'Last responders' find bare-bones clues

Oregon's forensic anthropologist speaks at the Kiggins Theatre

By Patty Hastings, Columbian breaking news reporter

Published:

 

Human bones

• There are 206 bones in the human body.

• Each hand contains 27 bones.

• Each foot contains 26 bones.

• A person has 52 teeth in his or her lifetime.

When human remains are found in the wilderness, forensic scientists are among many responders who come to the scene.

Nici Vance, Oregon's state forensic anthropologist, joked that she and her colleagues often call themselves "last responders." Their job is to identify someone who's been found, based on what's left of their skeleton, and possibly piece together how they died.

She spoke Wednesday night at the Kiggins Theatre in downtown Vancouver about what facts can be revealed through a person's bones.

"When a body doesn't have weighable organs, they give it to me," she said during the event, the third in a local series of science lectures called Nerd Nite.

Overwhelmingly, the remains she gets aren't full, clean bodies you see on TV shows such as "CSI." Vance gets bones or mummified bodies and has to figure out who they belong to and what happened to them.

The first step is to determine whether what she's looking at is a bone (She gets plastic pipes and landscaping rocks sent to her). Once she has that squared away, she sets about determining the individual's gender and age.

Men and women's skulls have defining characteristics. A woman's skull will have a more graceful, sloping brow and slighter chin than a man's. A man's pelvis will be narrower, lacking the birth canal that women have. Figuring out age starts with the teeth.

"Children have a head full of teeth," Vance said.

Children's teeth grow in and fall out at a standard rate, so she can estimate the age of a child based on the development of the teeth in their heads. Children also have cartilage in their bones that doesn't fully fuse until they become young adults. Then, the appearance of the skeleton is relatively static through the 20s and 30s, making the exact age of people in this group of adults more difficult to pinpoint.

Once a person reaches their 40s, bone density decreases. As a person ages, there are degenerative changes to the vertebrae of the spine in the lower back. Someone might even have a prosthetic fused with their bones, and Vance can get an idea of how long the hardware has been there.

Long bones, such as the femur and tibia, help determine someone's height. Although a skeletal analysis doesn't provide direct evidence of skin color, the cranial features can indicate whether the person was of African, Asian or European descent. Vance said she looks at the nose and eye holes for these clues.

Any trauma to the bone can indicate how someone died. A gunshot wound, for instance, fractures the bones around the entry point.

All of these factors help narrow down the group of people that the human remains might belong to. The remains can then be matched up with missing persons to help bring closure to families dealing with a lost loved one, Vance said.