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![Decomposition body scores of pig (Sus scrofa domesticus) carcasses in Palolo Valley, Oahu, Hawaii using the scoring method developed by Keough et al. [30]. Decomposition body scores were generated by carcass region including Head and Neck (a), Trunk (b), and Limbs (c). These scores were them summed to generate a Total Body Score at each PMI (d). Decomposition body scores were generated in real-time (■) and using 2D digital colour photographs. Photograph decomposition scores were generated by observers in the USA (○) and the UK (•) (n observers in each group = 9). Bars represent standard error where n = 9.](profile/Agathe-Ribereau-Gayon/publication/321629582/figure/fig4/AS:574315204706313@1513938823669/Decomposition-body-scores-of-pig-Sus-scrofa-domesticus-carcasses-in-Palolo-Valley.png)
Decomposition body scores of pig (Sus scrofa domesticus) carcasses in Palolo Valley, Oahu, Hawaii using the scoring method developed by Keough et al. [30]. Decomposition body scores were generated by carcass region including Head and Neck (a), Trunk (b), and Limbs (c). These scores were them summed to generate a Total Body Score at each PMI (d). Decomposition body scores were generated in real-time (■) and using 2D digital colour photographs. Photograph decomposition scores were generated by observers in the USA (○) and the UK (•) (n observers in each group = 9). Bars represent standard error where n = 9.
Source publication
In the context of increased scrutiny of the methods in forensic sciences, it is essential to ensure that the approaches used in forensic taphonomy to measure decomposition and estimate the postmortem interval are underpinned by robust evidence-based data. Digital photographs are an important source of documentation in forensic taphonomic investigat...
Contexts in source publication
Context 1
... photograph scores (F 1, 34 = 0.101, p > 0.05). A similar significant impact of PMI on TBS was however observed where photograph scores were con- sistently greater than real-time scores before 30 h postmortem but were then consistently less than real-time scores until the end of the ex- periment at 42 days postmortem (F 16, 544 = 172, p < 0.05) (Fig. ...
Context 2
... varied by PMI where photograph scores were consistently greater than real-time scores before 54 h postmortem but were then consistently less than real- time scores until the end of the experiment at 1008 h postmortem (F 16, 544 = 215, p < 0.05) (Figs. 3 and 4b). Conversely, real-time TBS and body scores generated using Keough et al. method [30] (Fig. 5). Fig. 3. Decomposition body scores of pig (Sus scrofa do- mesticus) carcasses in Palolo Valley, Oahu, Hawaii using the scoring method developed by Megyesi et al. [19]. Decom- position body scores were generated by carcass region in- cluding Head and Neck (a), Trunk (b), and Limbs (c). These scores were them summed to generate a Total ...
Citations
... However, such experimental work on exposed humans is not feasible in many other countries, including Switzerland [15]. Therefore, taphonomic studies on exposed human remains in Europe are often performed retrospectively from medico-legal casework or with various non-human species as substitutes, in particular, domestic pigs (Sus scrofa domesticus) [16][17][18][19][20]. Despite anatomical and physiologic differences between humans and pigs [16,21,22], domestic pigs are often studied as proxies because of their comparable skin, body composition, weight range, physiology, and gut microbiota [16,20,21,[23][24][25]. ...
... For example, they found a pink or red lividity being present in the fresh pig bodies, which is not mentioned for humans in Megyesi et al. [2]. Since the Keough et al. [12] amendments were published, several experimental decomposition studies applied their scoring system [6,7,19,[29][30][31]. However, even with this method, there are limitations for the use of surfacedeposited pig carcasses. ...
... Furthermore, studies have tested whether there are differences between TBS rating by different observers [19,35] and between rating the carcass in real-time versus from photographs [19,36]. They conclude that the inter-observer agreement is high overall for the Megyesi et al. [2] and the Keough et al. [12] methods [19,35,36], and that photographs yield a higher inter-observer agreement than real-time observations [36]. ...
