1
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Pereira AJ, Breglia GA, Uzal MH. Forensic entomology in homicide cases: study of a corpse found inside a buried vehicle. Forensic Sci Med Pathol 2024:10.1007/s12024-024-00889-2. [PMID: 39230841 DOI: 10.1007/s12024-024-00889-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/26/2024] [Indexed: 09/05/2024]
Abstract
Forensic entomology plays a crucial role in death investigations, particularly in estimating the postmortem interval (PMI). This study presents a forensic entomology case involving a corpse found in a buried utility vehicle. The victim was in an advanced state of decomposition, with autopsy findings revealing gunshot wounds. Cadaveric fauna was collected at the scene and during the autopsy. The analysis revealed a diverse insect community, with predominance of Compsomyiops fulvicrura and Piophila casei. The time of development of species like Dermestes maculatus and Necrobia rufipes was used to estimate the minimum PMI. The presence and low abundance of Calliphora vicina, a species preferring lower temperatures, shed light on the seasonal conditions at the time of death and suggested possible body concealment shortly after death. This research is the first to report insects as evidence in a corpse found in a buried vehicle and contributes to the body of knowledge in forensic entomology. The study also suggests that the use of entomological evidence can provide additional information about the season in which the body was concealed, making it a valuable tool in death investigation and crime scene reconstruction. Finally, it emphasizes the need for proper sampling, expert identification, and close collaboration between forensic entomologists and pathologists.
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Affiliation(s)
- Ana Julia Pereira
- Centro de Investigaciones en Toxicología Ambiental y Agrobiotecnología del Comahue, CITAAC (CONICET, UNCo), Neuquén, Argentina.
| | - Gustavo A Breglia
- Facultad de Medicina, Cátedra de Medicina Legal, Universidad Nacional del Comahue, Cipolletti, Río Negro, Argentina
- Cuerpo de Investigación Forense, Poder Judicial de Río Negro, Río Negro, Argentina
| | - Marcelo H Uzal
- Facultad de Medicina, Cátedra de Medicina Legal, Universidad Nacional del Comahue, Cipolletti, Río Negro, Argentina
- Cuerpo de Investigación Forense, Poder Judicial de Río Negro, Río Negro, Argentina
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2
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Cook DF, Tufail MS, Voss SC. Can the Necrophagous Blow Fly Calliphora vicina (Diptera: Calliphoridae) Be Reared on Plant-Based Meal? INSECTS 2024; 15:551. [PMID: 39057283 PMCID: PMC11276639 DOI: 10.3390/insects15070551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 07/17/2024] [Accepted: 07/18/2024] [Indexed: 07/28/2024]
Abstract
The use of the blow fly Calliphora vicina as a potential pollination species to augment the current reliance on honeybees (Apis mellifera) in Australian horticulture requires knowledge of how best to mass-rear this fly species. Calliphora vicina lays eggs onto carrion soon after death, and the resultant larvae that hatch are necrophagous and feed on the decomposing tissues of the dead animal. Newly hatched larvae of this fly were provided with plant-based meals (soya bean and canola) and compared with larvae provided with livestock-derived meatmeal to determine if plant-based meal could be used to mass-rear this blow fly species. Both soya bean and canola meal media did not support larval survival through to adult emergence. The addition of only 10% whole egg powder to the plant-based meals enabled survival to eclosion of 39% and 13% on soya bean and canola-based media, respectively, compared with 76% on livestock-based meatmeal with 10% whole egg powder. Larvae fed a diet of livestock-based meatmeal with 10% whole dried egg powder had the fastest development to the pupal stage, the highest pupation rate, the heaviest pupae, and the highest subsequent adult eclosion. This study concluded that the use of plant-based meals as a diet for the mass-rearing of the blow fly C. vicina was not a viable option.
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Affiliation(s)
- David F. Cook
- Department of Primary Industries and Regional Development, 3 Baron-Hay Court, South Perth, WA 6161, Australia;
| | - Muhammad Shoaib Tufail
- Department of Primary Industries and Regional Development, 3 Baron-Hay Court, South Perth, WA 6161, Australia;
| | - Sasha C Voss
- School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia;
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3
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Owings CG, McKee-Zech HS, Orebaugh JA, Devlin JL, Vidoli GM. The utility of blow fly (Diptera: Calliphoridae) evidence from burned human remains. Forensic Sci Int 2024; 356:111962. [PMID: 38359753 DOI: 10.1016/j.forsciint.2024.111962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 01/30/2024] [Accepted: 02/05/2024] [Indexed: 02/17/2024]
Abstract
Burning of human remains is a common method to conceal or destroy evidence associated with homicides and illegal activities. However, data regarding blow fly colonization of burned remains are scarce, with all previously published empirical studies focusing only on non-human animals. It is critically important to obtain basic data on blow fly colonization patterns of burned human remains as such evidence may represent the only feasible method for PMI estimation in cases of burning. In this study, we thermally altered six human donors to a Crow-Glassman Scale Level 3 (CGS-3) and placed them at the Anthropology Research Facility at the University of Tennessee in Summer 2021, Spring 2022, and Summer 2022. Six unburned human donors were used as controls. Observations for insect activity began within 24 h of placement and continued twice weekly through decomposition. Age estimations were performed with immature blow flies to estimate the time of colonization (TOC), and accuracy was assessed against the time of placement for each donor. All burned donors examined in this study were colonized by blow flies. No significant difference in species composition was determined between treatments, though TOC estimations from burned donors were slightly (but significantly) less accurate than TOC estimations from unburned donors (80% vs. 83% accuracy; χ2 = 0.041, df = 1, P = 0.840). These results indicate that blow flies can successfully colonize human remains burned to CGS-3 and that accurate TOC estimations can still be generated from larval specimens. Though several limitations to this study exist (e.g., inconsistent donor BMI, lack of donor temperature data), our results underscore the utility of entomological evidence in cases of burned human remains.
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Affiliation(s)
- Charity G Owings
- Department of Entomology and Plant Pathology, University of Tennessee, 2505 EJ Chapman Dr., 370 Plant Biotechnology Building, Knoxville, TN 37996, United States.
| | - Hayden S McKee-Zech
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, United States
| | - Jack A Orebaugh
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, United States
| | - Joanne L Devlin
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, United States
| | - Giovanna M Vidoli
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, United States
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4
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Hartmann K, Bamberg M, Seum S, Amendt J, Verhoff MA, Zehner R. Establishment of a multiplex PCR-CE assay for the simultaneous and rapid analysis of age markers for Calliphora vicina pupae. Int J Legal Med 2024; 138:187-196. [PMID: 37221328 PMCID: PMC10771996 DOI: 10.1007/s00414-023-03013-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 04/14/2023] [Indexed: 05/25/2023]
Abstract
Insects, especially blow flies, are forensically relevant to determine the minimal postmortem interval (PMImin), based on the fact that they are usually the first colonisers of a body. By estimating the age of immature blow flies, interferences can be made about the time since death. Whilst morphological parameters are valuable for age estimation of blow fly larvae, gene expression profiling is more applicable for blow fly pupae. Here, the age-dependent changes in the gene expression levels during the development are analysed. 28 temperature-independent markers have already been described for the age estimation of pupae of the forensically important blow fly Calliphora vicina and are analysed by RT-qPCR. To allow simultaneous analysis of these age markers, a multiplex assay was developed in the present study. After reverse transcription, the markers are analysed simultaneously in an endpoint PCR and subsequently separated by capillary electrophoresis (CE). This method is highly attractive due to its quick and easy procedure and interpretation. The present age prediction tool was adapted and validated. The multiplex PCR assay reproduced the same expression profiles as the RT-qPCR assay based on the same markers. The statistical evaluation shows that the new assay has a lower precision but a better trueness for age determination compared to the RT-qPCR assay. Since the new assay is also qualified to estimate the age of C. vicina pupae and is practical, cost-effective and, even more importantly, time-saving, it is attractive for use in forensic casework.
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Affiliation(s)
- Katharina Hartmann
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt Am Main, Germany.
- Department of Aquatic Ecotoxicology, FB Biowissenschaften, Goethe University, Frankfurt Am Main, Germany.
| | - Malte Bamberg
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt Am Main, Germany
| | - Sandra Seum
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt Am Main, Germany
| | - Jens Amendt
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt Am Main, Germany
| | - Marcel A Verhoff
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt Am Main, Germany
| | - Richard Zehner
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt Am Main, Germany
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Pereira AJ, Centeno ND, Nuñez-Vázquez C. Effects of population variations and temperature on Chrysomya megacephala (Diptera: Calliphoridae) development: implications for estimating the postmortem interval. Int J Legal Med 2024; 138:165-175. [PMID: 37272984 DOI: 10.1007/s00414-023-03020-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 05/12/2023] [Indexed: 06/06/2023]
Abstract
Forensic entomology requires knowledge of the developmental rates of the species that colonize a body after death to estimate the postmortem interval (PMI). These developmental rates may vary depending not only on the species but also on the geographic location due to population differences. Therefore, the objectives of this work were to determine the developmental duration of the forensically important fly Chrysomya megacephala under constant controlled and field condition temperatures and to compare these results, through a meta-analysis, with data reported by other authors on populations from different localities. For this, C. megacephala colonies were established in the laboratory, and the duration of the life cycle was studied at two controlled temperatures (25 °C and 27 °C) and field conditions (27.5 ± 3.2 °C). Analysis of variance was performed to determine differences in developmental time and larval length between constant laboratory temperatures and field conditions. A generalized linear model was performed with predictor variables extracted from the literature (diet, relative humidity, latitude, longitude) to evaluate the effect of population variation on developmental times. The results showed significant differences in developmental times between 25 and 27 °C. As expected, the complete life cycle of C. megacephala was shorter at 27 °C. Finally, the meta-analysis suggested differences between the developmental times of different populations, based on temperature and geographic location. The results of this study provide fundamental developmental data to use C. megacephala in PMI estimations. Finally, we suggest that, when making expert reports, information from local populations should be used to determine a more accurate and reliable PMI.
