Extensive unusual lesions on a large number of immersed human victims found to be from cookiecutter sharks (Isistius spp.): an examination of the Yemenia plane crash

Abstract

Accurate determination of the origin and timing of trauma is key in medicolegal investigations when the cause and manner of death are unknown. However, distinction between criminal and accidental perimortem trauma and postmortem modifications can be challenging when facing unidentified trauma. Postmortem examination of the immersed victims of the Yemenia airplane crash (Comoros, 2009) demonstrated the challenges in diagnosing extensive unusual circular lesions found on the corpses. The objective of this study was to identify the origin and timing of occurrence (peri- or postmortem) of the lesions.A retrospective multidisciplinary study using autopsy reports (n = 113) and postmortem digital photos (n = 3 579) was conducted. Of the 113 victims recovered from the crash, 62 (54.9 %) presented unusual lesions (n = 560) with a median number of 7 (IQR 3 ∼ 13) and a maximum of 27 per corpse. The majority of lesions were elliptic (58 %) and had an area smaller than 10 cm2 (82.1 %). Some lesions (6.8 %) also showed clear tooth notches on their edges. These findings identified most of the lesions as consistent with postmortem bite marks from cookiecutter sharks (Isistius spp.). It suggests that cookiecutter sharks were important agents in the degradation of the corpses and thus introduced potential cognitive bias in the research of the cause and manner of death. A novel set of evidence-based identification criteria for cookiecutter bite marks on human bodies is developed to facilitate more accurate medicolegal diagnosis of cookiecutter bites.

Crime scene and body alterations caused by arthropods: implications in death investigation

“…Cadavers collected from water often show post-mortem lesions caused by water turbulence, contact with the bottom of the river but as well as by the feeding activity of fluvial and marine scavengers, the latter including cookiecutter sharks, small size fish, deep sea crabs and mollusks [62][63][64].…”

Barnacle colonization of shoes: Evaluation of a novel approach to estimate the time spent in water of human remains

“…Generally, the soft tissues of a decomposed corpse are rarely colonized due to their slimy texture or the formation of adipocere that does not facilitate the settlement of organisms (6,16,17). Furthermore, such tissues are often scavenged by aquatic sea-life (mostly crustaceans, fish and sharks) and sea-birds (7,10,36). Despite research in the area of underwater microbiomes, little is understood about how microbial communities interact with carcasses located underwater (37).…”

“…Despite research in the area of underwater microbiomes, little is understood about how microbial communities interact with carcasses located underwater (37). However, case studies of bodies found in the marine environment reported in the literature indicate barnacles are able to colonize bones and teeth (1,27,29), as well as clothing and shoes associated with a decomposing body (6,7,19). When the environmental conditions are suitablewater temperature is between the lower and higher developmental threshold of the species and an appropriate substrate is The aim of the present research was for the first time to consider the barnacle colonization of two types of shoes placed in the sea, providing another tool for forensic investigations.…”

“…In instances of homicide, bodies may be left in the water after drowning or may be dumped into the water in order to cover up a crime. Mass disasters determined by natural causes, such as flooding or tsunamis, often result in large numbers of bodies becoming displaced as well as being relocated over large distances (7,8).…”

Cranial morphology in Mollisquama sp. (Squaliformes; Dalatiidae) and patterns of cranial evolution in dalatiid sharks

“…; Ribéreau‐Gayon et al. ). In Isistius, feeding is accomplished via scooping of the jaw and twisting of the body to extract a tissue plug from prey, and ingestion of the plug via strong negative pressure generation in the buccal cavity (Shirai & Nakaya, ).…”