Comparative Performance and Complementarity of Four Sampling Methods and Arthropod Preference Tests from Human and Porcine Remains at the Forensic Anthropology Center in Knoxville, Tennessee

Abstract

Comparative performance and complementarity tests of four arthropod sampling methods (aerial netting, hand collection, pitfall traps, and sticky traps), used by forensic entomologists in death investigations, training workshops, and research trials, were conducted from simultaneously placed human and porcine subjects inside the Forensic Anthropology Center at the University of Tennessee, Knoxville, TN. A secondary aim investigated the widely held claim that pig carcasses are reliable surrogates for human corpses. Over a 35-d period in summer 1989, >72,000 invertebrates from three subjects (one human, two pigs) were sampled of which 93% were members of the forensically important (FI) fauna. Performance tests revealed that hand collections, when performed by an experienced forensic entomologist, consistently yielded the largest fraction of FI arthropods from the total invertebrate catch, followed by aerial netting, sticky traps, and pitfall traps, regardless of subject. Pitfall traps and hand collections were broadly effective at sampling both fly and beetle populations, whereas aerial netting and sticky traps mostly targeted flies. The best two-method combination, based on the highest combined catches of FI taxa, were hand collections and pitfall traps, regardless of subject. Between-subject comparisons revealed negligible preference by FI arthropods for human over pig remains. Insofar as our limited comparisons allow with only three study subjects, these results validated the concept of transferability of "best practices" from one subject to another and confirmed the claim that pig carcasses (of 23-27-kg starting mass) can substitute for human corpses in research and training programs, at least for summer-exposed and unconcealed remains in the first 5 wk postmortem.

Postmortem succession of gut microbial communities in deceased human subjects

“…Since all individuals were decomposing at the same time in relatively close proximity, insect activity was comparable between them. While a comprehensive survey of arthropod communities was not included as a part of this study, we did observe extensive activity by Calliphoridae larvae, as has been previously documented at this facility (Schoenly et al, 2007). …”

Enhanced Characterization of the Smell of Death by Comprehensive Two-Dimensional Gas Chromatography-Time-of-Flight Mass Spectrometry (GCxGC-TOFMS)

“…Domestic pig ( Sus scrofa domesticus L.) (25 kg) was used to surrogate human models mainly for physiological, biochemical, ethical, legal and economic reasons [25], [40]–[45]. Unlike other animals, pigs are considered to be an acceptable substitute due to their similarity to humans in body mass (torso in weight), skin structure, fat to muscle ratio and hair coverage [5], [25], [45]–[46].…”

“…Unlike other animals, pigs are considered to be an acceptable substitute due to their similarity to humans in body mass (torso in weight), skin structure, fat to muscle ratio and hair coverage [5], [25], [45]–[46]. The greatest dissimilarity between pigs and humans are the bones, which have a different microstructure [46]–[47].…”

Cuticular Hydrocarbons: A New Tool in Forensic Entomology?

“…Significant work using human cadavers has been conducted at the Anthropological Research Facility of the University of Tennessee at Knoxville. Among these are the early work by Rodriguez (1986) specifically looking at insect activity associated with decomposing bodies and later work by Schoenly et al [23]. As early as 1989, the domestic pig was suggested as being a standard surrogate for humans in decomposition studies and this was reinforced by work by Schoenly et al [23].…”