The bugs crawl in, the bugs crawl out

Once on the scene, Goff collects samples of every insect developmental stage present -- eggs, maggots, pupae and adults -- taking them back to his laboratory for identification, preservation and hatching. He incubates samples of maggots and pupae under suitable conditions, noting how long it takes for adult insects to emerge, and uses the results to date the time of death. Armed with photos from the scene, insect and weather data and pig decomposition studies as a reference, he calculates the time required for the body to reach the state of decomposition in which it was found, estimating the postmortem interval.

Without pig studies to provide clues to patterns of insect activity, very little of Goff's work would be possible. With characteristic bluntness, he writes of an early investigation: "Since I was attempting to duplicate a homicide, in one of my first studies I wanted to shoot each pig through the head with a 38-caliber pistol." Which he did.

To duplicate insect activity found in beached drowning victims, Goff threw dead pigs into the sea; he also strung up dead pigs in trees to imitate suicide by hanging, wrapped them in blankets to re-create concealed bodies and mimicked arson victims by dousing pigs in gasoline and setting them alight.

"It is disconcerting to be collecting maggots from one end of a pig and look up to find a mongoose eating at the other end," Goff writes in his book, helpfully reminding readers to make sure the decomposing pig is sufficiently protected from noninsect predators. While carrying out a pig decomposition study, Goff visits the study site several times each night to monitor insect activity.

Although Goff's research may sound like bad news for pigs, the decomposition studies provide him with invaluable archival data to compare with insect evidence found in criminal cases. With that data, he can extrapolate a postmortem interval to within a few hours, and he has frequently provided courtroom testimony discounting or supporting a suspect's alibi.

Goff's work takes him annually to the FBI Academy in Quantico, Va., where he teaches part of a weeklong course on the detection and discovery of human remains. He also travels extensively, investigating cases on the mainland and teaching training sessions worldwide. But Goff always returns to Hawaii, eager to conduct further studies to better understand the role of insects in decomposition. "I think I've got a lot more questions now than when I started," he says.

In Oahu's tropical environment Goff has found the perfect place to answer some of them. As night gathers and the tangled knots of vegetation tighten in the faltering light, the air becomes alive with insects.

A fecund and secretive place, the forest is like a machine, and as with all machines, it requires fuel to thrive. The same is true of the orderly sugar cane fields, the lazy coastal towns, the inland cities and almost any other environment. Dead organic matter is the fuel that drives any ecosystem, and insects, toiling away unseen, are the tools with which it is broken down and returned to the soil. "The whole pattern, the whole puzzle, is so complex and so intriguing," Goff says. "These are very complex systems, and we're part of it, sometimes in ways we don't want to be."

In several of Goff's decomposition studies, insects began to colonize corpses within 10 minutes; and in some of his more gruesome studies, they did not even wait for death to occur before beginning to feed. His vivid descriptions of murder victims as centers of frantic insect activity are a reminder that we are just animals, as available and irresistible as roadkill to a passing blowfly.

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