In a small laboratory at the heart of McMaster’s campus, fourth-year History and Anthropology student Grace Clack lifts a 200-year-old skull to the light. Above the right temple, she sees it: a clean, deliberate cut. It would spark a yearlong investigation, part archaeology, part medical history, into a child’s life and death.
Clack works in professor Megan Brickley’s paleopathology lab, which studies disease and injury in ancient remains and recently received a significant loan of 114 skeletons recovered during the redevelopment of a parking lot in Guelph.
Loaned under approved ethical protocols, the remains are being studied with care and respect to better understand patterns of health and disease in 19th-century Upper Canada.
Soon after the collection arrived at McMaster, Brickley assembled a team of research assistants (RAs) to sort through the collection, clean the bones and perform important research.
And as soon as Clack heard about the project, she jumped at the opportunity to get involved, taking the prerequisite course and emailing Brickley to apply for a position in the lab.
The first task was a little gruesome. The team painstakingly cleaned every bone, which had accumulated centuries of dirt, sometimes clearing skulls of soil.
Clack said that although, as researchers, it’s possible to keep a sense of academic distance, sometimes you’re reminded of the nature of the task.
“I’ve had lots of practice being around skeletons in anthropology,” said Clack. “There were definitely a few moments, though, where you take a step back and you realize that this person had a name, a life. I think it’s good to remember that.”
“We found what we assumed to be a mother and child who clearly died around the same time and were buried together. We took very special care to keep them together.”
It was towards the end of the cleaning process that Clack’s mystery presented itself.
Grace Clack holds a fragment of skull bearing a strikingly straight incision.
“On the last day of cleaning, a unique skeleton just caught my eye,” she said. “It was a young child who had evidence of being autopsied or dissected.”
But that’s rare in Canada. And what’s more, it was unclear whether it was an autopsy or a dissection, which had completely different purposes, and tell different stories about the child’s life.
One is to establish a cause of death, the other for science or education. Autopsies were quite exclusive at the time and had to be paid for privately. And historically, dissections in the 19th century frequently drew on bodies from society’s margins through legal and illicit means, said Clack.
It was a chance for Clack to combine her skills in anthropology in history, to examine the social context through primary sources to see if dissections and autopsies were being performed in 19th-century Guelph.
Using her anthropological expertise, Clack investigated the skeleton for injuries, quickly finding a distinct cut on the right side of the skull. But that only added to the mystery.
“Basically, the autopsy that was conducted was fairly standard,” said Clack. “They just did a circumferential craniotomy around the head to take the brain out. But they also cut down into the right temporal bone, which is very odd.”
Clack looked closer, using high-powered digital microscope to investigate the area around the cut. She found lesions around where the ear was, leading her to believe that there may have been an ear-related illness. The problem? Clack had no experience with ear disease.
Fortunately, though, she had a mentor in Brickley who is one of the world’s leading paleopathologists – an expert in ancient disease and injury.
Clack was mentored by McMaster professor Megan Brickley, a world-renowned paleopathologist.
Brickley coached Clack to consider some options which eventually led to Clack studying some ear diseases that were consistent with the lesions on the skull.
And that’s when Clack leaned into her skills in history.
She pored through death records from the period, looking for causes of death that could be consistent with ear infections, such as meningitis, examining how common they were in Guelph at the time.
All of it tied together to allow Clack to establish with confidence that it was an autopsy. But there are still a few mysteries yet to uncover.
“I can’t say which type of ear infection we found,” she said. “Because the temporal bone region is so fragile, and the lesions are deep within the bone, making it hard to investigate.”
But through an Undergraduate Student Research Award this summer, Clack has the opportunity to use micro-CT scanning to look inside the bone, giving a clearer indication of the ailment.
She’ll be supervised by Brickley, giving Clack another opportunity to work with a researcher who has already taught her so much.
“It’s such an amazing opportunity,” said Clack. “She’s such a well-known renowned scientist that it was a little intimidating to talk to her. But we quickly realized we have interests in common. We both like to garden.”
And for Brickley, it’s a chance to train the next generation of paleopathologists by including students in real, meaningful research.
“Grace excelled in the experiential learning experience in my lab, bringing together anthropology and history in truly interdisciplinary ways. She represents the future of research at McMaster—where hands-on experience and collaboration drive discovery.”