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Affiliation(s)
- Ana Julia Pereira
- Centro de Investigaciones en Toxicología Ambiental y Agrobiotecnología del Comahue, CITAAC (CONICET, UNCo), Neuquén, Argentina
| | - Néstor Daniel Centeno
- Laboratorio de Entomología Aplicada y Forense, Universidad Nacional de Quilmes, Buenos Aires, Argentina
| | - Carolina Nuñez-Vázquez
- División Entomología, Sociedad Multidisciplinaria en Ciencias Agronómicas y Aplicadas AC, Morelia, México.
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Bambaradeniya TB, Magni PA, Dadour IR. A Summary of Concepts, Procedures and Techniques Used by Forensic Entomologists and Proxies. INSECTS 2023; 14:536. [PMID: 37367352 DOI: 10.3390/insects14060536] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/01/2023] [Accepted: 06/06/2023] [Indexed: 06/28/2023]
Abstract
Forensic entomology is a branch of forensic science that incorporates insects as a part of solving crime. Insect-based evidence recovered at a crime scene can be used to estimate the minimum postmortem interval, determine if a carcass/corpse has been relocated, and contribute to the cause and manner of death. The current review summarises the stepwise usage of forensic entomology methods at a crime scene and in the laboratory, including specimen collection and rearing, identification, xenobiotic detection, documentation, and referencing previous research and casework. It also provides three standards for the collection of insects when attending a crime scene. The Gold standard attributes to a forensic entomologist (FE) who is likely to be well-trained attending a scene. The subsequent standards (Silver and Bronze) have been added because the authors believe that this information is currently missing in the literature. The purpose is so that an attending crime scene agent/proxy with some basic knowledge and some simple tools can recover almost all the insect information required by an FE to make the best estimation of the minimum postmortem interval.
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Affiliation(s)
- Tharindu B Bambaradeniya
- School of Medical, Molecular & Forensic Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - Paola A Magni
- School of Medical, Molecular & Forensic Sciences, Murdoch University, Murdoch, WA 6150, Australia
- Harry Butler Institute, Murdoch University, Murdoch, WA 6150, Australia
| | - Ian R Dadour
- School of Medical, Molecular & Forensic Sciences, Murdoch University, Murdoch, WA 6150, Australia
- Source Certain, P.O. Box 1570, Wangara, WA 6947, Australia
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Thümmel L, Lutz L, Geissenberger J, Pittner S, Heimer J, Amendt J. Decomposition and insect succession of pig cadavers in tents versus outdoors - A preliminary study. Forensic Sci Int 2023; 346:111640. [PMID: 36933523 DOI: 10.1016/j.forsciint.2023.111640] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 03/07/2023] [Accepted: 03/08/2023] [Indexed: 03/12/2023]
Abstract
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.
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Affiliation(s)
- Luise Thümmel
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe-University, Kennedyallee 104, D-60596 Frankfurt am Main, Germany.
| | - Lena Lutz
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe-University, Kennedyallee 104, D-60596 Frankfurt am Main, Germany
| | - Janine Geissenberger
- Department of Environment and Biodiversity, Paris-Lodron University of Salzburg, Hellbrunner Str. 34, A-5020 Salzburg, Austria
| | - Stefan Pittner
- Department of Forensic Medicine, Paris-Lodron University of Salzburg, Ignaz Harrer St. 79, A-5020 Salzburg, Austria
| | - Jonathan Heimer
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, D-48149 Münster, Germany
| | - Jens Amendt
- Institute of Legal Medicine, University Hospital Frankfurt, Goethe-University, Kennedyallee 104, D-60596 Frankfurt am Main, Germany
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8
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Alkhuder K. Attenuated total reflection-Fourier transform infrared spectroscopy: a universal analytical technique with promising applications in forensic analyses. Int J Legal Med 2022; 136:1717-1736. [PMID: 36050421 PMCID: PMC9436726 DOI: 10.1007/s00414-022-02882-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 08/17/2022] [Indexed: 11/25/2022]
Abstract
Contemporary criminal investigations are based on the statements made by the victim and the eyewitnesses. They also rely on the physical evidences found in the crime scene. These evidences, and more particularly biological ones, have a great judicial value in the courtroom. They are usually used to revoke the suspect's allegations and confirm or refute the statements made by the victim and the witnesses. Stains of body fluids are biological evidences highly sought by forensic investigators. In many criminal cases, the success of the investigation relies on the correct identification and classification of these stains. Therefore, the adoption of reliable and accurate forensic analytical methods seems to be of vital importance to attain this objective. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) is a modern and universal analytical technique capable of fingerprint recognition of the analyte using minimal amount of the test sample. The current systematic review aims to through light on the fundamentals of this technique and to illustrate its wide range of applications in forensic investigations. ATR-FTIR is a nondestructive technique which has demonstrated an exceptional efficiency in detecting, identifying and discriminating between stains of various types of body fluids usually encountered in crime scenes. The ATR-FTIR spectral data generated from bloodstains can be used to deduce a wealth of information related to the donor species, age, gender, and race. These data can also be exploited to discriminate between stains of different types of bloods including menstrual and peripheral bloods. In addition, ATR-FTIR has a great utility in the postmortem investigations. More particularly, in estimating the postmortem interval and diagnosing death caused by extreme weather conditions. It is also useful in diagnosing some ambiguous death causes such as fatal anaphylactic shock and diabetic ketoacidosis.
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Affiliation(s)
- Khaled Alkhuder
- Division of Microbial Disease, UCL Eastman Dental Institute, University College London, 256 Gray's Inn Road, London, WC1X 8LD, UK.
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Owings CG, McKee-Zech HS, Schwing ST, Bugajski KN, Davis MC, Steadman DW. Not by the Book: Observations of Delayed Oviposition and Re-Colonization of Human Remains by Blow Flies. INSECTS 2022; 13:879. [PMID: 36292827 PMCID: PMC9604324 DOI: 10.3390/insects13100879] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
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.
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Affiliation(s)
- Charity G. Owings
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, USA
| | - Hayden S. McKee-Zech
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, USA
| | - Sarah T. Schwing
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, USA
| | - Kristi N. Bugajski
- Department of Biology, Valparaiso University, 1610 Campus Drive East, Valparaiso, IN 46383, USA
| | - Mary C. Davis
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, USA
| | - Dawnie W. Steadman
- Department of Anthropology, University of Tennessee, 1621 Cumberland Ave., Knoxville, TN 37996, USA
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10
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Entomological identification of the post-mortem colonization of wolf cadavers in different decomposition stages. Sci Justice 2022; 62:520-529. [DOI: 10.1016/j.scijus.2022.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 06/06/2022] [Accepted: 07/18/2022] [Indexed: 11/19/2022]
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Chappell TM, Rusch TW, Tarone AM. A Fly in the Ointment: How to Predict Environmentally Driven Phenology of an Organism That Partially Regulates Its Microclimate. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.837732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Phenological models representing physiological and behavioral processes of organisms are used to study, predict, and optimize management of ecological subsystems. One application of phenological models is the prediction of temporal intervals associated with the measurable physiological development of arthropods, for the purpose of estimating future time points of interest such as the emergence of adults, or estimating past time points such as the arrival of ovipositing females to new resources. The second of these applications is of particular use in the conduct of forensic investigations, where the time of a suspicious death must be estimated on the basis of evidence, including arthropods with measurable size/age, found at the death scene. Because of the longstanding practice of using necrophagous insects to estimate time of death, standardized data and methods exist. We noticed a pattern in forensic entomological validation studies: bias in the values of a model parameter is associated with improved model fit to data, for a reason that is inconsistent with how the models used in this practice are interpreted. We hypothesized that biased estimates for a threshold parameter, representing the lowest temperature at which insect development is expected to occur, result in models’ accounting for behavioral and physiological thermoregulation but in a way that results in low predictive reliability and narrowed applicability of models involving these biased parameter estimates. We explored a more realistic way to incorporate thermoregulation into insect phenology models with forensic entomology as use context, and found that doing so results in improved and more robust predictive models of insect phenology.
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Abdullah SR, Shafie MS, Wahid SA. Forensically important fly larvae on floating corpses in Malaysia: three case reports. EGYPTIAN JOURNAL OF FORENSIC SCIENCES 2022. [DOI: 10.1186/s41935-022-00275-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Understanding how environmental conditions can influence the insect distribution on corpses is essential to determine the postmortem interval. However, literatures related to forensically important flies in an aquatic environment were scarce. We report herewith a case series comprising three forensic cases related to floating corpses infested with fly larvae in Kuala Lumpur, Malaysia.
