Identifying a crime victim from skeletal remains is part art and part science, relying on specialists with expertise ranging from anatomy and anthropology to insects and DNA.
Even the tiniest of details is relevant, said Dr. Lawrence Kobilinsky, a forensic scientist at John Jay College of Criminal Justice in Manhattan.
The state and type of bugs found on or near skeletal remains can help determine how long a body had been there. Bugs invade grave sites in different waves, he said. Burrowing, nonfeeding insects found near the body indicate a person has been dead for years, possibly decades.
Forensics experts are examining a human skull, which sources said may have been there for years, and a set of bones found Monday off Ocean Parkway east of Jones Beach State Park. While the Suffolk and New York City medical examiners' offices would not disclose what methods they are using to identify the skull and bones, investigators have in the past created three-dimensional models of a face using a skull.
"The first thing you need is a report from an anthropologist and that will tell you the person's sex, approximate age and possibly the ethnicity," said Gloria Nusse, a San Francisco-area forensic artist and anatomist who helps detectives identify crime victims. She said a face has 32 "anchor points" that help anatomists construct an image.
"There are specific landmarks on the [skull] that we measure to help us build up the face," she said. "These landmarks are based on measurements have been published for over 115 years and are based on studies from all over the world.
"Using the landmarks we rely on helps us create a reasonable model of what the person might have looked like."
Nusse, who teaches anatomy at San Francisco State College, said there are two types of identification: presumptive and positive. Presumptive identification would be a face developed from modeling. Positive identification is obtained from fingerprints, DNA or dental records, for example.
"Physical and biological evidence can lead to the name of an individual," said Kobilinsky, who chairs the department of forensic science at John Jay. DNA can be extracted from any remains, including bones, Kobilinsky said; however it's more difficult to extract genetic data from skeletal remains than soft tissue.
DNA can be compared to the genetic profiles of relatives, he noted, who might come forward after seeing the published or televised image that emerges from forensic modeling.