Centre for Sustainable Ecosystem Solutions, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales, Australia.
School of Science, Psychology, and Sport, Federation University Australia, Mount Helen, Victoria, Australia.
J Forensic Sci. 2021 Nov;66(6):2319-2328. doi: 10.1111/1556-4029.14870. Epub 2021 Sep 22.
Fly development rates, and to a lesser extent succession data, can be used to provide an estimate of a minimum postmortem interval (mPMI). Yet, these data are most useful when a full account of species' ecology, seasonality, and distribution is known. We conducted succession experiments on human cadavers over different seasons near Sydney, Australia, to document forensically useful information, including the pre-appearance interval for carrion flies. We also compiled a detailed record of flies identified in casework collected in 156 cases distributed across New South Wales, Australia. We then compared the occurrence of fly species from both field and casework datasets to identify any consistencies or gaps to determine how useful species might be for forensic investigations. In the field experiments, we found differences in species diversity and abundance between seasons, as well as yearly variation between two winter seasons. Most fly species we recorded ovipositing showed a 2- or 3-day delay between adult arrival and oviposition in summer, with a longer delay in winter. Species that were previously encountered in casework, such as Calliphora augur (Fabricius, 1775) and Calliphora ochracea Schiner, 1868, were confirmed as forensically useful, with their colonization behavior and seasonal preferences documented here. Although not encountered in casework, we confirmed Hemipyrellia fergusoni Patton, 1925 as a primary colonizer of human cadavers. Our study emphasizes the need to link field and casework data for a complete understanding of all aspects of a carrion fly's ecology to assist forensic investigators in mPMI estimations.
蝇类的发育速率，在一定程度上还有演替数据，可用于估计最低死后间隔时间（mPMI）。然而，只有在充分了解物种的生态、季节性和分布情况时，这些数据才最有用。我们在澳大利亚悉尼附近的不同季节对人体尸体进行了演替实验，以记录法医学上有用的信息，包括腐肉蝇出现前的间隔时间。我们还详细记录了在澳大利亚新南威尔士州收集的 156 个案例中发现的蝇类。然后，我们将实地和案例数据集中蝇类的出现情况进行了比较，以确定是否存在一致性或差距，从而确定哪些物种可能对法医调查有用。在野外实验中，我们发现季节之间物种多样性和丰度存在差异，以及两个冬季之间的年度变化。我们记录到的大多数产卵蝇种在夏季成虫到达和产卵之间存在 2 到 3 天的延迟，冬季延迟时间更长。在案例工作中遇到的一些蝇种，如巨尾阿丽蝇（Calliphora augur（Fabricius，1775））和黄尾丽蝇（Calliphora ochracea Schiner，1868），其繁殖行为和季节性偏好已被证实具有法医学价值。虽然在案例工作中没有遇到，但我们确认了黑边腐蝇（Hemipyrellia fergusoni Patton，1925）是人体尸体的主要殖民者。我们的研究强调了需要将实地和案例数据联系起来，以全面了解腐肉蝇生态学的各个方面，从而协助法医调查人员进行 mPMI 估计。