Case presentation
Case 1 involved the corpse of a 43-year old male found in the waterside of an abandoned mine. Case 2 was a 40-year-old male floating on a river stream, while case 3 was an 11-year-old boy who was found trapped in a monsoon drain after heavy rain. Numerous larvae of various stages, identified as Chrysomya megacephala (Calliphoridae) species, were collected in all cases even though the number of larvae was relatively lower compared to those usually collected on corpses found on terrestrial areas. Besides, the larvae of Eristalis spp. (Syrphidae), which are known to be exclusively associated with water bodies, were found in two of the cases. The blowfly Ch. rufifacies (Calliphoridae) larvae were collected only in case 3.
Conclusions
These findings show that both Ch. megacephala and Ch. rufifacies can be found in the ecologically varied death scene habitats including aquatic areas. Meanwhile, the presence of Eristalis spp. can be used as an indicator of death location associated with an aquatic environment. The challenges and limitations of analyzing entomological evidence on bodies discovered in aquatic environments were also discussed.
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13
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Dowling SN, Skaggs CL, Owings CG, Moctar K, Picard CJ, Manicke NE. Insects as Chemical Sensors: Detection of Chemical Warfare Agent Simulants and Hydrolysis Products in the Blow Fly Using LC-MS/MS. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3535-3543. [PMID: 35188758 DOI: 10.1021/acs.est.1c07381] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this work, blow flies were investigated as environmental chemical sample collectors following a chemical warfare attack (CWA). Blow flies sample the environment as they search for water and food sources and can be trapped from kilometers away using baited traps. Three species of blow flies were exposed to CWA simulants to determine the persistence and detectability of these compounds under varying environmental conditions. A liquid chromatography mass spectrometry (LC-MS/MS) method was developed to detect CWA simulants and hydrolysis products from fly guts. Flies were exposed to the CWA simulants dimethyl methylphosphonate and diethyl phosphoramidate as well as the pesticide dichlorvos, followed by treatment-dependent temperature and humidity conditions. Flies were sacrificed at intervals within a 14 day postexposure period. Fly guts were extracted and analyzed with the LC-MS/MS method. The amount of CWA simulant in fly guts decreased with time following exposure but were detectable 14 days following exposure, giving a long window of detectability. In addition to the analysis of CWA simulants, isopropyl methylphosphonic acid, the hydrolysis product of sarin, was also detected in blow flies 14 days post exposure. This work demonstrates the potential to obtain valuable samples from remote or access-restricted areas without risking lives.
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Affiliation(s)
- Sarah N Dowling
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Christine L Skaggs
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Charity G Owings
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
- Department of Anthropology, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Khadija Moctar
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Christine J Picard
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Nicholas E Manicke
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
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Hildebrand CS, Cervenka VJ, Moon RD, Thomson RE. Calliphoridae (Diptera) on Decomposing Pig Carcasses and Human Cadavers in the Upper Midwest of North America. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:129-134. [PMID: 34564729 DOI: 10.1093/jme/tjab163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Indexed: 06/13/2023]
Abstract
The geographic ranges of forensically informative taxa on decomposing remains vary across regions. To determine which calliphorid flies would be expected to occur in Minnesota and the upper Midwest, individual freshly killed pig carcasses (Sus scrofa L.) were placed in the field in St. Paul, MN, at monthly intervals from May to October 2017 and May to September 2018. Aerial nets, forceps, and pitfall traps were used to collect and preserve associated adult and immature insects. Sixty-four forensically informative insect taxa were recorded, representing three insect orders and 14 families. Ten informative calliphorid species were recorded on carcasses, adding four new Minnesota records. Comparison of species lists from 26 human forensic cases indicated agreement between the two lists, except for Lucilia coeruleiviridis Macquart, Calliphora vomitoria (L.), and Cynomya cadaverina Robineau-Desvoidy, which occurred on pig carcasses but not human remains, and Calliphora livida Hall, which occurred on human remains, but not carcasses. The composite fauna list from cadavers agreed largely with the 2-yr list from pig carcasses.
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Affiliation(s)
- Correy S Hildebrand
- Department of Entomology, University of Minnesota, 1980 Folwell Avenue, 219 Hodson Hall, St. Paul, MN 55108, USA
| | | | - Roger D Moon
- Department of Entomology, University of Minnesota, 1980 Folwell Avenue, 219 Hodson Hall, St. Paul, MN 55108, USA
| | - Robin E Thomson
- Department of Entomology, University of Minnesota, 1980 Folwell Avenue, 219 Hodson Hall, St. Paul, MN 55108, USA
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15
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Age-dependent gene expression of Calliphora vicina pupae (Diptera: Calliphoridae) at constant and fluctuating temperatures. Int J Legal Med 2021; 135:2625-2635. [PMID: 34570269 PMCID: PMC8523437 DOI: 10.1007/s00414-021-02704-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 09/13/2021] [Indexed: 11/10/2022]
Abstract
Estimating the age of the developmental stages of the blow fly Calliphora vicina (Diptera: Calliphoridae) is of forensic relevance for the determination of the minimum post-mortem interval (PMImin). Fly eggs and larvae can be aged using anatomical and morphological characters and their modification during development. However, such methods can only hardly be applied for aging fly pupae. Previous study described age estimation of C. vicina pupae using gene expression, but just when reared at constant temperatures, but fluctuating temperatures represent a more realistic scenario at a crime scene. Therefore, age-dependent gene expression of C. vicina pupae were compared at 3 fluctuating and 3 constant temperatures, the latter representing the mean values of the fluctuating profiles. The chosen marker genes showed uniform expression patterns during metamorphosis of C. vicina pupae bred at different temperature conditions (constant or fluctuating) but the same mean temperature (e.g. constant 10 °C vs. fluctuating 5–15 °C). We present an R-based statistical tool, which enables estimation of the age of the examined pupa based on the analysed gene expression data.
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16
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Jales JT, Barbosa TM, Soares VP, Gama RA. Effect of Terbufos (Organophosphate) on the Cadaveric Colonization Process: Implications for Postmortem Interval Calculation. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:1056-1063. [PMID: 33558871 DOI: 10.1093/jme/tjaa284] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Indexed: 06/12/2023]
Abstract
The determination of necrophagous fly specie's development time is considered an accurate method for estimating postmortem interval (PMI). However, pesticides and other chemicals can alter the flies' life cycle, inducing errors in PMI estimation. Thus, this work aimed to evaluate the effect of different doses of Terbufos (Organophosphates) on the temporal dispersion pattern and development of immature dipterans associated with decaying rat carcasses. For this, 150 g female Wistar rats received, via gavage, 200 µl of Terbufos (5 or 10 mg/kg) or distilled water (control) and, after 30 min of administration, the animals were euthanized and distributed in suspended traps to decompose under environmental conditions. The dispersing immatures were collected daily, and their development time was monitored until the emergence of adult flies. After data analysis, it was observed that Terbufos altered 1) the temporal pattern of larval dispersion; 2) the composition and structure of the colonizing assemblage (emerged adults); 3) species' development time, accelerating or delaying their cycle, depending on the dose used; and 4) the califorids and sarcophagids emergence rate, increasing the mortality of pupae from intoxicated carcasses. Thus, this work demonstrates experimentally that Terbufos directly influences the development of flies with forensic potential and discusses the implications for PMI estimation, which can assist in future investigative processes with suspected poisoning by this organophosphate.
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Affiliation(s)
- J T Jales
- Laboratory of Insect and Vectors, Department of Microbiology and Parasitology, Federal University of Rio Grande do Norte, Av. Sen. Salgado Filho, Lagoa Nova, Natal, RN, Brazil
| | - T M Barbosa
- Laboratory of Insect and Vectors, Department of Microbiology and Parasitology, Federal University of Rio Grande do Norte, Av. Sen. Salgado Filho, Lagoa Nova, Natal, RN, Brazil
| | - V P Soares
- Department of Biophysics and Pharmacology, Federal University of Rio Grande do Norte, Av. Sen. Salgado Filho, Lagoa Nova, Natal, RN, Brazil
| | - R A Gama
- Laboratory of Insect and Vectors, Department of Microbiology and Parasitology, Federal University of Rio Grande do Norte, Av. Sen. Salgado Filho, Lagoa Nova, Natal, RN, Brazil
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17
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Komo L, Hedouin V, Charabidze D. Benefits of heterospecific aggregation on necromass: influence of temperature, group density, and composition on fitness-related traits. INSECT SCIENCE 2021; 28:144-152. [PMID: 32067410 DOI: 10.1111/1744-7917.12766] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/19/2020] [Accepted: 02/12/2020] [Indexed: 06/10/2023]
Abstract
Necrophagous blowflies (Diptera: Calliphoridae) such as Calliphora vicina, a cold-tolerant species, and Lucilia sericata, a warm-adapted species, are pioneer carrion-breeder. Although these two species have different temperature preferences, larvae aggregate actively and often feed simultaneously on carrion. The hypothesis to be tested was that L. sericata benefits from the association with C. vicina at lower temperatures (i.e., 15 °C) and that C. vicina derives greater benefits from this association at higher temperatures (i.e., 28 °C). Therefore, both species were raised at these two constant temperatures from first instars to adults under three different conditions: monospecific low-density, monospecific high-density, and heterospecific high-density. The time until larval migration, surface area of puparia, and survival rates were determined for each condition. Differences between these fitness-related traits were found between species, temperatures, group densities, and species compositions. At 28 °C, C. vicina larvae bred in heterospecific groups migrated significantly earlier and in higher numbers than that under same density conspecific conditions, with a lower mortality rate. At 15 °C, both species benefited from high-density heterospecific associations, expressed by faster development and larger puparia. In conclusion, necrophagous larvae benefited from heterospecific aggregations at suboptimal temperatures by adapting their migration time to that of the faster species. Since temperature changes throughout the day and over the year, the beneficiary of such a collective association also changes. The costs involved and deviations to the temperature-size rule highlight the complexity of the carrion ecosystem.
