Theses and Dissertations

Forensic entomology is an important field of forensic science that utilizes insect evidence in criminal investigations. Blow flies (Diptera: Calliphoridae) are among the first colonizers of remains and are therefore frequently used in determining the minimum postmortem interval (mPMI). Blow fly development, however, is influenced by a variety of factors including temperature and feeding substrate type. Unfortunately, dietary fat content remains an understudied factor on the development process, which is problematic given the relatively high rates of obesity in the United States. To study the effects of fat content on blow fly development we investigated the survivorship, adult weight and development of Lucilia sericata (Meigen; Diptera: Calliphoridae) and Phormia regina (Meigen; Diptera: Calliphoridae) on ground beef with a 10%, 20%, or 27% fat content. As fat content increased, survivorship decreased across both species with P. regina being significantly impacted. While P. regina adults were generally larger than L. sericata across all fat levels, only L. sericata demonstrated a significant (P < 0.05) difference in weight by sex. Average total development times for P. regina are comparable to averages published in other literature. Average total development times for L. sericata, however, were nearly 50 hours higher. These findings provide insight on the effect of fat content on blow fly development, a factor that should be considered when estimating a mPMI. By understanding how fat levels affect the survivorship and development of the species studied here, we can begin improving the practice of insect evidence analysis in casework.

As Arizona State University moves toward virtual classroom accessibility and the fortification of education for all students around the globe (ASU Online), we must continue to develop and cultivate creative resources to bring STEM laboratory activities to those who do not have access to the resources found in many classrooms. Online science degree programs face a particular challenge, as laboratory activities must be reformatted and rethought for virtual application. ASU has recently launched an online Forensic Science major, and the ability to identify and analyze evidence at a crime scene is one of the most important skills a student-investigator can learn. The development of creative ways to address instruction in a virtual crime scene is essential to the success of this and similar programs. Through the process of identifying evidence, students can hone their critical thinking skills, as they are required to assess scenarios and decide which evidence is pertinent to a given case. By making decisions regarding the packaging of identified evidence, students learn important steps in any forensic job, such as chain of custody, the effects of material packaging on evidence preservation, and the ramifications of incorrect evidence handling. Currently, there are several virtual crime scene programs available for purchase (Crime Scenes Meet Virtual Reality | St. Edward’s University in Austin, Texas). These programs offer activities such as those described above, yet they present a financial hurdle and are not customizable for specific courses or environments. Through the use of Google Slides, this project yielded an accessible and easily replicable interactive learning experience. The project resulted in a virtual crime scene that was both intuitive and integrative of generally novice technological resources such as Google Enterprise. Clickable photo slides were constructed using the linked shape imagery tools on Google Slides in order to provide an immersive learning experience.