Forensic entomology is the scientific study of insects and their role in criminal investigations. It mainly involves analysing the life cycles of insects that colonise decomposing bodies, assisting investigators in estimating the post-mortem interval (PMI), which is the time elapsed since death. This discipline combines biology, ecology, and law, making it a valuable tool for modern forensic science.
The use of insects in criminal cases is not new. Historical records from Asia and Europe describe how insect evidence was once used to reveal murder cases centuries ago. However, the field became more structured in the 20th century, particularly after World War II, when entomology began playing a routine role in criminal investigations. Today, forensic entomology is recognised as an essential Branch of forensic science with established guidelines and best practices.
The principles are straightforward: insects colonise a body in a predictable order. Blowflies (Family-Calliphoridae) are usually the first to arrive, often within minutes of death, depositing eggs in natural body openings and wounds. These eggs hatch into larvae, which pass through different developmental stages that can be measured to calculate PMI. Later, Beetles and other insects arrive, feeding on tougher tissues. This sequence, known as faunal succession, provides critical evidence about the timeline of death.
Applications go beyond homicide. Insects have helped prove cases of neglect in children and the elderly, revealed drug or poison traces in tissues, and even confirmed whether a body was moved after death. Despite its power, the field faces challenges, including environmental factors that impact insect growth and the need for region-specific insect data.
In conclusion, Forensic entomology demonstrates how even the smallest creatures can reveal the most significant truths. By studying insects, forensic experts give victims a voice and help the justice system uncover the hidden story behind death.