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Affiliation(s)
- Larissa Komo
- CHU Lille, EA 7367-UTML-Unite de Taphonomie Medico-Legale, University of Lille, Lille, 59000, France
| | - Valéry Hedouin
- CHU Lille, EA 7367-UTML-Unite de Taphonomie Medico-Legale, University of Lille, Lille, 59000, France
| | - Damien Charabidze
- CHU Lille, EA 7367-UTML-Unite de Taphonomie Medico-Legale, University of Lille, Lille, 59000, France
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18
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Faris AM, West WR, Tomberlin JK, Tarone AM. Field Validation of a Development Data Set for Cochliomyia macellaria (Diptera: Calliphoridae): Estimating Insect Age Based on Development Stage. JOURNAL OF MEDICAL ENTOMOLOGY 2020; 57:39-49. [PMID: 31576404 DOI: 10.1093/jme/tjz156] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Indexed: 06/10/2023]
Abstract
Insect age estimates can be useful for estimating the postmortem interval when certain assumptions are met. Such estimates are based on species-specific development data that are temperature-dependent and variable, and therefore prone to different degrees of error depending on the combination of data sets, calculations, and assumptions applied in a specific instance. Because of this potential error, validating the methods employed is necessary for determining accuracy and precision of a given technique. For forensic entomology, validation of development data sets is one approach for identifying the uncertainty associated with insect age estimates. Cochliomyia macellaria (Fabricius) is a primary colonizer of remains across the United States and is commonly encountered in forensic investigations. A development study for this species was produced for a central Texas, U.S. population; the variation associated with this data set and the pre-appearance interval were previously explored in an ecological model. The objectives of this study were to determine the accuracy of the development data and the validity of the ecological model when applied to immatures of known age developing under field conditions. Results indicate this data set is an accurate predictor of insect age when using development stage, supporting the validity of the ecological model in central Texas. Age predictions made with all stages present in a sample were more accurate than predictions made with the most developed stage in a sample, and estimates of age when using the prepupal stage were overestimated regardless of prediction method, though thermal requirements for total development were similar.
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Affiliation(s)
- A M Faris
- Department of Entomology, Texas A&M University, TX
| | - W R West
- Department of Entomology, Texas A&M University, TX
| | | | - A M Tarone
- Department of Entomology, Texas A&M University, TX
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19
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Hu G, Wang Y, Sun Y, Zhang Y, Wang M, Wang J. Development of Chrysomya rufifacies (Diptera: Calliphoridae) at Constant Temperatures Within its Colony Range in Yangtze River Delta Region of China. JOURNAL OF MEDICAL ENTOMOLOGY 2019; 56:1215-1224. [PMID: 31329911 DOI: 10.1093/jme/tjz052] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Indexed: 06/10/2023]
Abstract
The age of insects found on corpses is often used to estimate the minimum postmortem interval by forensic entomologists. Insect development is affected by biotic and abiotic factors, and temperature is the most important environmental factor that determines the length of insect development. Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) is a globally distributed fly that is commonly found on corpses, and this study investigated the development of C. rufifacies from China at various constant temperatures. At 16, 19, 22, 25, 28, 31, and 34°C, the developmental time from egg to adult was 870.17 ± 11.50, 566.20 ± 8.79, 406.38 ± 10.98, 291.14 ± 4.71, 232.59 ± 5.96, 192.47 ± 3.45, and 160.48 ± 7.15 h, respectively. We established three developmental models for C. rufifacies to estimate the age of the developing insect: the isomorphen diagram model, the isomegalen diagram model and the thermal summation model. Regression analysis was conducted to obtain the relationship between body length and development time of the larvae from hatching to wandering. The developmental threshold temperatures of the egg, 1st instar, 2nd instar, 3rd instar, and wandering larvae, and intra-puparial stages were 12.28 ± 0.30, 11.74 ± 0.95, 12.70 ± 0.55, 11.68 ± 0.96, 10.53 ± 1.53, and 12.51 ± 0.41°C, respectively. The developmental threshold temperature, and the thermal summation constant during the entire developmental period were 3759.95 ± 170.80 degree hours and 11.96 ± 0.38°C, respectively. This study provides an improved dataset to estimate the postmortem interval of corpses using C. rufifacies.
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Affiliation(s)
- Guoliang Hu
- Department of Forensic Medicine, Soochow University, Suzhou, China
| | - Yu Wang
- Department of Forensic Medicine, Soochow University, Suzhou, China
| | - Yong Sun
- Criminal Police Branch, Yancheng Public Security Bureau, Yancheng, China
| | - Yingna Zhang
- Department of Forensic Medicine, Soochow University, Suzhou, China
| | - Man Wang
- Department of Forensic Medicine, Soochow University, Suzhou, China
| | - Jiangfeng Wang
- Department of Forensic Medicine, Soochow University, Suzhou, China
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20
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VanLaerhoven SL, Merritt RW. 50 years later, insect evidence overturns Canada's most notorious case - Regina v. Steven Truscott. Forensic Sci Int 2019; 301:326-330. [PMID: 31202145 DOI: 10.1016/j.forsciint.2019.04.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 04/24/2019] [Accepted: 04/25/2019] [Indexed: 10/26/2022]
Abstract
On 11 June 1959, the body of 12-year old Lynne Harper was discovered in a woodlot northeast of Clinton, Ontario. Although insect evidence was photographed and collected at the scene and autopsy, this evidence was not used in the 1959 trial. Instead, time of death was pinpointed to a 45-min window of 1900-1945 h on 9 June 1959 based on stomach content analysis. Based on circumstantial evidence and this time frame that he was the last suspect to see her alive, 14-year old Steven Truscott was convicted of her murder. He was scheduled to be hanged, but a temporary reprieve postponed his execution. In 1960, his death sentence was commuted to life imprisonment. Truscott was the youngest person to be sentenced to death in Canada, and his case provided the major impetus toward abolition of the death penalty in Canada. Truscott always maintained his innocence. In 2001, the Association in Defence of the Wrongly Convicted filed an appeal to have the case reopened. In 2006, the authors of this paper were contacted by Attorneys James Lockyer and Phil Campbell of the LCP Law Firm in Toronto to investigate this case. Fresh evidence was presented at the Ontario Court of Appeal in 2006-2007 including testimony of 3 forensic entomologists. This resulted in controversy regarding identification of the insects and assumptions of insect behaviour that affected the postmortem interval estimate. Lack of scientific evidence for the controversial theories proposed by one testifying entomologist resulted in disregarding his testimony. Instead, testimony by VanLaerhoven and Merritt was accepted. Based on their analysis and a re-creation experiment of the insect evidence, initial fly colonization occurred during daylight hours of 10 June 1959. The collected larvae were not likely to have been deposited on the body before dark (2140 h) on 9 June 1959 as this would have resulted in significantly larger and more advanced larval instar than were collected at the scene or autopsy. This analysis, together with a pathology reanalysis of stomach content analysis, demonstrated that the original estimate of time of death was unreliable. Truscott was with numerous witnesses prior to 1900 h and after 2000 h on 9 June 1959, thus the estimate of time of death was the most critical evidence in the original 1959 trial and the 2006-2007 appeal. On 28 August 2007, his conviction was overturned, declared a wrongful conviction and miscarriage of justice. Steven Truscott was acquitted of the murder charges.
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Affiliation(s)
- S L VanLaerhoven
- Department of Biology, University of Windsor, Windsor, ON N9B 3P4, Canada.
| | - R W Merritt
- Department of Entomology, Michigan State University, East Lansing, MI 48824, United States
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21
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The maggot, the ethologist and the forensic entomologist: Sociality and thermoregulation in necrophagous larvae. J Adv Res 2018; 16:67-73. [PMID: 30899590 PMCID: PMC6413306 DOI: 10.1016/j.jare.2018.12.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/03/2018] [Accepted: 12/05/2018] [Indexed: 11/24/2022] Open
Abstract
Necrophagous blowflies larvae maintain a permanent balance between thermal regulation and aggregation. These two parameters affect their development. Such a behavioral regulation likely optimize their development on carcasses. This may be a pre-social strategy to cope with harsh environment. Forensic entomology studies should consider the behavior of maggots.
