A morbid case of sex, religion and death
During questioning, Gery insisted on his innocence, but the police knew he was lying. The investigation revealed that the suspect had telephoned his home to speak to his children from a booth near the place where the body was found, but Gery denied that he killed his wife. The combination of sex, religion and death made the case transcend public opinion. With the evidence collected, the preacher could not be indicted. Now the only hope to catch him lay in a new science against crime, theforensic entomology, where thearthropods– specifically, insects and arachnids – are required to clarify crimes. The Cologne homicide department had not overlooked the presence of larvae on the woman’s face or ants found in boots that Gery kept at his home. Could these critters solve the murder?
To clear up any doubts, the German authorities chartered a military plane to New York. On board were four passengers: a police officer and three larvae of the scavenger blowfly, Calliphora his compatriot Mark Benecke, a forensic entomologist who worked at the Chief Medical Examiner’s Office in New York. “From the size of the larvae I was able to calculate how long the corpse was in the open,” recalls the specialist. Larval development indicated that the woman was abandoned in the forest at the same time the call was made. This estimate is known as the post-mortem interval calculation.
Why do the police look in the car radiator
The second entomological evidence blaming Gery was the ant found on his pair of boots. The preacher confessed that he had never worn them. But the ant belonged to a rare species called Lasius fuliginosus, which only feeds on rotten trees and never strays more than 2 meters from the nest. The uxoricide was sentenced to 8 years in prison, even though he never admitted killing his wife. “The flies established the temporal evidence, and the ants, the geographical evidence,” says Dr. Benecke. The result of decades of research, police scientists can turn to the so-called cadaverous fauna, including arthropods, to set the date or dates of death, determine the time of year in which it occurred and verify that a corpse died on the spot. where he was found or if, on the contrary, he suffered a transfer. Far from all fiction, the insects present at the crime scene help the police solve cases of homicide, suicide and rape. They also act as snitches in drug smuggling, to reveal the routes of drug trafficking; and in the movement of terrorist groups and kidnappers. Without going any further, the identification of the crashed insects on the license plate, the windshield wiper or the radiator of the car makes it possible to establish with astonishing precision what your itinerary has been; and the eggs and larvae attached to the cannabis leaves serve as an appellation of origin stamp. And for the first time, entomological tests are being taken into account to settle cases of child abuse and neglect of the elderly, according to Dr. Benecke.
This one knows what he’s talking about. In July 2000, during an eviction proceeding for non-payment, the police discovered in an apartment in Leipzig (Germany) the semi-mummy corpse of a 2-year-old baby. Both the mother, a 20-year-old heroin addicted prostitute, and the social worker came under suspicion. Dr. Benecke determined that the child had not died in a matter of a few hours, as was initially claimed, but after being abandoned for between 7 and 14 days. The German expert was told by the insects. When processing the baby’s body, forensic entomologists found larvae in the diaper – and in the urogenital area – at a very advanced stage of the false stable fly, Muscina stabulans, and specimens of the small house fly Fannia canicularis. Adults of this species are attracted to the stench of feces and urine. The baby’s face, however, was invaded by larvae of blue flies Calliphora vomitiva, dipterans that usually come at the beginning of cadaveric decomposition. The meticulous study of the larvae and the adults, together with the record of the environmental temperature of the previous weeks, among other factors analyzed, cleared up any doubt: the baby wore the same diapers for approximately 14 days and died between 6 and 8 days before be discovered. For the first time, the cadaverous fauna made it possible to prove a case of negligence prior to the death of the victim.
In the case of insects, size does matter
“I examine the insects – larvae, pupae, adults – that have invaded the body. From the size of the animal and its stage of development I can guess how long it has lived in the corpse. And this data allows me to calculate the post-mortem interval “explains Dr. Benecke, who now heads the International Forensic Rechears and Consulting in Cologne. Today, his entomological prowess is lending it to the courts where cases of the death of the elderly abandoned and neglected by their relatives and social workers are tried, which, unfortunately, occur with increasing frequency in cases where routine investigations enter into a situation. dead end, as revealed at the last meeting of the European Association of Forensic Entomology (EAFE), which was held in Frankfurt in April 2003. Attendees advised of the need to have the arthropod expert present in the crime scene, as it can help to clarify what care the person received before being abandoned and to determine if the larvae present in the corpses arose in injuries that occurred between visits, which would excuse the social worker.
