A geometric morphometric analysis of wing variations in shape and size of the blue bottle fly, Calliphora vicina (Diptera: Calliphoridae).

A geometric morphometric analysis was performed on the right wing of adult Calliphora vicina (Robineau-Desvoidy) collected across 4 altitudinal levels in Sicily. The objective of this study was to assess differences in shape and centroid size (CS) between females and males and across elevations. The wings analyzed in this study were removed from adults of C. vicina collected with baited traps at 20, 700, 1,153, and 1,552; for this study, 19 landmarks were identified in each wing. The coordinates of the landmarks were aligned and superimposed to prevent variations due to position, orientation, and scale; they were then scaled to the same CS and recentered. CS and Procrustes differences were, respectively, used to assess variations in size and shape. Significant differences were observed in wing shape between males and females but not between all altitudinal levels. Female wings were found to be significantly larger than males (P < 0.01). Wings of flies collected at the highest altitudinal level resulted in significantly larger wings than those collected at lower altitudes (P < 0.001), with CS values ranging from 12.1 to 14.1. Variation in wing shape can impact thermal regulation, and therefore, oxygen content, temperature, atmospheric pressure, and solar radiation can have an effect on an insect's body and activity levels. At high elevations and lower temperatures, larger wings could mean less energy expenditure when flying to increase body temperature.

Transnational comparison of the impact of COVID-19 on medicolegal death investigations and the administration of justice: Early stages of the pandemic.

COVID-19 has had an unprecedented impact on arguably every sector of our criminal justice system. To assess the impact that this global health crisis has had on our medicolegal investigations and administration of justice during the early stages of the pandemic, this research aims to give voice to the lived experiences of medicolegal death investigators (coroners, medical examiners and pathologists). This research involved in-depth interviews and follow-ups with experienced personnel from Canada (3), Italy (1), the United Kingdom (1) and the United States (4). Results suggest that despite facing similar challenges, each individual office has had to develop their own strategies to overcome obstacles during the early stages of the pandemic. These results help identify overlapping areas for constructive policy and procedural changes, including recommendations for workflow adaptations, strategic partnerships and other approaches to best prepare for subsequent health crises.

COVID-19 and British Columbia's volunteer search and rescue workers: risk recognition and risk mitigation.

Background: Early during COVID-19, British Columbia coordinated collaboration between academic researchers, public healthcare systems, and private sector partners to focus research resources on knowledge gaps in a timely manner, avoid duplication, and identify overlooked aspects. At a collaboration symposium, it became evident that BC's volunteer search & rescue (SAR) cadre was overlooked. Objective: Our exploratory project studied volunteer SAR's operational readiness; use and perceived value of information sources; consistency in infection prevention measures among volunteer stations, and with their professional counterparts for comparable first aid medical interventions throughout the pandemic. Methods: We partnered with the 2 organizations that govern BC's volunteer SAR stations. Local station leaders completed a short confidential survey. Guidance documents issued by associations governing voluntary and professional first responders were compared. Results: Survey responses were received from 33 of 109 local stations, spanning all regions of BC. Most remained operationally ready throughout the entire pandemic (12.1% had to stand down at times). Except for 21% lacking eye protection, all had personal protective equipment commensurate with that of healthcare professionals; however, few used this PPE in a manner consistent with professional counterparts. Usage and perceived usefulness of various information sources differed. There was no communication link between the province's infection control experts and 2 volunteer SAR organizations. Conclusions: Search & rescue capability was maintained despite pandemic impacts. Results reveal strengths and opportunities for improvement in the ways volunteers are informed and protected. Infection control experts providing advice for emergency health services professional responders should remember to include their volunteer counterparts.

The Forensic Entomology Case Report-A Global Perspective.

Forensic practitioners analyzing entomological evidence are faced with numerous challenges when presenting their findings to law practitioners, particularly in terms of terminology used to describe insect age, what this means for colonization time of remains, and the limitations to estimates made. Due to varying legal requirements in different countries, there is no standard format for the entomological case report prepared, nor any guidelines as to the sections that are required, optional or unnecessary in a case report. The authors herein propose sections that should be considered when drafting an entomological case report. The criteria under which entomological evidence is analyzed are discussed, as well as the limitations for each criterion. The concept of a global, standardized entomological case report is impossible to achieve due to national legislative differences, but the authors here propose a basic template which can be adapted and changed according to the needs of the practitioner. Furthermore, while the discussion is fairly detailed, capturing all differences between nations could not be accomplished, and those initiating casework for the first time are encouraged to engage other practicing forensic entomologists or professional associations within their own nation or region, to ensure a complete report is generated that meets lab or national requirements, prior to generating a finalized report.

