Thursday, February 26, 2009
Scientist Helps ID the Remains
By Leslie Linthicum
Journal Staff Writer
Aside from the gruesome speculation that goes along with finding a possible serial killer's graveyard on the edge of your city, there is the matter of the bones.
Police have been swarming the plot of sand at 118th Street and Dennis Chavez SW since bones were discovered there Feb. 2. The count is now up to the remains of 10 people, plus one fetus.
It has been a horrifying and captivating tale, ably advanced each day by the Journal's Jeff Proctor. Many of his stories over the past three weeks have included the term "human remains," and that brings us to the inevitable question: Who were these people?
So I walked down a hallway on the University of New Mexico campus Wednesday until I got to an office with a red hand-lettered sign on the door that read: "You can really learn an awful lot from human remains."
Heather Edgar, the curator of human osteology at UNM's Maxwell Museum, greeted me in a bit of a fluster. She has been busier than usual since the graveyard was found on the West Mesa.
Human osteology, also called bioarchaeology, is the study of human bones, and it is what builds the bridge between the discovery of "human remains" and the notification of family members, the solving of a homicide and the holding of a proper memorial service and burial of the dead.
Edgar has been out to the 118th Street site, and she'll be there again today. She wasn't talking to me Wednesday about the specifics of the current case, but she walked me through the seemingly impossible steps that take us from the finding of a thigh bone to the police chaplain's knock on a door.
The first question is, is it human?
"It takes me a half-a-second, normally, to tell if a bone is human or not human," Edgar says. That's because she's been working with bones for quite a while, and the shapes or characteristics that would be lost on a layman immediately pop out to her.
In that half-a-second, what helps her make the call? Shape, size and density.
If you and I were to look at a deer femur or a human femur, we probably couldn't tell the difference. But Edgar can see a difference in how dense the top layer of bone appears, the shape of the knob where the leg bone meets the pelvis and size: The human bone is bigger.
The next question is, how old is it?
"This question of how long has a person been dead may be the most difficult of all the questions," Edgar says. A host of things influences how a body degrades, and its bones change over time.
"Where it is; what kind of soil it's in. Is it dry or wet? Is it in a house or is it in a box? Is it in the desert? Is it in a car or up in a tree? Did the person die in the summer or the winter? Were there a lot of bugs around or not? Were there coyotes? Just innumerable factors," Edgar says. "It's really the most difficult question."
The answer to how long a body has been in the ground tells the forensic anthropologist whether this is a skeleton of historical or anthropological concern, or whether it is a matter for the police.
If it's a relatively recent human skeleton, the question becomes one of specific identity, and the scientists start by determining age, gender, ancestry and, of course, how the person died.
The two most helpful bones for identification are the pelvis and the skull. A pelvis can quickly settle the question of gender (a woman's is wider in almost every measurement), and a skull lends detailed information about gender (men have broader brows) and ancestry (an Asian's cheekbone and an African-American's tooth, for example, have distinctive characteristics).
"The less you have of a skeleton, unless you're lucky and you get exactly the right piece, the harder it is to tell anything about it," Edgar says. "Sometimes it's a jigsaw puzzle."
A positive identification is usually made by a match of dental records or some other medical record say, an X-ray. But there are a lot of dental records for a lot of missing people. Police investigators don't check a found skull against every set of dental records of every missing person. They couldn't.
"If we can say it's a person of about this age, they're male, they are European-American and they're over 6 feet tall, then we've narrowed your pool," Edgar says.
The same techniques that are employed by forensic anthropologists for crime scene work help in the larger picture to understand how people used to live and how we and our cultures change over time.
But right now at the Office of the Medical Investigator with only two of the victims identified and the rest being referred to as Jane Doe the race is on to bring names and faces to the dead.
"It's an amazing service that we can help with," Edgar says. "I think it's a gift to be able to do this for people. It's a sad gift, but it's a gift."
UpFront is a daily front-page opinion column. You can reach Leslie at 823-3914 or firstname.lastname@example.org. Read all of her columns at ABQJournal.com/upfront.