The total body score (TBS) is a visual scoring method to scale the succession of decomposition stages. It compares decomposition between cadavers, to connect it with external taphonomic factors and estimate the post-mortem interval. To study decomposition in various climatic environments, pigs are often used as human proxies. Currently, there is one TBS system by Keough et al. (J Forensic Sci. 2017;62:986) for surface-deposited domestic pigs, coming from South Africa. Our study aims to evaluate this method and analyze porcine decomposition in Central Europe to inform forensic research and casework. We conducted an experiment studying six 50 kg pig carcasses in a temperate Swiss forest. Three observers documented decomposition patterns and rated the decomposition stages from photographs based on the por-cine TBS model by Keough et al. (J Forensic Sci. 2017;62:986). We documented discrepancies between the carcass decomposition of our specimens and those in the South African study, especially related to the high insect activity in our experiment. Furthermore, we noted factors complicating TBS scoring, including rainfall and scavengers. The agreement between TBS observers from photographs was in the highest agreement category apart from one "substantial agreement" category. Our study is the first in Europe to systematically test the Keough et al. (J Forensic Sci. 2017;62:986) method. The results evidence that regional adaptations are required to be applicable for other environments. We present a modified approach based on experimental observations in a Swiss temperate forest. The identification of regional decomposition patterns and drivers will inform future taphonomy research as well as forensic case-work in comparable contexts in Central Europe.
... While digital photographs are a valuable source of documentation in such investigations, their suitability for assessing decomposition, especially in comparison to real-time remains, is a poorly studied aspect, potentially undermining the accuracy of forensic conclusions. In a recent study conducted in a tropical savanna environment in Hawaii [5], researchers aimed to evaluate the suitability of 2D color digital photographs for assessing the decomposition of exposed pig carcasses, which served as human analogs. Two established visual scoring methods, Megyesi et al. [6] and Keough et al. [7], were used to determine the degree of decomposition between 2D images and live decomposition. ...
... While the study conducted by Ribéreau-Gayon et al. [5] demonstrates high inter-observer reproducibility in assessing 2D photographs, this factor mainly addresses the consistency of human interpretation. 3D models, on the other hand, provide objective data that can be analyzed by multiple experts, potentially reducing subjectivity, and enhancing the reliability of forensic assessments. ...
Forensic taphonomy, the study of post-mortem processes, is pivotal in modern forensic science. This short communication illuminates limitations in traditional 2D imaging, specifically digital photographs, within forensic taphonomy, and highlights the vast potential of 3D modeling techniques. Drawing from a recent study in Hawaii’s tropical savanna, we unveil disparities between real-time observations and 2D photographs when assessing decomposition, emphasizing the importance of scoring method selection and the need to scrutinize 2D imaging’s accuracy in forensic taphonomy. Conversely, 3D modeling techniques, an emerging powerhouse in forensic science, offer multidimensional data, including volume, surface area, and spatial relationships, allowing for comprehensive and precise representation of decomposition dynamics. Despite concerns about texture quality, 3D models yield objective data amenable to analysis by multiple experts, thus minimizing subjectivity and augmenting the reliability of forensic assessments. The potential for 3D modeling to bridge the gap between 2D imaging and real-time decomposition requires tailored methodologies. Future research should focus on standardizing protocols and fostering collaboration among forensic experts, technologists, and researchers to unleash 3D technology’s full potential in advancing forensic taphonomy.
... Since, the sample size was small, tests for normal distribution were done using the Shapiro-Wilk test. Inter and intra-rater reliability for TBS scoring was assessed using two-way mixed, consistency, average-measures Intraclass Correlation Coefficient (ICC) as done in previously published studies [61]. Correlations between the degree and rates of skeletonization, ADD values and weather data were all assessed using Pearson's correlation. ...
... A range of decomposition measurements were taken during these studies, but not every measurement was made during every study depending on the decomposition trajectories of the carcasses (Table S1). Individual decomposition studies conducted at this site have been published elsewhere [41,[52][53][54][55] and include detailed descriptions of materials and methods relevant to those studies. ...