Impact of confinement in vehicle trunks on decomposition and entomological colonization of carcasses.

In order to investigate the impact of confinement in a car trunk on decomposition and insect colonization of carcasses, three freshly killed pig (Sus scrofa domesticus Erxleben) carcasses were placed individually in the trunks of older model cars and deployed in a forested area in the southwestern region of British Columbia, Canada, together with three freshly killed carcasses which were exposed in insect-accessible protective cages in the same forest. Decomposition rate and insect colonization of all carcasses were examined twice a week for four weeks. The exposed carcasses were colonized immediately by Calliphora latifrons Hough and Calliphora vomitoria (L.) followed by Lucilia illustris (Meigen), Phormia regina (Meigen) and Protophormia terraenovae (R.-D.) (Diptera: Calliphoridae). There was a delay of three to six days before the confined carcasses were colonized, first by P. regina, followed by Pr. terraenovae. These species represented the vast majority of blow fly species on the confined carcasses. Despite the delay in colonization, decomposition progressed much more rapidly in two of the confined carcasses in comparison with the exposed carcasses due to the greatly increased temperatures inside the vehicles, with the complete skeletonization of two of the confined carcasses ocurring between nine and 13 days after death. One confined carcass was an anomaly, attracting much fewer insects, supporting fewer larval calliphorids and decomposing much more slowly than other carcasses, despite similarly increased temperatures. It was later discovered that the vehicle in which this carcass was confined had a solid metal fire wall between the passenger area and the trunk, which served to reduce insect access and release of odors. These data may be extremely valuable when analyzing cadavers found inside vehicle trunks.

Effect of arson fires on survivability of entomological evidence on carcasses inside vehicle trunks.

Three vehicles with trunks containing pig (Sus scrofa domesticus Erxleben) carcasses which had been allowed to decompose for 30 days, were set alight in controlled burns to determine whether forensically valuable insect evidence could still be recovered. Each car trunk contained the remains of a carcass, together with its associated carrion insect fauna. An insect collection was performed prior to the fires. Each car was then set alight using a small amount of gasoline as an accelerant, poured onto the driver's seat, lit by a burning stick. The fire was allowed to reach its peak before being extinguished. In all cases, the fires completely destroyed the vehicles. The vehicles were examined the following day and insect evidence was collected. In all cases, large amounts of burned, charred and undamaged insect evidence remained, including identifiable prepuparial 3rd instar larvae, live pupae inside intact puparia and empty puparial cases. As well bones and unburned clothing were also intact. One car did not burn as well as the others with the fire not involving the trunk area as much as in the other cars. Once the fire was extinguished, it was clear that the reason for this was the presence of a steel fire wall, between the passenger compartment and the trunk. This reduced the spread of the fire to the trunk and increased evidence survival. However, in all vehicles, insect evidence survived, which could still be used to estimate the period of insect colonization and thereby infer the minimum elapsed time since death. The evidence was also a clear indicator that the decedent had not died in the fire. After the fire, the carcass remains were still attractive to blow fly adults (Diptera: Calliphoridae). In car fire cases it is important to consider that entomological evidence may still be just as useful in the investigation as in non-burned cases.

Hyperspectral measurements of immature Lucilia sericata (Meigen) (Diptera: Calliphoridae) raised on different food substrates.

Immature Lucilia sericata (Meigen) raised on beef liver, beef heart, pork liver and pork heart at a mean temperature of 20.6°C took a minimum of 20 days to complete development. Minimum development time differences within stages were observed between the meat types (pork/beef), but not the organ types (liver/heart). Daily hyperspectral measurements were conducted and a functional regression was completed to examine the main effects of meat and organ type on daily spectral measurements. The model examined post feeding larval spectral measurements of insects raised on beef liver alone, the effect of those raised on pork compared with those raised on beef, the effect of those raised on heart compared with those raised on liver and the interactional effect of those raised on pork heart compared with those raised on beef liver. The analyses indicated that the spectral measurements of post feeding L. sericata raised on pork and beef organs (liver and heart) are affected by the meat and organ type.