Necrophagous insects are mostly known through forensic entomology. Indeed, experimental data investigating the effect of temperature on larval development underlies post-mortem interval estimations. However, such developmental studies rarely considered the behavior of maggots. In contrast, previous results supposed that calliphoridae larvae use behavioral strategies to optimize their development on carcasses. To test this idea, we analyzed the trade-off between thermal regulation (individual thermal preferences) and social behavior (aggregation) in Lucilia sericata larvae. The first set of experiments analyzed the behavior of third instars in response to thermal changes in their environment. The results demonstrated a clear thermoregulation behavior, supporting the assumption that larvae continuously move to reach a suitable internal temperature. The second set of experiments focused on the trade-off between thermal optimization and aggregation. The results showed a constant search for congeners and an attractiveness of aggregates, sometimes to the detriment of thermal optimization. Together, these results demonstrate a balance between behavioral thermoregulation and social strategies, two significant mechanisms for developmental optimization in necrophagous larvae. In conclusion, these findings highlights unexpected (social) strategies to cope with ephemeral resource and high selection pressure. They also raise important questions for forensic entomology.
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22
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Gemmellaro MD, Bucolo C, Musumeci E, Hamilton GC, Weidner LM. First Observations of Initial Blow Fly (Diptera: Calliphoridae) Activity on Lava Fields and in Subterranean Environments in Sicily in Cool Temperatures. JOURNAL OF MEDICAL ENTOMOLOGY 2018; 55:1622-1626. [PMID: 29982764 DOI: 10.1093/jme/tjy099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Indexed: 06/08/2023]
Abstract
In criminal cases involving the recovery of human remains, as well as in cases of myiasis and pest management, the expertise of a forensic entomologist has been requested more and more frequently in Sicily. Recently, research on the insect species of forensic interest in Sicily has been investigated. The aim of this research was to raise awareness of this discipline and to build a Sicilian entomofauna checklist during cool temperatures. The predominant species observed in this study was Calliphora vicina (Robineau-Desvoidy) (Diptera, Calliphoridae), the first to colonize the carcasses; Lucilia spp. (Diptera, Calliphoridae) were also present. We wanted to explore the potential insect activity on decaying matter both on lava fields, exposed to sunlight, and in dark subterraneous environments. No activity was observed in our dark environment for 20 d; then, C. vicina was observed on one of the carcasses, laying eggs in complete darkness at a temperature of 6.4°C. Larval development under these conditions was delayed and the mortality rate was high. This preliminary trial allowed us to improve our experimental design and helped map new sites where we can expand our research to collect new data on insect distribution and their activity in caves.
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Affiliation(s)
- Maria Denise Gemmellaro
- Department of Entomology, Rutgers University, The State University of New Jersey, New Brunswick, NJ
- Gruppo Grotte Catania del Club Alpino Italiano Sezione dell 'Etna, Via Messina, Catania, Italy
| | - Carmelo Bucolo
- Gruppo Grotte Catania del Club Alpino Italiano Sezione dell 'Etna, Via Messina, Catania, Italy
| | - Elisa Musumeci
- Gruppo Grotte Catania del Club Alpino Italiano Sezione dell 'Etna, Via Messina, Catania, Italy
| | - George C Hamilton
- Department of Entomology, Rutgers University, The State University of New Jersey, New Brunswick, NJ
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23
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Feddern N, Amendt J, Schyma C, Jackowski C, Tschui J. A preliminary study about the spatiotemporal distribution of forensically important blow flies (Diptera: Calliphoridae) in the area of Bern, Switzerland. Forensic Sci Int 2018; 289:57-66. [DOI: 10.1016/j.forsciint.2018.05.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 05/06/2018] [Accepted: 05/14/2018] [Indexed: 11/25/2022]
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24
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Temperature: the weak point of forensic entomology. Int J Legal Med 2018; 133:633-639. [PMID: 30043225 DOI: 10.1007/s00414-018-1898-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/17/2018] [Indexed: 10/28/2022]
Abstract
Measuring temperature is a key factor in forensic entomology. While noting factors to consider for a posteriori temperature estimation, many studies lack detailed methods or general rules allowing their integration into insect development-time calculations. This article proposes tools for determining the adequacy of weather station temperature datasets versus the local temperature experienced by carrion breeders. The idea is to start from a local scale (i.e., the cadaver) and gradually move to larger scales: at each step, the temperature can be increased, decreased or smoothed by environmental or biological factors. While a one-size-fits-all solution is not feasible for a complex and sensitive issue such as forensic meteorology, this checklist increases the reliability of minimum post-mortem interval (PMImin) estimation and the traceability of the proposed assumption.
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25
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Thermal conditions in selected urban and semi-natural habitats, important for the forensic entomology. Forensic Sci Int 2018; 287:153-162. [PMID: 29665482 DOI: 10.1016/j.forsciint.2018.03.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 03/24/2018] [Accepted: 03/26/2018] [Indexed: 11/24/2022]
Abstract
A long-term study on thermal conditions in selected urban and semi-natural habitats, where human corpses are likely to be found, was conducted in the city of Lodz (Central Poland). Thermal data were collected during two years at nine sites and compared with corresponding data from the nearest permanent meteorological station at Lodz Airport (ICAO code: EPLL). The conditions closest to those at the meteorological station prevailed in the deciduous forest, coefficient of determination R2 for those sets of data was above 0.96. The open field was characterized by high daily amplitudes, especially during spring, while the site in the allotment gardens was characterized by relatively high winter temperatures. The conditions prevailing in all closed space sites were very diverse and only slightly similar to the external ones. The most distinct site was an unheated basement in a tenement house, where temperature was almost always above 0°C and daily amplitudes were negligible.
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26
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Salimi M, Rassi Y, Oshaghi M, Chatrabgoun O, Limoee M, Rafizadeh S. Temperature requirements for the growth of immature stages of blowflies species, Chrysomya albiceps and Calliphora vicina, (Diptera:Calliphoridae) under laboratory conditions. EGYPTIAN JOURNAL OF FORENSIC SCIENCES 2018. [DOI: 10.1186/s41935-018-0060-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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27
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Zajac BK, Amendt J, Verhoff MA, Zehner R. Dating Pupae of the Blow Fly Calliphora vicina Robineau-Desvoidy 1830 (Diptera: Calliphoridae) for Post Mortem Interval-Estimation: Validation of Molecular Age Markers. Genes (Basel) 2018; 9:E153. [PMID: 29522463 PMCID: PMC5867874 DOI: 10.3390/genes9030153] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/04/2018] [Accepted: 03/05/2018] [Indexed: 12/24/2022] Open
Abstract
Determining the age of juvenile blow flies is one of the key tasks of forensic entomology when providing evidence for the minimum post mortem interval. While the age determination of blow fly larvae is well established using morphological parameters, the current study focuses on molecular methods for estimating the age of blow flies during the metamorphosis in the pupal stage, which lasts about half the total juvenile development. It has already been demonstrated in several studies that the intraspecific variance in expression of so far used genes in blow flies is often too high to assign a certain expression level to a distinct age, leading to an inaccurate prediction. To overcome this problem, we previously identified new markers, which show a very sharp age dependent expression course during pupal development of the forensically-important blow fly Calliphora vicina Robineau-Desvoidy 1830 (Diptera: Calliphoridae) by analyzing massive parallel sequencing (MPS) generated transcriptome data. We initially designed and validated two quantitative polymerase chain reaction (qPCR) assays for each of 15 defined pupal ages representing a daily progress during the total pupal development if grown at 17 °C. We also investigated whether the performance of these assays is affected by the ambient temperature, when rearing pupae of C. vicina at three different constant temperatures-namely 17 °C, 20 °C and 25 °C. A temperature dependency of the performance could not be observed, except for one marker. Hence, for each of the defined development landmarks, we can present gene expression profiles of one to two markers defining the mentioned progress in development.
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Affiliation(s)
- Barbara K Zajac
- Institute of Legal Medicine, Goethe University, 60596 Frankfurt, Germany.
| | - Jens Amendt
- Institute of Legal Medicine, Goethe University, 60596 Frankfurt, Germany.
| | - Marcel A Verhoff
- Institute of Legal Medicine, Goethe University, 60596 Frankfurt, Germany.
| | - Richard Zehner
- Institute of Legal Medicine, Goethe University, 60596 Frankfurt, Germany.
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28
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Communication in necrophagous Diptera larvae: interspecific effect of cues left behind by maggots and implications in their aggregation. Sci Rep 2018; 8:2844. [PMID: 29434278 PMCID: PMC5809460 DOI: 10.1038/s41598-018-21316-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 02/02/2018] [Indexed: 11/08/2022] Open
Abstract
Necrophagous Calliphoridae breed in vertebrate carrion. Their larvae aggregate and form large masses of individuals. These aggregated larvae can reach adulthood faster than scattered larvae, increasing their chances of survival. Furthermore, the gathering of larvae of different species suggests possible interspecific aggregation vectors. In this context, the effect of larval ground-left cues on larvae of Calliphora vomitoria and Lucilia sericata was studied. We used video tracking to follow larvae placed in binary choice tests. We observed (1) a preference of both species for a side marked by conspecific or heterospecific larvae compared to an unmarked side, (2) a preference of L. sericata larvae for a conspecific-marked side compared to a heterospecific-marked side but only at high concentration of cues and (3) a preference of both species for the side marked by the greater number of larvae. These results demonstrate that larvae leave a mark locally which is retentive, has an interspecific range, has an effect proportional to its intensity and whose strength varies depending on the emitting species. According to the self-organization theory, this mark could enhance larval gathering and promote interspecific aggregations. While not yet demonstrated, an interspecific Allee effect could explain the interspecific association of necrophagous calliphorid larvae.
