Monday, Mar. 19, 2001

Dead Men Tell No Tales--But Bugs Do

By Sandy M. Fernandez

Even to the most hardened investigators, the worst part of examining a decomposing corpse can be coping with its buzzing, wriggling, burrowing infestation of flies, maggots and other insects. Even coroners--not normally the queasiest of folk--can find themselves affected. But to Canadian Gail Anderson, 39, "it's really just a science." Professor Anderson is head of the forensic entomology laboratory at Simon Fraser University in British Columbia. It is the first university lab in North America founded for the sole purpose of refining the ways in which insect biology can help solve crimes.

While a grad student, Anderson began her career when a professor recommended her as a source to police. In the 12 years since, she has assisted with more than 130 homicide probes, helping determine, among other things, the time and cause of death and whether a body has been moved. Insects can offer this information because they are so predictable: a species will tend to stick to certain foods and environments, and given the same weather conditions, its members will develop at the same pace. Comparisons with baseline data will quickly tell the age of a particular specimen--and thus the time of death--and whether it has been transferred from its normal habitat.

In one of Anderson's cases, witnesses claimed that a murdered woman had been alive, shopping at the mall, days after two young men said they had seen her slain. With the jury unsure whom to believe, insect evidence led the way. "I was able to tell them, 'No, she was very dead by then,'" says Anderson. Bugs can sometimes tell investigators what a corpse cannot. After body tissues have rotted away, insects that have been feeding on them can still be tested for drugs or poisons. Anderson does the analysis herself, but in most cases she depends on police to collect the specimens--which means training the officers to do it properly and thoroughly. "One maggot doesn't help me," she says. DNA technology promises greater advances in her field. Recently, the FBI matched a suspect to his dead rape victim by the blood contained in a single louse that had migrated from him to her.

In 1998 Anderson and her students began compiling a nationwide database on the habits of flesh-eating insects native to Canada--the first time such a resource has been put together for any country. They are examining hundreds of insects that have never before been studied for forensic purposes. Anderson is also moving beyond bugs to other creatures. In October she submerged six pig carcasses in Howe Sound, hoping to develop basic guidelines for how saltwater animals like crabs and shrimp interact with corpses. Though oceans have always been a favorite dumping ground for bodies, this type of research hadn't been conducted since the 1800s. Anderson's biggest challenge now? Cash. "Most funders like their money to go toward studying live people," she says. "I tell them the dead have rights too."

--S.M.F.