulls (which include 1,200 in the original collection, and 2,000 in total) and has determined that Morton did not manipulate his data to support his controversial ideas, as Gould claimed. The authors write that Morton took measurements of the skulls to determine whether human populations were separate species from multiple divine creations or a single species created once, a central question in pre-Darwinian science.


“[Morton’s] methods and his data do not suffer from the errors and the bias that Gould suggests,” says Jason E. Lewis, a former Penn student and lead author of the study published in the June 2011 issue of PLoS Biology.

Gould, who died in 2002, charged in his 1981 book “The Mismeasure of Man” that Morton had selectively reported data, manipulated sample compositions, made analytical errors and mismeasured skulls in order to support his prejudicial views about the intelligence of different human groups.

Lewis cautions that the research team is not disputing that racist views were common in 19th-century science, or that bias has influenced scientific research in some cases. But they say in their paper, “The Mismeasure of Science: Stephen Jay Gould versus Samuel George Morton on Skulls and Bias,” that most of Gould’s claims about Morton are poorly supported.

“We had known for a long time—having been with the Morton collection, and always fact-checking on things—that Morton was a meticulous scholar, and you wonder when you see that played out on the ground, how he would have really fudged his data,” says Janet Monge, acting-curator-in-charge of the Physical Anthropology Section of the University of Pennsylvania Museum of Archaeology and Anthropology, and co-author of the paper. “On the occasions when we were verifying any of the data ... we found that [Morton] was a good scientist to the point of almost an obsession.”

To test Gould’s claim that Morton had skewed his data, the team relocated and re-measured almost half the skulls that Morton had originally examined. Much of the collection, considered one of the best in the world, resides at the Penn Museum.

This study is important, the authors say, because Gould used Morton as his main support for his claim that bias in scientists is inevitable. “You can say, ‘Well, this is a guy from the past, it doesn’t really matter,’” says Monge. “It does matter in the same way that it matters for Gould that he didn’t do the legwork, it matters for Morton that essentially he did do the legwork.”

Text by Heather A. Davis
Photos by Steve Minicola
Video by Kurtis Sensenig