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29
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McGarry J, Ratsep E, Ressel L, Leeming G, Ricci E, Verin R, Blundell R, Kipar A, Hetzel U, Yeates J. Introducing forensic entomology in cases of suspected animal neglect. Vet Rec 2018; 182:139. [DOI: 10.1136/vr.104158] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 06/29/2017] [Accepted: 11/24/2017] [Indexed: 11/04/2022]
Affiliation(s)
- John McGarry
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
| | - Emily Ratsep
- Department of Pathobiology; Ontario Veterinary College, University of Guelph; Guelph Ontario Canada
| | - Lorenzo Ressel
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
| | - Gail Leeming
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
| | - Emanuele Ricci
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
| | - Ranieri Verin
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
| | - Richard Blundell
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
| | - Anja Kipar
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
- Institute of Veterinary Pathology; Vetsuisse Faculty; University of Zurich; Zurich Switzerland
| | - Udo Hetzel
- Institute of Veterinary Science, University of Liverpool; Liverpool UK
- Institute of Veterinary Pathology; Vetsuisse Faculty; University of Zurich; Zurich Switzerland
| | - James Yeates
- Royal society of the Protection of Cruelty to Animals; Redhill UK
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30
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Archer MS, Jones SD, Wallman JF. Delayed reception of live blowfly ( Calliphora vicina and Chrysomya rufifacies) larval samples: implications for minimum postmortem interval estimates. Forensic Sci Res 2017; 3:27-39. [PMID: 30483649 PMCID: PMC6197129 DOI: 10.1080/20961790.2017.1408550] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 11/21/2017] [Indexed: 11/25/2022] Open
Abstract
Forensic entomology evidence collected by police and mortuary staff may be delayed in getting to the entomologist. Live samples may continue developing and alter minimum postmortem interval (PMImin) estimates. This study investigated development of simulated evidential samples of Calliphora vicina Robineau-Desvoidy and Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) maggots. Maggots of each species were studied in three developmental classes: “small” (late second/early third instar), “mid” (mid third instar) and “large” (late third instar). Seven replicates of 11 maggots in each class were assigned without food to four treatments: (1) 24 h at 20 °C; (2) 24 h at 4 °C; (3) 48 h at 20 °C and (4) 48 h at 4 °C. There was a significant difference in absolute length change across treatments, reflecting size for C. vicina, and interaction between size, time and temperature for Ch. rufifacies. Calliphora vicina maggots showed minimal mortality, and most second instar larvae moulted by the experiment's end. Chrysomya rufifacies showed heavy mortality and minimal moulting from the second to third instar. Only “large” Ch. rufifacies maggots kept at room temperature for 48 h pupariated. Since these results confirm that development can continue in live unfed maggot samples after their collection, it is not advisable to delay their preservation.
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Affiliation(s)
- Melanie S Archer
- Department of Forensic Medicine, Monash University/Victorian Institute of Forensic Medicine, Southbank, Australia
| | - Stephanie D Jones
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Wollongong, Australia
| | - James F Wallman
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Wollongong, Australia
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Cervantès L, Dourel L, Gaudry E, Pasquerault T, Vincent B. Effect of low temperature in the development cycle of Lucilia sericata (Meigen) (Diptera, Calliphoridae): implications for the minimum postmortem interval estimation. Forensic Sci Res 2017; 3:52-59. [PMID: 30483651 PMCID: PMC6197139 DOI: 10.1080/20961790.2017.1406839] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 11/15/2017] [Indexed: 11/01/2022] Open
Abstract
Knowledge of necrophagous insects' developmental data is necessary for the forensic entomologist to estimate a reliable minimum postmortem interval (PMImin). Among the most represented necrophagous species, Lucilia sericata (Diptera, Calliphoridae) is particularly interesting. It is regularly identified in samples, with a predominance in summer, and is commonly used by analysts of our entomology department (Institut de Recherche Criminelle de la Gendarmerie Nationale) to estimate the PMImin with the accumulated degree days (ADD) method. This method requires the mathematical lower thermal threshold to be known. This value dictates the quality of the applied ADD method but cannot be considered as fixed, especially when insect development occurs at temperatures close to the biological threshold. In such conditions, it is necessary to study the influence of such temperatures on development rate, as well as the consequences of estimating the period of first oviposition on cadavers, when using the ADD method. Seven replicate rearings were conducted at six different temperatures: 30 °C, 24 °C, 18 °C, 15 °C, 12 °C and 10 °C. Time of development and time of emergence were recorded. The effect of low temperature on the development cycle and the reliability of the ADD method under this entire temperature spectrum were studied using different linear regression models. Calculated durations of total insect time development and experimental rearing duration were then compared. A global linear model cannot be used on the whole temperature spectrum experienced by L. sericata without resulting in an overestimation at some temperatures. We found a combination of two linear regression models to be suitable for the estimation of the total development time, depending on the temperature experienced by L. sericata. This approach allowed us to obtain a variation lower than 2% at 12 °C and 10 °C between the calculated duration and experimental duration of development. In comparison, the results obtained with a global model show a variation higher than 3% at 12 °C and 10% at 10 °C.
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Affiliation(s)
- Laetitia Cervantès
- Forensic Fauna Flora Department, Institut de Recherche Criminelle De La Gendarmerie nationale, Cergy Pontoise Cedex, France
| | - Laurent Dourel
- Forensic Fauna Flora Department, Institut de Recherche Criminelle De La Gendarmerie nationale, Cergy Pontoise Cedex, France
| | - Emmanuel Gaudry
- Forensic Fauna Flora Department, Institut de Recherche Criminelle De La Gendarmerie nationale, Cergy Pontoise Cedex, France
| | - Thierry Pasquerault
- Forensic Fauna Flora Department, Institut de Recherche Criminelle De La Gendarmerie nationale, Cergy Pontoise Cedex, France
| | - Benoît Vincent
- Forensic Fauna Flora Department, Institut de Recherche Criminelle De La Gendarmerie nationale, Cergy Pontoise Cedex, France
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32
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Pacheco VA, Hans KR, VanLaerhoven SL. The Relationship Between Surface Area and Volume of Common Blow Fly (Diptera: Calliphoridae) Oviposition Sites and Carrion Body Mass. JOURNAL OF MEDICAL ENTOMOLOGY 2017; 54:1278-1284. [PMID: 28535281 DOI: 10.1093/jme/tjx108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Indexed: 06/07/2023]
Abstract
Female blow flies (Diptera: Calliphoridae) demonstrate site preferences when ovipositing on carrion. Preference for oviposition sites is believed to reflect the suitability of the site such that the most preferred locations provide offspring with the greatest chance of survival. A number of factors might influence female choice, including area available for oviposition. For species known to aggregate during oviposition, the surface area of oviposition sites may be a key factor in the decision-making process. Using ImageJ, the surface area or volume of eight common oviposition sites on 13 fetal pig (Sus scrofa domesticus L.) carcasses was measured. Regression analysis was used to determine if body mass could predict the area or volume available for oviposition. We observed significant positive relationships between size of oviposition sites and body mass for all eight oviposition sites. The strongest relationships were observed for the face (R2 = 0.86) and legs (R2 = 0.84). To test the predictive capacity of this relationship, a blind validation study was performed. Five pigs of various body masses were randomly selected, and the available space of the eight sites was estimated using the regression equations. The validation study confirmed that the regression equations for most oviposition sites demonstrated their predictive capacity based on 95% prediction intervals. This research provides a tool that can be used to correct for differences in oviposition site area or volume between carcasses of varying mass so that researchers may gain a greater understanding of the oviposition preferences and aggregation behaviors in future studies.
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Affiliation(s)
- V A Pacheco
- Department of Biology, University of Windsor, 401 Sunset Ave., Windsor, ON N9B 3P4, Canada
| | - K R Hans
- Department of Biology, University of Windsor, 401 Sunset Ave., Windsor, ON N9B 3P4, Canada
- Department of Biology, Delaware State University, 1200 N. DuPont Hwy, Dover, DE 19901
| | - S L VanLaerhoven
- Department of Biology, University of Windsor, 401 Sunset Ave., Windsor, ON N9B 3P4, Canada
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33
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Weidner LM, Gemmellaro MD, Tomberlin JK, Hamilton GC. Evaluation of bait traps as a means to predict initial blow fly (Diptera: Calliphoridae) communities associated with decomposing swine remains in New Jersey, USA. Forensic Sci Int 2017; 278:95-100. [DOI: 10.1016/j.forsciint.2017.06.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 06/05/2017] [Accepted: 06/11/2017] [Indexed: 11/15/2022]
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34
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Ody H, Bulling MT, Barnes KM. Effects of environmental temperature on oviposition behavior in three blow fly species of forensic importance. Forensic Sci Int 2017; 275:138-143. [PMID: 28364721 DOI: 10.1016/j.forsciint.2017.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 03/03/2017] [Accepted: 03/07/2017] [Indexed: 10/20/2022]
Abstract
A number of factors are known to affect blow fly behavior with respect to oviposition. Current research indicates that temperature is the most significant factor. However temperature thresholds for oviposition in forensically important blow flies have not been well studied. Here, the oviposition behavior of three species of forensically important blow fly species (Calliphora vicina, Calliphora vomitoria and Lucilia sericata,) was studied under controlled laboratory conditions over a range of temperatures (10-40°C). Lower temperature thresholds for oviposition of 16°C and 17.5°C were established for C. vomitoria and L. sericata respectively, whilst C. vicina continued to lay eggs at 10°C. C. vomitoria and L. sericata both continued to lay eggs at 40°C, whilst the highest temperature at which oviposition occurred in C. vicina was 35°C. Within these thresholds there was considerable variation in the number of surviving pupae, with a general pattern of a single peak within the range of temperatures at which eggs were laid, but with the pattern being much less distinct for L. sericata.
