Researchers at the University of Montana are working to develop new methods of measuring the features of the human skull, shedding light on how they’re controlled by genetics while growing to meet the demands of our environment.
With a plastic skull in her hands, Mary-Margaret Murphy, a UM graduate student in anthropology, noted the cranial bone structures that make each of us unique. Somewhat like a fingerprint, these features can, to a trained eye, reveal anthropological clues to one’s heritage and origin.
Who were your ancestors? Where are you from? What environmental conditions did you adapt to thrive in? Our bones tell stories long after we’re gone.
“The features of the face can be broken down to the shapes they form,” Murphy said. “Your design is genetic, so you look like your relatives. But there are environmental factors as well.”
New digital technology can now be used to scan cranial features, opening up exciting possibilities for researchers like Murphy.
A three-dimensional scanner sits on her desk. When placed against a dotted background and filmed with a projector, each skull reveals a unique pattern, giving clues to the person’s past.
Yet despite the advances in technology, challenges linger in how researchers go about their measurements. While certain structures are telling, others often are neglected, and researchers typically apply their own measuring tools, making it difficult to compare data sets and populations.
In her lab in the Social Sciences Building, Murphy has embarked on a quest to standardize they way craniums are measured. If successful, the methods could be used across the spectrum, allowing scientists to compare populations.
“We’re starting to use 3-D data more in research, but everyone’s doing something different,” said Murphy. “It’s difficult to compare and replicate the research if you haven’t collected your data in the same way.”
Murphy turns the skull and names the bone features – the superorbital torus and the frontal temporal suture. She then explains the challenges of inventing what she called a “universal sectioning system for measuring” these features.
It’s an amazing science that focuses in part on the features that make each of us unique in appearance and place us among certain population groups. The prominence of the brow, the rise of a cheek and the shape of an eye – they are revealed in the bone structures that give our faces shape.
“I’m working to standardize a way of sectioning off cranial areas so we can scale them together and compare them for structure and curvature, as opposed to using just the (bone) points,” Murphy said. “If we’re using the same ruler, so to speak, then we can compare what it is we’re doing.”
Murphy describes herself as a statistician with an interest in scientific illustration. Mathematically inclined, she’s working to develop that so-called standard ruler while building new data sets, allowing researchers to compare cranial features across populations.
The more measurements she collects, the more patterns will begin to emerge. Combined with a standardized system for measurement, the new technology could help advance anthropological research through the study of cranial morphology.
“My hope is that patterns will show the balance between the effects of genetics and environment on the structures,” Murphy said. “That’s the anthropological angle, but it also shows changes in morphology as people move across the Earth.”
Murphy’s efforts to enhance the process may benefit an ongoing study already taking place on cranial morphology. Her former adviser, Noriko Seguchi, already has collected data sets from the Ryukyu Islands south of Japan.
Murphy will begin to take the incomplete cranial scans and align them into complete three-dimensional images. In the process, she’ll contribute to building that ever-important data set and make it available to wider research.
“Having the remains in a digital format allows them to be transmitted to other experts in a format where they can actually be three-dimensionally printed,” she said. “If we have digital formats, we have the ability to continue to learn from them and in different places, regardless of where their repository is.”
Reporter Martin Kidston can be reached at 523-5260, firstname.lastname@example.org or @martinkidston.