Effects of different environmental factors on...

Effects of different environmental factors on Sarcophaga haemorrhoidalis life cycle and its related impact on the accuracy in determining the post-mortem interval

Author Name : Narjis Zehra, Vichar Mishra

ABSTRACT: Forensic Entomology is the study of the arthropods that inhabit decomposing remains, to aid legal investigations.When we try to explain why an insect is present in a particular forensic setting, it is very important to “think like an insect” and to try to understand their lives and motivations. The purpose of this study was to determine the impact of various environmental factors on the growth and development of flesh flies and their related effect on the accuracy in determining the post-mortem interval. The most reliable biological indicator and sometimes the only method of determining elapsed time since death in decomposition cases is flesh fly development. Since insects cannot maintain a constant body temperature; development is a function of time and temperature. In the present study the life cycle stages of Sarcophaga haemorrhoidalis was recorded. The duration of life cycle stages changed as per the temperature and humidity variations in open and closed environments. It was observed that at low range of temperature (27 – 30.3oC) and humidity (29-38%) in closed environment, the adult emerged out from the pupae earlier by 2 days than at high range of temperature(18.3 – 41oC) and humidity (20-66%) range in the open. This study shows that forensic entomologists will have to take into account each of these variables that effect the development of insects in order to provide an accurate estimation of the postmortem interval (PMI).