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Affiliation(s)
- Helen Ody
- Department of Natural Sciences, University of Derby, Kedleston Road DE22 1HE, UK
| | - Mark T Bulling
- Department of Natural Sciences, University of Derby, Kedleston Road DE22 1HE, UK
| | - Kate M Barnes
- Department of Natural Sciences, University of Derby, Kedleston Road DE22 1HE, UK.
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35
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Gruner SV, Slone DH, Capinera JL, Turco MP. Development of the Oriental Latrine Fly, Chrysomya megacephala (Diptera: Calliphoridae), at Five Constant Temperatures. JOURNAL OF MEDICAL ENTOMOLOGY 2017; 54:290-298. [PMID: 27816915 DOI: 10.1093/jme/tjw169] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 09/18/2016] [Indexed: 06/06/2023]
Abstract
Chrysomya megacephala (Fabricius) is a forensically important fly that is found throughout the tropics and subtropics. We calculated the accumulated development time and transition points for each life stage from eclosion to adult emergence at five constant temperatures: 15, 20, 25, 30, and 35 °C. For each transition, the 10th, 50th, and 90th percentiles were calculated with a logistic linear model. The mean transition times and % survivorship were determined directly from the raw laboratory data. Development times of C. megacephala were compared with that of two other closely related species, Chrysomya rufifacies (Macquart) and Phormia regina (Meigen). Ambient and larval mass temperatures were collected from field studies conducted from 2001-2004. Field study data indicated that adult fly activity was reduced at lower ambient temperatures, but once a larval mass was established, heat generation occurred. These development times and durations can be used for estimation of a postmortem interval (PMI).
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Affiliation(s)
- S V Gruner
- Department of Entomology and Nematology, University of Florida, 1881 Natural Area Dr., Gainesville, FL 32611 (; )
| | - D H Slone
- U.S. Geological Survey, Wetland and Aquatic Research Center, 7920 NW 71st Street, Gainesville, FL 32653
| | - J L Capinera
- Department of Entomology and Nematology, University of Florida, 1881 Natural Area Dr., Gainesville, FL 32611 (; )
| | - M P Turco
- Division of Herpetology, Florida Museum of Natural History, University of Florida, Gainesville, FL 32611
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36
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Boulay J, Deneubourg JL, Hédouin V, Charabidzé D. Interspecific shared collective decision-making in two forensically important species. Proc Biol Sci 2017; 283:rspb.2015.2676. [PMID: 26865296 DOI: 10.1098/rspb.2015.2676] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To date, the study of collective behaviour has mainly focused on intraspecific situations: the collective decision-making of mixed-species groups involving interspecific aggregation-segregation has received little attention. Here, we show that, in both conspecific and heterospecific groups, the larvae of two species (Lucilia sericata and Calliphora vomitoria, calliphorid carrion-feeding flies) were able to make a collective choice. In all groups, the choice was made within a few minutes and persisted throughout the period of the experiment. The monitoring of a focal individual within a group showed that these aggregations were governed by attractive and retentive effects of the group. Furthermore, the similarity observed between the conspecific and heterospecific groups suggested the existence of shared aggregation signals. The group size was found to have a stronger influence than the species of necrophagous larvae. These results should be viewed in relation to the well-known correlation between group size and heat generation. This study provides the first experimental examination of the dynamics of collective decision-making in mixed-species groups of invertebrates, contributing to our understanding of the cooperation-competition phenomenon in animal social groups.
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Affiliation(s)
- Julien Boulay
- CHU Lille, Université Lille 2, EA 7367-UTML-Unité de Taphonomie Médico-Légale, Lille, France Unit of Social Ecology-CP 231, Université Libre de Bruxelles (ULB), Campus Plaine, Boulevard du Triomphe, Building NO-level 5, 1050 Bruxelles, Belgium
| | - Jean-Louis Deneubourg
- Unit of Social Ecology-CP 231, Université Libre de Bruxelles (ULB), Campus Plaine, Boulevard du Triomphe, Building NO-level 5, 1050 Bruxelles, Belgium
| | - Valéry Hédouin
- CHU Lille, Université Lille 2, EA 7367-UTML-Unité de Taphonomie Médico-Légale, Lille, France
| | - Damien Charabidzé
- CHU Lille, Université Lille 2, EA 7367-UTML-Unité de Taphonomie Médico-Légale, Lille, France
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37
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Niederegger S, Steube X, Tiltmann P, Mall G. Decomposition rate of intact and injured piglet cadavers. Rechtsmedizin (Berl) 2016. [DOI: 10.1007/s00194-016-0137-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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38
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Hofer IMJ, Hart AJ, Martín-Vega D, Hall MJR. Optimising crime scene temperature collection for forensic entomology casework. Forensic Sci Int 2016; 270:129-138. [PMID: 27940072 DOI: 10.1016/j.forsciint.2016.11.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 10/18/2016] [Accepted: 11/09/2016] [Indexed: 11/29/2022]
Abstract
The value of minimum post-mortem interval (minPMI) estimations in suspicious death investigations from insect evidence using temperature modelling is indisputable. In order to investigate the reliability of the collected temperature data used for modelling minPMI, it is necessary to study the effects of data logger location on the accuracy and precision of measurements. Digital data logging devices are the most commonly used temperature measuring devices in forensic entomology, however, the relationship between ambient temperatures (measured by loggers) and body temperatures has been little studied. The placement of loggers in this study in three locations (two outdoors, one indoors) had measurable effects when compared with actual body temperature measurements (simulated with pig heads), some more significant than others depending on season, exposure to the environment and logger location. Overall, the study demonstrated the complexity of the question of optimal logger placement at a crime scene and the potential impact of inaccurate temperature data on minPMI estimations, showing the importance of further research in this area and development of a standard protocol. Initial recommendations are provided for data logger placement (within a Stevenson Screen where practical), situations to avoid (e.g. placement of logger in front of windows when measuring indoor temperatures), and a baseline for further research into producing standard guidelines for logger placement, to increase the accuracy of minPMI estimations and, thereby, the reliability of forensic entomology evidence in court.
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Affiliation(s)
- Ines M J Hofer
- Department of Pharmacy and Forensic Science, King's College London, 150 Stamford Street, London SE1 9NH, United Kingdom.
| | - Andrew J Hart
- Forensic Services, Metropolitan Police Service, 109 Lambeth Road, London SE1 7LP, United Kingdom.
| | - Daniel Martín-Vega
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom.
| | - Martin J R Hall
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom.
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39
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Bernhardt V, Schomerus C, Verhoff MA, Amendt J. Of pigs and men—comparing the development of Calliphora vicina (Diptera: Calliphoridae) on human and porcine tissue. Int J Legal Med 2016; 131:847-853. [DOI: 10.1007/s00414-016-1487-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 10/20/2016] [Indexed: 12/11/2022]
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40
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Moffatt C, Simmons T, Lynch-Aird J. An Improved Equation for TBS and ADD: Establishing a Reliable Postmortem Interval Framework for Casework and Experimental Studies. J Forensic Sci 2016; 61 Suppl 1:S201-7. [PMID: 26293169 DOI: 10.1111/1556-4029.12931] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 02/02/2015] [Accepted: 02/09/2015] [Indexed: 12/31/2022]
Abstract
Megyesi et al.'s (J Forensic Sci, 2005, 50, 618) paper was important to forensic anthropology as it introduced a quantitative framework for estimating time since death in human cadavers, based upon physical appearance by way of scoring on a novel scale. However, errors concerning rounding, temperature scale, and incorrect use of a statistical regression model render their predictive formula unusable. Based upon only their more reliable data, a more appropriate regression model to predict accumulated degree days (ADD) from total body score (TBS) is presented. The new model is also a superior fit (r(2) = 0.91) and produces markedly narrower confidence intervals than the original, which also allowed impossible, negative ADD values. Explanations of the shortcomings in the original analysis and calculations are presented, which it is hoped will help forensic scientists avoid making similar mistakes.