Grandma with one foot in the bag
Dr. Benecke illustrated it with several real cases, such as the corpse of an old woman whose foot was wrapped in a plastic bag. The woman died at her home in a residential area in western Germany in September 2002. Forensics found numerous larvae of the green coromid fly, Lucilia sericata, inside the bag. Given this, the social worker publicly maintained that “it is very possible that the person’s foot was wrapped in a plastic bag, and that the larvae could have been present inside when the woman was still alive.” The coroner estimated a post-mortem interval of about two days and the entomologists determined that the age of the larvae, which were 11 cm in size, was approximately four days. Now, judging by the profound loss of tissue in the foot, the insect experts considered the possibility that the larvae had fed on the old woman’s limb for at least a week before she died and then left the bag. to pupate elsewhere in the house. “Unfortunately, the apartment could not be inspected to confirm this hypothesis,” confessed Dr. Benecke in front of a fully devoted audience.
It is not surprising. Only 63 scientists around the world know how to keep track of insects. “Until very recently, researchers saw worms in corpses as a simple sign of putrefaction that had to be cleaned up immediately, rather than as potentially significant samples,” says M. Lee Goff, an entomologist at the University of Hawaii. in Manoa, in his book The Testimony of the Flies. In the 19th century, forensic entomology was hardly taken into account. Today it has earned the respect of the scientific community, to the point of becoming an essential tool of forensic medicine. “The forensic entomologist is in charge of interpreting the interaction between the arthropods and the corpse during decomposition, discarding the organisms that are present by chance, and of providing the police with all the information that may be useful to arrest and accuse the murderers, “says Dr. Lee.
Predicting visits in strong waves
In the corpses there is a successive progression of arthropods that use the decomposing remains as food and as an extension of their natural habitat. Entomologists have learned to predict how this visit occurs in waves, as each stage of rotting of a corpse selectively attracts specific species (see box on next page).
Almost everything that is known today about the decomposition of the human body and its winged visitors comes from Knoxville, Tennessee. El Dorado for anyone investigating cadaveric decay and putrefaction can be found on some university grounds. This is the Body Farm , named after the detective novel Body Farm , by Patricia Cornwell. Founded more than two decades ago by anthropologist William Bass, the Body Farm is a 1.6 hectare plot that houses dozens of human corpses in different states of decomposition that reproduce real situations. Donated by their owners, the bodies rest dressed or naked; whole, beheaded or injured; submerged in mud or water; put in coffins or wrapped in plastic; under the shade of a tree or exposed to full sun …
A gathering of ghouls, parasites, and opportunists 
The purpose in all cases is the same: to check how fresh meat decomposes, to study the cadaverous fauna and to decipher how each ghoul visitor is born, lives and dies. And ultimately, answer three key questions in any criminal investigation: how, when and where.
Thanks in part to the bodies from Knoxville, entomologists have identified the different types of arthropods that come to a corpse. First there are the so-called ghoul species , which feed on body tissues; and then the predators appear, attacking the former; and parasites , which take advantage of their larvae and pupae. The feast is also joined by wasps, ants, beetles and other omnivorous species that hunt whatever comes within reach, as well as arthropods that accidentally stumble upon this gastronomic orgy. The latter are occasional visitors of little or no interest to forensic entomologists. But as has already been advanced, this invasion of small people follows patterns that the expert can always advocate, with few exceptions. The studies carried out at the Body Farm reveal that the first to enter the scene are the blue blowflies, which a few minutes after death, attracted by the body odor, invade the natural orifices of the body: the eyes, the nose, the mouth, ears and then the anus and genitals. Wounds inflicted before or at the time of death are also attractive for laying their eggs.
Some foodies that science takes advantage of
The newly hatched larvae feed on fresh meat and complete their metamorphosis in the cadaverous environment. Each phase of its development has been documented by entomologists. In this way, the larval state of any member of the so-called sarcosaprophago community indicates their age and therefore the time elapsed since the death of the victim. But this is not all, since different insects are attracted to different states of decomposition: scientists have described up to eight waves that they call squads or death squads. This nutritional delicacy is also used by entomologists to specify the post-mortem interval and the time of year in which the death occurred. Equipped with his entomological kit, the arthropod expert will be at the scene of the events, to carry out an exhaustive study of the insects that are on the corpse, as well as those that are under it, to rule out the possibility of that has been moved.
Back in the laboratory, the task of preserving the specimens begins: the adults are preserved in an alcoholic solution or pinned; and the immature ones, in the case of larvae, are reared under special conditions to calculate how long it takes them to complete their development. This data, along with others obtained at the crime scene, such as temperature, rainfall and cloudiness, is of great value to specify the post-mortem interval. After conservation, the specialist faces the tedious and difficult task of identifying the specimens and thus establishing their seasonal, geographical and ecological distribution. To their aid comes the science of genetics, as evidenced by an article published last year in the Journal of Forensic Science by entomologist Susan T. Ratcliffe and her colleagues at the University of Illinois. These researchers have developed a simple method based on two genetic techniques – the polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLPs) – which allows the rapid identification of the larvae of 10 different flies belonging to to three families of Diptera. Without a doubt, this is a breakthrough for insect hunters that will speed up the capture of the criminal.
Enrique M. Coperías