... However, carcasses lost approximately 80% of mass by ~230 ADD (9 days). This was not affected by carcass color [53]. Rapid decomposition coincided with the presence of patent fly larval masses throughout the remains and mass loss slowed following their migration by 200 ADD -300 ADD. ...
Decomposition studies have been conducted in several regions of the world, but relatively few have investigated taphonomy in tropical environments. Even fewer have explored carcass decomposition during multiple tropical seasons, leaving the relationships between season and decomposition in tropical environments poorly understood. Ten decomposition studies using 30 carcasses were conducted in Honolulu, Hawaii, USA to start addressing this knowledge gap. These studies show that some postmortem processes were observed regardless of season. Carcass temperature and chemistry were spatiotemporally variable. Fly larval masses were consistently observed within 3 days (∼75 ADD) postmortem and carcasses lost 60%–90% of mass by 10 days (∼250 ADD) postmortem (Total Body Score ∼26). Season had a significant effect on decomposition, yet the warmest and most humid seasons did not always result in the most rapid and extensive decomposition. Seasonal variation appears to be less pronounced than at other tropical decomposition sites.
... The decomposition stages and the associated TBS were assessed on the basis of visual observations and their written description, as well as photographs of the cadavers, which has been shown to be as sufficient as on-site scoring [45,46]. In the open pigs, all 5 possible decomposition stages were observed during the 25 days, which is in line with previous studies [32,47,48]. ...
... Since decomposition correlates with temperature (see Van't Hoffs rule [49]), the use of ADD values allows a better comparison of the speed of the decomposition process between different treatments or studies than just using PMI [42,45,51]. If the TBS of the tent and open cadavers is considered as a function of ADD, the discrepancies in temperature between both treatments become more apparent. ...
The pattern of insect succession and the species composition on cadavers can be influenced by several parameters, one of which is concealment. It has been previously shown for cadavers inside containers (e.g. suitcases or vehicles) or various indoor situations, that concealment can lead to a delayed arrival, altered species composition and decreased number of taxa present at the cadaver. As no data is yet available for the specific environment of tents on these processes, we placed five pig cadavers inside closed two-person tents during the summer of 2021 in a mixed forest in Germany. Five control cadavers were freely accessible for insects. To minimize disturbances, tents were only opened every fifth day over a period of 25 days for estimating the temperature profiles, insect diversity and quantification of the cadavers' decomposition using the total body score (TBS). The temperature inside the tents was only slightly elevated compared to the ambient temperature during the study. Although the tents prevented direct access of adult flies and beetles, the cadavers were colonized because the flies oviposited on the zippers and fly screens of the inner tents. However, the resulting infestation of the cadavers by fly larvae was reduced and delayed, compared to the exposed cadavers. The dominant fly species on both the tent and exposed cadavers was the blow fly Lucilia caesar. Open cadavers showed the expected decomposition patterns with large larval masses. 25 days after placement, only bones and hair remained from the exposed pigs (TBS = 32), while most of the tissue of the cadavers inside the tents was still present (TBS = 22.5) and post feeding larvae were not able to leave the tents. Regarding the attraction of beetles to both treatments, open cadavers were predominately colonized by the silphid Oiceoptoma thoracicum, while the silphid Necrodes littoralis was the most dominant species in the pitfall traps surrounding the tents. Considering the prolonged pre-appearance interval of fly larvae colonizing the cadavers inside tents, the entomological evidence of forensic cases dealing with concealed bodies should be handled with caution, since the post mortem interval might be significantly underestimated.
... TBS approaches are non-invasive, portable, inexpensive, and userfriendly [17]. However, their reliability is influenced by several variables linked with the methodology, the experimental conditions, and the environment considered, all of which may compromise the accuracy of decomposition measurements and PMI estimation [18][19][20][21][22][23]. ...