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Affiliation(s)
- Colin Moffatt
- School of Forensic and Applied Sciences, University of Central Lancashire, Preston, PR1 2HE, UK.,Department of Natural Science and Public Health, Zayed University, Dubai, Box 19282, UAE
| | - Tal Simmons
- Department of Forensic Science, Virginia Commonwealth University, Richmond, VA, 23284, USA
| | - Jeanne Lynch-Aird
- School of Forensic and Applied Sciences, University of Central Lancashire, Preston, PR1 2HE, UK
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41
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The distribution of blow fly (Diptera: Calliphoridae) larval lengths and its implications for estimating post mortem intervals. Int J Legal Med 2015; 130:287-97. [DOI: 10.1007/s00414-015-1289-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 11/04/2015] [Indexed: 10/22/2022]
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42
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Chirino MG, Rossi LF, Bressa MJ, Luaces JP, Merani MS. Comparative study of mitotic chromosomes in two blowflies, Luciliasericata and L.cluvia (Diptera, Calliphoridae), by C- and G-like banding patterns and rRNA loci, and implications for karyotype evolution. COMPARATIVE CYTOGENETICS 2015; 9:103-18. [PMID: 25893078 PMCID: PMC4387384 DOI: 10.3897/compcytogen.v9i1.8671] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 12/22/2014] [Indexed: 05/27/2023]
Abstract
The karyotypes of Luciliacluvia (Walker, 1849) and Luciliasericata (Meigen, 1826) from Argentina were characterized using conventional staining and the C- and G-like banding techniques. Besides, nucleolus organizer regions (NORs) were detected by fluorescent in situ hybridization (FISH) and silver staining technique. The chromosome complement of these species comprises five pairs of autosomes and a pair of sex chromosomes (XX/XY, female/male). The autosomes of both species have the same size and morphology, as well as C- and G-like banding patterns. The X and Y chromosomes of Luciliacluvia are subtelocentric and easily identified due to their very small size. In Luciliasericata, the X chromosome is metacentric and the largest of the complement, showing a secondary constriction in its short arm, whereas the Y is submetacentric and smaller than the X. The C-banding patterns reflect differences in chromatin structure and composition between the subtelocentric X and Y chromosomes of Luciliacluvia and the biarmed sex chromosomes of Luciliasericata. These differences in the sex chromosomes may be due to distinct amounts of constitutive heterochromatin. In Luciliacluvia, the NORs are placed at one end of the long-X and of the long-Y chromosome arms, whereas one of the NORs is disposed in the secondary constriction of the short-X chromosome arm and the other on the long-Y chromosome arm in Luciliasericata. Although the G-like banding technique does not yield G-bands like those in mammalian chromosomes, it shows a high degree chromosomal homology in both species because each pair of autosomes was correctly paired. This chromosome similarity suggests the absence of autosomal rearrangements during karyotype evolution in the two species studied.
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Affiliation(s)
- Mónica G. Chirino
- Instituto de Ecología, Genética y Evolución de Buenos Aires, Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Ciudad Autónoma de Buenos Aires, Argentina
- Laboratorio de Biología Cromosómica, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, C1121ABG Ciudad Autónoma de Buenos Aires, Argentina
| | - Luis F. Rossi
- Laboratorio de Biología Cromosómica, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, C1121ABG Ciudad Autónoma de Buenos Aires, Argentina
| | - María J. Bressa
- Instituto de Ecología, Genética y Evolución de Buenos Aires, Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Ciudad Autónoma de Buenos Aires, Argentina
| | - Juan P. Luaces
- Laboratorio de Biología Cromosómica, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, C1121ABG Ciudad Autónoma de Buenos Aires, Argentina
| | - María S. Merani
- Laboratorio de Biología Cromosómica, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, C1121ABG Ciudad Autónoma de Buenos Aires, Argentina
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43
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Sharma R, Kumar Garg R, Gaur J. Various methods for the estimation of the post mortem interval from Calliphoridae: A review. EGYPTIAN JOURNAL OF FORENSIC SCIENCES 2015. [DOI: 10.1016/j.ejfs.2013.04.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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44
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Baqué M, Filmann N, Verhoff MA, Amendt J. Establishment of developmental charts for the larvae of the blow fly Calliphora vicina using quantile regression. Forensic Sci Int 2015; 248:1-9. [DOI: 10.1016/j.forsciint.2014.12.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 11/27/2014] [Accepted: 12/18/2014] [Indexed: 10/24/2022]
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45
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Rapid discrimination of maggots utilising ATR-FTIR spectroscopy. Forensic Sci Int 2015; 249:189-96. [PMID: 25703014 DOI: 10.1016/j.forsciint.2015.01.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 12/01/2014] [Accepted: 01/28/2015] [Indexed: 11/20/2022]
Abstract
Entomological evidence is used in forensic investigations to indicate time since death. The species and age of maggots or flies that are present at the scene can be used when estimating how much time has passed since death. Current methods that are used to identify species and developmental stage of larvae and fly samples are highly subjective, costly and often time consuming processes and require the expertise of an entomologist or species identification via DNA analysis. The use of vibrational spectroscopy, as an alternative identification method, would allow for a quicker, cheaper and less subjective technique and would allow entomological evidence to be used more commonly in the forensic process. This proof of principle study shows the potential for using attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) as a rapid tool for differentiating between various species of larvae, such as those commonly found at crime scenes. The proposed regime would provide a rapid and valuable tool resulting in reduced time for both species identification and life cycle determination, particularly in forensic situations.
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46
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Calculating time since death in a mock crime case comparing a new computational method (ExLAC) with the ADH method. Forensic Sci Int 2015; 248:78-81. [PMID: 25598485 DOI: 10.1016/j.forsciint.2014.12.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 12/04/2014] [Accepted: 12/24/2014] [Indexed: 11/22/2022]
Abstract
We compared the results of calculating a minimum post-mortem interval (PMImin) in a mock crime case using two different methods: accumulated degree hours (ADH method) and a newly developed computational model called ExLAC. For the ADH method we further applied five reference datasets for the development time of Calliphora vicina (Diptera: Calliphoridae) from 5 different countries and our results confirmed the following: (1) Reference data for blowfly development that has not been sampled using a local blowfly colony should not, in most circumstances, be used in estimating a PMI in real cases; and (2) The new method ExLAC might be a potential alternative to the ADH method.
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47
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Terrestrial laser scanning to model sunlight irradiance on cadavers under conditions of natural decomposition. Int J Legal Med 2014; 128:725-32. [DOI: 10.1007/s00414-014-1013-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 04/22/2014] [Indexed: 11/26/2022]
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Gruner SV, Slone DH. A fresh liver agar substrate for rearing small numbers of forensically important blow flies (Diptera: Calliphoridae). JOURNAL OF MEDICAL ENTOMOLOGY 2014; 51:713-715. [PMID: 24897867 DOI: 10.1603/me13070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Forensically important calliphorids can be reared on a mixture of beef liver and agar. Small pieces of meat, especially fresh or frozen beef liver, will desiccate in 2-6 h, but this simple-to-make feeding substrate remains moist for at least 12 h at 25 and 30 degrees C without desiccation, even in small (5 g) amounts. We determined the survivorship of small numbers of Chrysomya megacephala (F.) (first-instar larvae to adult eclosion) raised on 5 g of liver agar and fresh beef liver. We found that all larvae raised on 5 g of liver died due to desiccation, but survivorship on 5 g of liver agar was equivalent to that on larger (50 g) pieces of either liver agar or beef liver.
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Heaton V, Moffatt C, Simmons T. Quantifying the Temperature of Maggot Masses and its Relationship to Decomposition. J Forensic Sci 2014; 59:676-82. [DOI: 10.1111/1556-4029.12396] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 03/19/2013] [Accepted: 04/07/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Vivienne Heaton
- School of Forensic and Investigative Sciences; University of Central Lancashire; Preston PR1 2HE U.K
| | - Colin Moffatt
- School of Forensic and Investigative Sciences; University of Central Lancashire; Preston PR1 2HE U.K
| | - Tal Simmons
- School of Forensic and Investigative Sciences; University of Central Lancashire; Preston PR1 2HE U.K
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Lü Z, Zhai X, Zhou H, Li P, Ma J, Guan L, Mo Y. Effects of Ketamine on the Development of forensically important BlowflyChrysomya megacephala(F.) (Diptera: Calliphoridae) and its Forensic Relevance. J Forensic Sci 2014; 59:991-6. [DOI: 10.1111/1556-4029.12430] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 05/23/2013] [Accepted: 06/01/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Zhou Lü
- Forensic Medicine Institute; Henan University of Science and Technology; No. 31 Anhui Road Jianxi District Luoyang Henan 471003 China
| | - Xiandun Zhai
- Forensic Medicine Institute; Henan University of Science and Technology; No. 31 Anhui Road Jianxi District Luoyang Henan 471003 China
| | - Haimei Zhou
- Forensic Medicine Institute; Henan University of Science and Technology; No. 31 Anhui Road Jianxi District Luoyang Henan 471003 China
| | - Pu Li
- Forensic Medicine Institute; Henan University of Science and Technology; No. 31 Anhui Road Jianxi District Luoyang Henan 471003 China
| | - Jinqi Ma
- Forensic Medicine Institute; Henan University of Science and Technology; No. 31 Anhui Road Jianxi District Luoyang Henan 471003 China
| | - Ling Guan
- Forensic Medicine Institute; Henan University of Science and Technology; No. 31 Anhui Road Jianxi District Luoyang Henan 471003 China
| | - Yaonan Mo
- Forensic Medicine Institute; Henan University of Science and Technology; No. 31 Anhui Road Jianxi District Luoyang Henan 471003 China
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