Forensic Entomology and its Impacts in Forensic Science
Jordan Green 25 April, 2014 Entomology I Love
Entomology Forensic Entomology • Branch of Zoology that studies entomological significance in criminal cases involving animal abuse, neglect, and homicide
• One of the youngest and least represented branches of forensic science
• Deals most heavily with: flies (Calliphoridae, Sarcophagidae, Muscidae), and beetles (Histeridae, Dermestidae, Staphylinidae) Uses for Forensic Entomology
Medicocriminal: Civil Proceedings Abuse and neglect cases Homicide Investigations
Photos courtesy Dr. Heather Ketchum, University of Oklahoma Blow Fly Life Cycle Stages of Decay
• Fresh ------
• Bloat
• Active
• Dry Fresh Staphylinidae
Calliphoridae Silphidae Bloat Staphylinidae Calliphoridae
Silphidae Cleridae
Histeridae Sarcophagidae Active Staphylinidae
Calliphoridae
Silphidae Cleridae
Sarcophagidae Histeridae Scarabaeidae Dermestidae Dry Silphidae Calliphoridae
Scarabaeidae
Nitidulidae
Trogidae
Cleridae Histeridae But What does it Mean? The process just described is called Succession
Insect 1
Insect 2 Insect 3
Insect 2 Insect 4 Insect 3
Insect 4 Post-Mortem Interval Succession, stage of decay, and maggot development are used in the calculation of PMI
Assumption: Flies detect and oviposit on corpse soon after death Question:
Can post mortem interval be accurately determined using succession in homicides set in dissimilar ecological surroundings? Arthropod Activity Results
• While differing habitats produced minor changes in arthropod diversity, a noticeable difference was still perceived • Differences in fly development, when coupled with temperature and relative moisture content of habitats provided accurate PMI determinations • As few as two species of fly can significantly alter PMI calculations Future Considerations • Succession studies in other environments
• Changes in succession due to carcass tampering (burying, hanging, burning)
• Affects of repeated desiccation and rehydration of carcasses Acknowledgements
• Nadine McCrady-Borovicka, M.S. • Dr. Pamela Staton • Dr. Nathan Green References
• Amendt, J., C. S. Richards, C. P. Campobasso, R. Zehner, and M. J. R. Hall. 2011. Forensic entomology: applications and limitations. Forensic Sci. Med. Pathol. 7: 379-392. • Campobasso, C. P., G. Di Vella, and F. Introna. 2001. Factors affecting decomposition and Diptera colonization. Forensic Sci. Int. 120: 18-27. • Goff, M. L. 2000. A Fly for the Prosecution: How Insect Evidence Helps Solve Crimes, Harvard University Press, Cambridge, MA. • Goff, M. L., A. I. Omori, and K. Gunatilake. 1988. Estimation of postmortem interval by Arthropod succession. Am. J. Forensic Med. Pathol. 9: 220-225.
References Cont. • Matuszewski, S., D. Bajerlein, S. Konwerski, and K. Szpila. 2010. Insect succession and carrion decomposition in selected forests of central Europe, part 1: pattern and rate of decomposition. Forensic Sc. Int. 194: 85-93. • Matuszewski, S., D. Bajerlein, S. Konwerski, and K. Szpila. 2011. Insect succession and carrion decomposition in selected forests of central Europe. part 3: succession of carrion fauna. Forensic Sc. Int. 207: 150-163. • McNeil, J. 2012. The ecology of death: forensic entomology as a teaching tool. Am. Biol. Teach. 72: 153- 155. • Insecta. Wikipedia. http://en.wikipedia.org/wiki/Insect. 2014. 08 April 2014. Picture References • Dermestidae. http://www.insectoid.info/pictures/dermestidae.jpg • Cleridae. http://www.zin.ru/animalia/coleoptera/images/h_800/ne crobia_rufipes.jpg • Histeridae. http://www.kerbtier.de/Pages/Fotos/Familien/Histeridae .jpg • Life Cycle. http://www.monarchlabs.com/images/maggotLifeCycle Small.gif • Lucilia Cuprina. http://bugguide.net/images/cache/6Z0L5ZQLNZ5HFH 7HFHEHLR9HZRGLZR8H5Z5HCHQLCH7HBHHL
Picture References Cont.
• Nitidulidae. http://www.entomology.wisc.edu/irc/wibeetles/New%2 0Images/nitbi_medbutton.jpg • Sarcophagidae. http://www.fnanaturesearch.org/images/stories/ns/mark ed/M/4232.jpg • Scarabidae. http://collectionneurdinsectes.com/wp- content/uploads/2013/05/p-batesi1.jpg • Silphidae. http://www.saltuna- bornholm.dk/humator_demo.jpg • Staphylinidae. http://www.zin.ru/animalia/coleoptera/images/foto/GDI 128.jpg • Trogidae. http://farm7 staticflickr com/6077/6085527917 d2d977
Questions?