Initial investigations of spectral measurements to estimate the time within stages of Protophormia terraenovae (Robineau-Desvoidy) (Diptera: Calliphoridae).

Current applications of forensic entomology to post-mortem interval estimations involve ageing the insects colonizing the remains based on minimum time to reach the oldest stage of development. Immature species of blow fly develop at a predictable rate to each stage of development in their lifecycle. Unfortunately, the minimum time to reach a stage of development can be a rather unrefined estimate of tenure on the body in the sometimes lengthy time frame of the later stages. In a successful attempt to narrow this time frame, daily spectral measurements of the immature stages of Protophormia terraenovae (Robineau-Desvoidy) raised at a mean temperature of 24.6°C were collected and the functional data analysis was completed. Functional regressions and coefficient functions were examined for model prediction and generalization. P. terraenovae is a Holarctic species as well as an early colonizer of human remains and is therefore, an excellent indicator species in North American death investigations. Spectral measurements can be used successfully to estimate the day of development in the third instar including post feeding stage. In the intra-puparial period, however, only the last day of development could be distinguished from the earlier days of the intra-puparial period. Distinguishing day within second instar is also possible for P. terraenovae raised at a mean temperature of 24.6°C and, although not fully within the pointwise 95% confidence interval, it still accurately predicts the day. The results of this proof of concept research are promising and show a potential method for narrowing the original death estimates and offering a better overall estimate of age of P. terraenovae larvae and, therefore; estimated time since death.

Spectral Signatures of Immature Lucilia sericata (Meigen) (Diptera: Calliphoridae).

Hyperspectral remote sensing is an innovative technology with applications in many sciences and is a non-destructive method that may offer more precise aging within development stages. Hyperspectral reflectance measurements from the anterior, midsection, and posterior of Lucilia sericata (Meigen) larvae and pupae were conducted daily from samples of the developing insects beginning at second instar. Only midsection measurements were conducted on second instar larvae due to their size, to ensure that the measurement was not of reflective surroundings. Once measured, all insects were washed with deionized water, blotted with filter paper, and re-measured. Daily age prediction during the post-feeding stage was not impacted by the unwashed insect measurements and was best predicted based on posterior measurements. The second and third instar larvae, which move about their food source, had different contributing coefficients to the functional regression model for the hyperspectral measurements of the washed compared with unwashed specimens. Although washing did not affect the daily prediction within these stages, it is still encouraged in order to decrease the effect of food source on spectral reflectance. Days within the intra-puparial period were best predicted based on anterior measurements and were not well distinguished from one another in the first few days based on midsection and posterior measurements.

Comparison of Faunal Scavenging of Submerged Carrion in Two Seasons at a Depth of 170 m, in the Strait of Georgia, British Columbia.

The taphonomy of carcasses submerged in the ocean is little understood, yet it is extremely important ecologically and forensically. The objectives of this study were to determine the fate of pig carcasses as human proxies in the Strait of Georgia at 170 m in spring and fall. Using Ocean Networks Canada's Victoria Experimental Network Underseas (VENUS) observatory, two carcasses per season were placed under a cabled platform hosting a webcam and instruments measuring water chemistry. Two minutes of video were recorded every 15 min. In spring, Lyssianassidae amphipods and Pandalus platyceros were immediately attracted and fed on the carcasses, the amphipods removed the bulk of the soft tissue from the inside whilst the shrimp shredded the skin and tissue. The carcasses were skeletonized on Days 8 and 10. In fall, Metacarcinus magister was the major scavenger, removing most of the soft tissue from one carcass. Amphipods did not arrive in large numbers until Day 15, when they skeletonized the scavenged carcass by Day 22 and the less scavenged carcass by Day 24. Amphipods remained for some days after skeletonization. This skeletonization was very different from previous experiments at different depths and habitats. Such data are very valuable for predicting preservation, planning recoveries, and managing family expectations.

A Preliminary Study of Insect Succession in Al-Ahsaa Oasis, in the Eastern Region of the Kingdom of Saudi Arabia.

