Forensic Entomology

 Forensic entomology or legal practitioner, is the study of arthropods associated with corpses, is used, among other purposes, to estimate the time elapsed since death or postmortem interval (IPM) and the identification of possible body transfers, as well as the characteristics of the areas of origin.

    The postmortem entomological episodes, in summary, begin with the diptera, then coleoptera usually appear and for a time they will live in different niches, beetles and diptera, and finally, they will also live in different niches, beetles, mites and lepidoptera. But the colonization sequence itself and the species involved will vary according to multiple parameters, among which the biogeographical region, the time of year and the particular environmental characteristics of the habitat in which the corpse is found stand out.

The time elapsed since death is a matter of crucial importance from the legal point of view, to establish guilt or to identify the missing person. One of the methods to determine it is the external observation of the corpse, which includes factors such as body temperature, cadaverous lightness, rigidity, signs of dehydration, external injuries, action by animals and invasion of insects. In human bodies it is estimated by various methods: histological, chemical, and zoo. However, after 72 hours, forensic entomology is usually the best method and in many cases the only method to establish the postmortem interval.


    There are two methods to determine the time elapsed since death using arthropod evidence, the first uses age and larval development rate; the second method uses the succession of arthropods in the decomposition of the body. Both methods can be used separately or together, always depending on the type of remains being studied. In the early stages of decomposition, estimates are generally based on the study of the growth of one or two species of insects, particularly diptera, while in the more advanced stages the composition and degree of growth of the community of arthropods found in the body and compared with known patterns of fauna succession for the closest habitat and conditions.History of forensic entomology


    The presence of flies is documented in early writings such as “Table 14”, from the Harra-Hubulla series (systematic list of terrestrial wild animals from the Hammurabi era), about 3,600 years ago. In it the “green fly” (Lucilia) and the “blue fly” (Calliphora) are mentioned for the first time, common in forensic cases. In ancient civilizations, flies and beetles appear as amulets, on cylinder seals, as a god, and as one of the plagues of the Biblical history of Exodus, but it was Aristotle who provided anatomical and biological data that he described and classified within the scientific order .

    The birth of criminal medical entomology occurred in the 13th century, in China, when in 1235 BC, Sung Tz'u wrote a book "The Washing Away of Wrongs", here is the first written document of a case solved by forensic entomology.

    It was not until the middle of the 19th century, in France, that science emerged as such. Orfila (1848), listed 30 insects and other arthropods that colonized a body, his observations may be the first to systematize the knowledge of the succession of arthropods; although Bergeret (1855) is given credit for applying this knowledge to a criminal case, by evaluating the insect fauna, the IPM determined.

    J.P. Mégnin expanded and systematized the studies publishing "The fauna of the tombs" in 1887 and "the fauna of the corpses" in 1894, he identified eight stages of human decomposition; The described decomposition states were followed by Leclercq (1969), Easton and Smith (1970). The ecology and general behavior of flies of forensic importance were discussed extensively by Greenberg (1973) and Putman (1983); Fauna succession was studied in various regions in non-human carcasses, from lizards to pigs, providing information on the structure of the community, order of colonization, seasonality, and oviposition preferences of carrion flies.

    Criminal medical entomology entered a phase of rapid growth and development from the reviews by Leclercq (1978), Nourteva (1977), and became an exact discipline referring to forensic theory and practice. The forerunners have been able to integrate entomology and forensic science, and criminologists have rescued many details to obtain useful conclusions and a holistic vision of the subject.