Forensics for the Body Farm: Preferences for the Medicinal Blow Fly (Phaenicia sericata) and Fruit Fly (Drosophila melanogaster)

 

Oscar Istas, Abigail Greenhalgh, Erin E. Richard, Jate Bernard, Rebecca Krall, Tawny Aguayo, and Robin L. Cooper

Advances in Biology Laboratory Education, 2022, Volume 42

https://doi.org/10.37590/able.v42.art61

Supplemental Materials: https://doi.org/10.37590/able.v42.sup61

Poster file: https://doi.org/10.37590/able.v42.poster61

Abstract

Learning about bacteria, fungi, or the developmental stages of insects does not always have the “wow” factor for many college students. If you add a dead body to the mix, it’s amazing how their interest is piqued. An interactive forensic science module was developed with this storyline to provide an authentic forensic investigation of a dead animal. Forensic science considers many variables when documenting and determining conditions to identify the potential time frame of death. In particular, the presence, amount, and developmental stages of bacteria, fungi and insects are commonly used to aid investigations. The developmental stages and preference in behaviors of insects, and the decay of associated plant matter has proven to be particularly beneficial in determining the potential time frame of death of an animal. The case in this module presents a human that has died after taking a bite of fruit. Fruit flies and blow flies are found at the scene. Through experimentation, data gathering, and analysis of the life cycles and behavior of two animal models (fruit fly and blow fly), interpretations of the location of the insects and developmental stages of larvae and pupa lead to a logical assessment of the time of death. We simulated the experimental design of data collection at the scene using laminated copies of fruit fly and blow fly larvae in different developmental stages. The data set and specific details surrounding data collection are provided to support participants in determining the time frame of the animal?s death using an experimental protocol. Protocols are also provided to guide the re-creation of the scene using physical models. This lab was designed to be conducted in both the laboratory or remotely using downloadable materials. The laboratory could also be adapted as a CURE class project.

Keywords:  insects, Inquiry-based learning, field work, crime scene investigations

Virtual ABLE (ViABLE) (2021)