2002 Entomology - Insect and Corpses
Quelle: International Academy of Forensic Sciences (IAFS), Meeting in Montpellier, France, K-24
Meeting of the IAFS
Entomology - Insects and Corpses
VON M. BENECKE
The organizers asked us to give a short introduction into historic aspects of forensic entomology. In our presentation, we will focus on:
1 - Brief overview over early forensic entomology cases. their main misconceptions and what we might learn from them. This will touch the very modern question of what makes a person a good expert witness, compared 10 a bad one.
2 - Perception of animals related to real, observed decompositions vs. animals of symbolic meaning. Here. we try to differentiale between snakes and maggots in medieval pictures (Dances Of The Dead), as well as mentioning loads and moth. We also show an example where a renaissance artist substituted the heart of a decomposed body (ivory skeleton. Tödlein) by a blowfly.
Furthermore, we present five new unusual cases that we encountered during our forensic entomology co-operations with several police departments in Germany.
1) Mass invasion of spiders and dermestid beetles into flats
Examination of a nearly skeletonized, dried out corpse in the appartment where the person had been living did show masses of dermestid larva skins but nearly no blowfly larvae, pupae, or adults. Reason: An electrical heater dried out the body very quickly so that blowflies did not find a suitable habitat.
In the same house, another (living) person was approached by us. Inside of the flat, hundreds of living spiders and their spider webs were found. Reason: Person refused to use the toilet, or to clean his rooms - excrements attracted large numbers of flies + flies attracted numerous spiders.
2) Maggots in only one eye socket of a dead person
The corpse of a 41-year-old medical doctor was found in his bed. The body was partially dried out; parts of the hip region were skeletonized due to maggot activity. In the facial region of the corpse, blowfly maggots (Lucilia (Phaenicia) serciata [Meigen]) were found exclusively in one eye socket. This is an unusual occurrence since on that side, a bed-light (40 W light bulb) had been burning during the seven week post mortem interval. All other lights in the apartment were switched off and no direct sunlight could enter the space where the body was found (only a TV set had been running all the time, ca. 2 m away from the head at the foot end of the bed). Obviously. the maggots who usually flee light had used up the one eye that was further away from the bedlight as a feeding source. Since the continuing mummification of the corpse led to a substantial restriction of feeding material, the maggots finally switched to the eye that the light was shining on.
3) Maggots in a police dish
During a joint task force operation against 5000 m motorcycle rockers in the federal state Brandenburg, German policemen of another, richer federal state complained for many days about the local food situation. On the last day of the operation, "maggots" were found in the food. We concluded from photographs that (a) the head parts of the alleged maggots were darkened as in beetle or butterfly larvae, and (b) the larvae had been dead (stretched shape). These observations made it likely that the food was neither spoilt nor rotten but that somebody had thrown in the insect larvae on purpose.
4) Credit card fraud and forensic entomology
In November 2000, a decomposed women's corpse was found dead in an appartment in Central Germany. Because the doors were closed, police assumed that the dead person was the tenant. Due to the severerity of decay, the post mortem interval (PMI) of the body could not be determined by regular means. On the other hand, determination of PMl was important since a bank card of the woman had been used, possibly after her dead. On the crime scene, numerous larvae of the „fly of the dead“ (Totenfliege) Cynomyia mortuorum (Linné: family: Calliphoridae R.-D.), were found.
C. mortuorum larvae are known to feed on decomposing animal tissue. In this case, C. mortuorum could outcompete other fly species because of the closed rooms / restricted access. Following Nuorteva (1972, 1977) who found that at 15 to 16,6 °C the delevomental time from egg to adult for C. mortuorum takes at least 26.2 days (max. 31 days), we gave a similar estimation of PMI. It was therefore possible that the bank card was used after the death of the woman, maybe by an innocent relative.
5) Absence of pupae as an indication that a corpse was moved
In a recent investigation, the corpse of a man was found in the trunk of his own car. The body was partially decomposed. Since blood was found on the initial scene of crime, and due to witnesse’s observations, it was expected that the person had been killed several days before in his own car, then stored somewhere, and then was either moved back, or was left all the time in the trunk of the car.
Around one year later, we were asked for an entomological expert opinion. The car was still in police custody, and could therefore be examined. We found that no pupae did enter the gaps between the trunk and the back seats. This was unusual because maggots prefer to pupate in hidden places. Furthermore, the temperature fluctuated heavily at one point so that maggots were expected to hide from the cold, and / or to enter diapause.
Apart from species determination of maggots and pupae that were collected by the police the year before, we delivered the opinion that most likely, the person was colonized by maggots at one point and then stored somewhere until many larvae went into postfeeding, or diapause state. Afterwards, the corpse was moved back into the trunk of the car where only few maggots were left on the corpse. Of those few, none entered the gaps.
This clue became interesting for the police, and the D.A.’s office since now search warrants for suspicous houses could be filed (search for matching pupae).
- Tagung „(Sexuelle) Gewalt und Tötungskriminalität im forensischen Kontext“ des Interdisziplinären Forums Forensik GERMAN TEXT
- V. Curso Internacional de Entomologia Forense GERMAN TEXT
- Interdisziplinäres Fachforum: Der Fall Mirco GERMAN TEXT
- Detection of Semen (Human and Boar) and Saliva on Fabrics by a Very High Powered UV-/VIS-Light Source