... In the present study, the donors were deposited at the REST[ES] facility at different times of the year to observe the effects of seasonality on the decomposition processes, and were therefore subject to different weather condi- The longitudinal approach taken with regular monitoring of the donors facilitated the identification of the timings of appearance, duration, and potential disappearance of various taphonomic patterns over the course of decomposition. Digital photographs were collected as previous studies showed their value to evaluate the extent of decomposition of human remains with high inter-observer reproducibility [21,22,25]. A standardized protocol ( Table 2) was developed to maximize photographic coverage of the body and reproducibility of the photographs, as advised in Ribéreau-Gayon et al. [22]. ...
... Digital photographs were collected as previous studies showed their value to evaluate the extent of decomposition of human remains with high inter-observer reproducibility [21,22,25]. A standardized protocol ( Table 2) was developed to maximize photographic coverage of the body and reproducibility of the photographs, as advised in Ribéreau-Gayon et al. [22]. ...
The published literature shows a lack of methods to evaluate the patterns and extent of decomposition of human remains and to estimate the post‐mortem interval (PMI) in humid, continental (Dfb) climates such as Quebec. The aim of this study was to address this gap in the current knowledge base by providing the first observations from human corpses studied under controlled conditions in Quebec. A 12‐month study was conducted at the site for Research in Experimental and Social Thanatology; the first human taphonomy facility in Canada. Six human donors with known time of death were deposited across spring (n = 1), summer (n = 3), and autumn (n = 2) 2021. The lack of suitability of the total body score method to evaluate the extent of decomposition at the facility prompted the development of a new scoring system based on the macromorphoscopic changes observed. The scoring system was applied to the donors to evaluate decomposition throughout seasons. All donors followed comparable decomposition trajectories, regardless of the season of deposition. Eighty‐five percent of taphonomic patterns appeared in the first 25 experimental days or 5000 Kelvin accumulated degree days (350 ADD). Extensive desiccation of tissues was observed at a median of 21 experimental days across donors, resulting in a plateau within decomposition with no extensive skeletonization. To the authors' knowledge, this is the first published report of experimentally observed desiccation in such a form in a Dfb climate. This study provides new data on the types of decomposition patterns to expect in forensic investigations in southern Quebec and comparable climates.
... In such cases, forensic anthropologists may rely on both scene and/or autopsy photographs to accurately estimate the PMI [39]. Although not illustrated through our results, in other studies photographs are considered viable proxies for real-time decomposition rate assessments [39,41,42]. Our results showed that scene photos were made available for only 21 % (36/172) of the cases in our study. ...
The post-mortem interval (PMI) is important in death investigations as it can assist in reconstructing the context of the case and the identification of the unknown individual. However, in some instances the PMI is challenging to estimate due to the absence of regional taphonomy standards. To conduct accurate and locally relevant forensic taphonomy research, investigators require insight into the regional hotspot recovery areas. Thus, forensic cases examined by the Forensic Anthropology Cape Town (FACT) in the Western Cape (WC) province of South Africa between 2006 and 2018 (n = 172 cases; n = 174 individuals) were retrospectively reviewed. In our study, a considerable number of individuals did not have the PMI estimations (31 %; 54/174) and the ability to estimate a PMI was significantly associated with skeletal completeness, unburnt remains, absence of clothing and the absence of entomological evidence (p < 0.05 for each). Significantly fewer cases had the PMI estimated after FACT was formalised in 2014 (p < 0.0001). One third of cases with PMI estimations were made with large open-ended ranges, making them less informative. Factors significantly associated with these broad PMI ranges were fragmented remains, absence of clothing and absence of entomological evidence (p < 0.05 for each). Most decedents (51 %; 87/174) were discovered in police precincts from high crime areas, yet a considerable number (47 %; 81/174) were also found in low crime and sparsely populated areas regularly used for recreational activities. Common sites of body discovery were vegetated areas (23 %; 40/174), followed by the roadside (15 %; 29/174), aquatic environments (11 %; 20/174) and farms (11 %; 19/174). Decedents were discovered exposed (35 %; 62/174), covered with items such as bedding or shrubs (14 %; 25/174) or buried (10 %; 17/174). Our data highlight gaps in forensic taphonomy studies and clearly informs what regional research is needed. Overall, our study demonstrates how forensic case information can inform regional forensic taphonomy studies to locate common areas and contexts for the discovery of decomposed bodies and encourages similar studies in other areas of the world.
