Glendive native published in JAMA

Hunter Herbaugh
Sunday, June 21, 2020
Article Image Alt Text

Dr. Diana Thomas

A Glendive native has been making national headlines as her recent mathematical work is being featured in a major medical publication. Dr. Diana Thomas, a graduate of the Dawson County High School Class of 1987 and a professor of mathematics at West Point, is being recognized for her role in a study comparing the proportions of the average modern human body with Leonardo da Vinci’s Vitruvian Man.

Thomas grew up in Glendive and is well-known by many local residents. Her father was a local doctor and she and her siblings all graduated from DCHS. As a member of the Class of ‘87, her last year at the school was the first year that calculus classes were taught. She noted that she fell in love with math then, especially as she was taught by Fenn Wilkinson, a highly respected math teacher at the time.

As she went on to major in mathematics, Thomas also continued pursuing her dream of having her work published in the Journal of the American Medical Association (JAMA). Her first introduction to the publication was as a young girl in her father’s waiting room.

Thomas explained that getting your work published in JAMA is a huge accomplishment because they are very selective.

“Getting published in JAMA is like shooting fish in a pond with a pen,” she said.

In her career, Thomas has published over 130 peer-reviewed studies, according to her West Point profile, but this is her first time being included in JAMA. Most of her work has been related to exercise, weight loss, obesity and other topics regarding the human body. However, she noted that getting this particular study into the Vitruvian Man published in JAMA was exceptionally exciting because of how different it is from her other works.

The Vitruvian Man is a famous illustration that da Vinci created around 1490 and hypothesizes the ideal proportions of the human body. It depicts a man standing in two different poses, superimposed over each other, his arms and legs spread apart and inscribed in a circle and a square. In da Vinci’s design, one of the poses depicts the man’s arms held up and spread, with the tips of his fingers level with the top of his head while his legs are spread apart, forming a circle with the center point being his naval. The other pose depicted has the man standing straight with his arms held straight out in a “T” shape and a square drawn around him with each side touching his feet, fingers and head. The center point of the square is the man’s groin.

Using measurements from thousands of modern day men and women, Thomas’ study found that the average bodies of people today aren’t too far off from the proportions of da Vinci’s ideal person.

“Despite the different samples and methods of calculation, Leonardo da Vinci’s ideal human body and the proportions obtained with contemporary measurements were similar,” the team of researchers led by Thomas reported, per the associated press.

Thomas explained that the samples for this study came from body scans of Air Force recruits that are done when fitting them for their uniforms. When one of her colleague’s gave her the idea, Thomas realized that she already had a pretty extensive collection of body types to use in her calculations.

“When people arrive at (Joint Base San Antonio) Lackland, where they go through training, they are scanned so that their uniforms are fitted. We already had a large amount of samples, so we were able to use those,” Thomas said.

When put together, the average height for the modern male equalled approximately five feet, six inches and the average female came to about five feet, three inches, both of which are taller than the man in da Vinci’s design. The recruits were between the approximate ages of 17 to 21.

As part of the study, Thomas said that she and her team recruited a professional artist to draw two modern day versions of the Vitruvian Man, one male and one female, as well as redraw da Vinci’s original sketch. The measurements of the modern day subjects’ bodies were then compared to da Vinci’s notes. In summary, the study found that da Vinci’s estimates of the perfect human form were within 10 percent of matching the human body.

“Except for arm span and thigh length, the differences in proportions for men measured by the body scanner and ‘Vitruvian Man’ were within 10% [concurrence],” the West Point researchers said. “The difference in arm span was 20% and difference in thigh height was 29% more than ‘Vitruvian Man.’”

“It’s amazing that we can take this sketch and these notes from 500 years ago and compare them to now,” Thomas said.

The Vitruvian Man is based on the correlations of ideal human proportions with geometry described by the ancient Roman architect Vitruvius in Book III of his treatise De Architectura from the first century A.D. Along with his own research, da Vinci used Vitruvius’s work to create his own interpretation of Vitruvius’s original hypothesis.

Reach Hunter Herbaugh at