Rabbit carcass decomposition was examined in four seasons in Al-Ahsaa Oasis. Decomposition rate was significantly faster in summer compared with other seasons. Fourteen insect species from four orders and seven families were recorded: Calliphoridae, Muscidae, Sarcophagidae, Formicidae, Histeridae, Dermestidae, and Tenebrionidae. Most of the fly maggots collected were Calliphoridae with only one species from both Muscidae and Sarcophagidae. Maggots of Calliphora vicina (R.-D.) and Chrysomya albiceps (Wiedemann) colonized the carcasses in all seasons while both Ch. bezziana (Villeneuve) and Lucilia sericata (Meigen) were found in all seasons except for winter. Maggots of Chrysomya megacephala (F.) and Phormia regina (Meigen) were only collected in the summer and autumn, respectively. Four coleopteran species were collected: Hymenorus sp., Saprinus chacites (Illiger), Dermestes maculatus DeGeer and Blaps sp. One formicidian species, Pheidole megacephala (F.), was observed in all seasons. Insect richness was greater, and decomposition rate was faster in summer compared with other seasons.

Impact of Marine Submergence and Season on Faunal Colonization and Decomposition of Pig Carcasses in the Salish Sea.

Pig carcasses, as human proxies, were placed on the seabed at a depth of 300 m, in the Strait of Georgia and observed continuously by a remotely operated camera and instruments. Two carcasses were deployed in spring and two in fall utilizing Ocean Network Canada's Victoria Experimental Network under the Sea (formerly VENUS) observatory. A trial experiment showed that bluntnose sixgill sharks could rapidly devour a carcass so a platform was designed which held two matched carcasses, one fully exposed, the other covered in a barred cage to protect it from sharks, while still allowing invertebrates and smaller vertebrates access. The carcasses were deployed under a frame which supported a video camera, and instruments which recorded oxygen, temperature, salinity, density, pressure, conductivity, sound speed and turbidity at per minute intervals. The spring exposed carcass was briefly fed upon by sharks, but they were inefficient feeders and lost interest after a few bites. Immediately after deployment, all carcasses, in both spring and fall, were very rapidly covered in vast numbers of lyssianassid amphipods. These skeletonized the carcasses by Day 3 in fall and Day 4 in spring. A dramatic, very localized drop in dissolved oxygen levels occurred in fall, exactly coinciding with the presence of the amphipods. Oxygen levels returned to normal once the amphipods dispersed. Either the physical presence of the amphipods or the sudden draw down of oxygen during their tenure, excluded other fauna. The amphipods fed from the inside out, removing the skin last. After the amphipods had receded, other fauna colonized such as spot shrimp and a few Dungeness crabs but by this time, all soft tissue had been removed. The amphipod activity caused major bioturbation in the local area and possible oxygen depletion. The spring deployment carcasses became covered in silt and a black film formed on them and on the silt above them whereas the fall bones remained uncovered and hence continued to be attractive to large numbers of spot shrimp. The carcass remains were recovered after 166 and 134 days respectively for further study.

Deep coastal marine taphonomy: investigation into carcass decomposition in the Saanich Inlet, British Columbia using a baited camera.

Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada's VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans' feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustacea endured stressful levels of oxygen to access the carcasses for much of the time. These data will be valuable in forensic investigations involving submerged bodies, indicating types of water conditions to which the body has been exposed, identifying post-mortem artifacts and providing realistic expectations for recovery divers and families of the deceased.

Effect of fluctuating temperatures on the development of a forensically important blow fly, Protophormia terraenovae (Diptera: Calliphoridae).

Experiments were conducted to compare the immature development of Protophormia terraenovae (Robineau-Desvoidy) at fluctuating temperatures of 4-28 and 9-23 °C to their mean constant temperature, 16 °C. Overall development was fastest at the greater fluctuation and slowest at the constant temperature but showed similar percentages of development time in each stage. The rate summation effect is suspected to have caused this difference in development rate because fluctuations above the mean increase the rate relatively more than temperatures below the mean can lower the rate.

Comparison of decomposition rates and faunal colonization of carrion in indoor and outdoor environments.

Decomposition and insect colonization of pig (Sus scrofa L.) carcasses were observed over a 42-day period inside and outside a house in a suburban region of Edmonton, Alberta. Three freshly killed pig carcasses were placed outdoors on grass and three carcasses were placed in separate rooms inside a house in a suburban residential area. The carcasses were examined and sampled regularly. Outside carcasses were colonized rapidly by Calliphora vicina (R-D), Lucilia sericata (Meigen), Lucilia illustris (Meigen), Eucalliphora latifrons (Hough), Cynomya cadaverina (R-D), Phormia regina (Meigen), and Protophormia terraenovae (R-D). There was a delay of 5 days before inside carcasses were first colonized but all species except E. latifrons and L. illustris readily colonized at this time. Many more insects colonized the outside carcasses, and these were rapidly skeletonized. Inside, much fewer insects were present and decomposition was slowed and colonization extended. Dispersal patterns of postfeeding larvae inside the house on hard substrate were greatly expanded compared with those from carcasses on grass.