... Digital photography is very significant in assisting the investigation as a medium of visual documentation for analysis purposes. A method experiment [24] described digital images as an important documentation source. Its study also used 2D color digital photographs to evaluate the decomposition of exposed human analogs in taphonomy forensic investigations. ...
... All the photos were taken using both reflected infrared and visible light cameras. 20 [24] 24 [4] The paper aims to examine the capabilities of drone-based aerial photography as equipment for recording crime scenes and to test the abilities of 3D models in a forensic context. ...
The use of digital photography medium is dominantly used in the process of investigating criminal cases. Digital photography used in the investigation process is also known as crime scene photography, where photographic images are produced to collect evidence, documenting the scene, and subsequently, be used as a reference for criminal case investigation and prosecution process. Using systematic literature review (SLR), this study identifies the current practice of digital use of photography in the process of investigating criminal cases. Searches via electronic databases of indexed journals, namely, Scopus, Science Direct, Web of Science and Springer were conducted. Data is limited to these journals was produced within the years 2017 until 2021 as the latest research information. The findings consist of 28 papers that had met the criteria by which this study touched on digital photography technology such as DSLR Camera, Drone Photography, and CCTV.
... The TBS method as presented by Megyesi et al. [52] has been assessed in temperate areas, such as South Africa and Hawaii, where the temperatures are relatively consistent throughout the seasons, yielding results that were more consistent than those from geographical regions that experience greater seasonal change [72,73]. For example, in Canada, where there is variable humidity and seasonal temperature extremes, TBS evaluation determined that no human individuals were totally skeletonized in under one year, and tissue rarely mummified [74]. ...
Postmortem interval estimations can be complicated by the inter-individual variation present in human decomposition. Forensic entomologists may especially face challenges interpreting arthropod evidence in scenarios that are not “by the book”, or that vary in unexpected ways. Therefore, it is important to report instances where blow fly colonization does not align with expected soft tissue decomposition as blow fly larvae are often used to produce a time of colonization (TOC) estimation to infer a minimum PMI. We followed the decomposition and blow fly activity of three human donors at the Anthropology Research Facility (University of Tennessee). Delayed oviposition occurred on one donor 115 d post-placement, whereas two donors experienced blow fly re-colonization after cessation of the consumption phase, one 22 d and one more than 200 d after blow fly larvae were last observed. A null hypothesis model tested whether the entomological TOC and anthropological total body score (TBS) estimations encompassed the time of placement (TOP) for each donor. While the null hypothesis was rejected for all TOC estimations, it could not be rejected for the TBS estimations. We discuss how the non-linear nature of human decomposition can pose challenges to interpreting blow fly evidence and suggest that forensic entomology practitioners should recognize these limitations in both research endeavors and applied casework.
... The TBS, TDS and TADS all have high interrater reliability [98,100,[107][108][109]. Most of the methods involve using photographs of decomposing bodies and a study found significant differences when TBS is scored using photographs and when it is scored in the presence of the remains [110]. Moffatt et al. proposed an adjustment to the statistical approach used by Megyesi et al. due to multiple statistical errors [97]. ...
When a capital crime is committed the post-mortem interval (PMI) is of particular importance in investigating a suspect’s alibi in court. A forensic expert can use different methods to estimate the PMI. This research focuses on who is considered an expert in court and whether the methods used to estimate the PMI are reliable. In this study, the methods used to estimate the PMI and the experts consulted, available in Dutch jurisprudence, in the period 2010–2019 were investigated. Ninety-four judicial cases were included and multiple experts and methods of estimating the PMI were found. As part of this study, the methods that were used to estimate the PMI in court were subjected to the Daubert criteria. Of these methods, only the Henssge nomogram and entomological methods met the Daubert criteria. However, the methods are only useful when applied by the right forensic expert and in the right manner. Unfortunately, this was not always the case.
