Take ribs, for instance. George stood near a donor, almost entirely skeletonized, whose ribs were cracked. One might surmise that these broken ribs were a clue to how the person had died. But she says the bones were broken in the enclosure, from a vulture sitting on them. She wouldn’t have believed it herself if the whole thing hadn’t been captured on camera. Then she pointed to a body up on the plateau, at the far end of the enclosure. That donor, she said, did break their ribs when they died. The breaks looked totally different, the fractures more jagged. That’s because, George said, the breaks occurred in living bone, not after death when the material is more brittle. In a third body, Passalacqua pointed out a small spike on the rib. That, he said, was also a rib fracture, but one that had healed while the donor was alive.
Chronic illnesses and some other diseases can manifest in the bones. Tuberculosis can spread there, causing lesions. Forensic anthropologists can estimate a deceased young person’s age by understanding how the skeleton changes over time. Older adults, too, might have distinctive markers of age, like bone loss. But this work is difficult, and there’s still a lot scientists don’t know. Donors like these help them learn more.
George and Passalacqua’s job is to teach students, along with the law enforcement workers who occasionally train there, how to learn what you can from a body. Oftentimes, their first step is to figure out if a bone is human. Passalacqua regularly receives texts from local law enforcement asking about bones they’ve found—a partial skeleton of a bear paw looks shockingly like a person’s hand.
One of the hardest things for forensic anthropologists to do is also one of the most essential: estimating the time that has passed since death. “There are just so many variables that are really difficult to account for,” says Passalacqua. A reputable forensic anthropologist will rarely be able to say, for instance, that a body has been dead for exactly three weeks. More likely is a range of, say, one week to two months. That’s not as useful to law enforcement officers who are trying to solve a crime.
By the time I arrived, Donor X was already in advanced decay, but every day, this donor will teach living people something. When there’s little left on the bone, students will carefully remove the body from the FOREST and bring it to the lab. The bones will be cleaned by hand, and perhaps gently simmered to remove the last bits of tissue. They will be laid out and examined. And then they will be packed up, the delicate pieces placed in cheesecloth bags, and stored in the university’s collection, labeled in identical cardboard boxes.
But for now, Donor X remains in place, slowly becoming a unique microbiome. Dense trees filter the sunlight. The vultures aren’t there that morning, so as we walk and the students quietly examine a donor’s bones, the only other sounds we hear are the calls of cicadas.