Arthropods of forensic importance on pig carrion in the Coahuilan semidesert, Mexico.

This is the first report of an ongoing research to establish a sarcosaprophagous arthropod database in the Coahuilan semidesert. Seven pigs (Sus scrofa L.) were used as human models to determine succession in an open urban area during the 2007 winter-spring period. Arthropods were collected manually and from pitfall traps. Carcass biomass loss, as well as arthropod colonization, was recorded during 71 days postmortem. Five decomposition stages were identified during which most abundant orders were found to be Diptera, Coleoptera, and Hymenoptera. Lucilia sericata (Meigen), Chrysomya rufifacies (Macquart), Necrobia rufipes (DeGeer), Dermestes maculatus (DeGeer), Pheidole hyatti Emery, and Pogonomyrmex rugosus Emery stood out as dominant species.

The influence of clothing and wrapping on carcass decomposition and arthropod succession during the warmer seasons in central South Africa*.

The influence of clothing and wrapping on carcass decomposition and arthropod succession was investigated to provide data to enable estimated postmortem interval in homicide investigations. Six pig carcasses, Sus scrofa, were divided into three sample groups, each with a clothed carcass wrapped and a carcass wrapped with no clothes. Two more carcasses, one with no clothes or wrapping, the other with clothes and no wrapping were used as controls. The clothed or wrapped carcasses had larger visible maggot masses, which moved more freely and these carcasses took longer to dry out. The blow fly maggot masses were dominated by Chrysomya marginalis and Chrysomya albiceps. Oviposition occurred simultaneously on all carcasses. High temperatures in one case caused significant maggot mortality. The Coleoptera community was dominated by Silphidae, Thanathopilus micans larvae, Dermestidae, Dermestes maculatus adults and larvae, and Cleridae, Necrobia rufipes.

Insect succession and decomposition patterns on shaded and sunlit carrion in Saskatchewan in three different seasons.

A study was conducted on decomposition and insect succession in the Prairie Ecozone of Saskatchewan in the year 2000. Eighteen domestic pig carcasses (42-79 kg) were employed as human models for applications to future homicide investigations in this region. Two major variables were considered including the effect of season and habitat (sun versus shade). Research was conducted over 25 weeks, spanning three seasons: spring, summer and fall. Ambient temperature, internal carcass temperature, faunistic succession over time, and the rate of decay were all compared for each experimental variable. Results indicated that habitat was only a factor in the decompositional rate of carrion in the spring season. The ambient temperature was the chief factor determining the seasonal variations in decay rate. Maximum internal carcass temperatures always coincided with the presence of 3rd instar larvae. Patterns of insect succession occurred in a predictable sequence that varied across different habitats and seasons and was unique compared to previously published studies. Carcasses placed in spring and fall attracted a more diverse assemblage of insects than summer-placed carrion. Sun-exposed carrion also had greater variation in fauna than shaded carrion in spring and fall. Members of Silphidae were the first coleopteran colonizers in all habitats and seasons. This paper also marks the first record for Cochliomyia macellaria (Fabricius) in Saskatchewan.

Time of submergence using aquatic invertebrate succession and decompositional changes.

Pig carcasses were placed in pond and stream habitats in the Malcolm Knapp Research Forest in Maple Ridge, B.C. for approximately one year, to examine the development, species, and sequence of invertebrates associated with the carrion. An invertebrate successional database was created for pond and stream habitats for potential use in estimating time of submergence in water related death investigations. Analysis has shown that a predictable succession of invertebrates colonize the carrion. However, whether or not this succession is carrion dependent or seasonal is unknown. There is a difference in the species composition between pond and stream habitats. Habitats influence invertebrate fauna, therefore, species colonizing carrion are habitat-specific. In both habitats, no one organism can determine time of submergence alone. Decompositional descriptions from this research were compared with 15 freshwater related death investigations. Similarities were seen in the earlier decompositional characteristics including bloat, discoloration, and nail shedding; however, the human descriptions were so vague that they had little value in determining time of submergence and hence time of death.