Variability in Blow-Fly Development - Research & Implications for PMI Practice - Archival
Dr. Leon Higley’s work to characterize blow-fly species indicates that there is variation within a single population--the bell curve is wide. Dr. Higley will share his research and discuss how the science is challenging some notions about PMI analysis.
Dr. Higley is focused on science that adds rigor and quality to the courtroom testimony of PMI experts. He will discuss his research in the context of how science is challenging notions. Ultimately, his research may impact the establishment of science-based maxima and minima in establishing PMI estimates in forensics. Some specific research topics that will be covered in the webinar include: Blow-fly variability in a single population: new research shows that there is more variability in fly development than previously thought, even within a single population. Dr. Higley has completed the characterization of one species, Lucilia sericata. The data showed more variability in fly development than was previously thought. In effect the distribution curve was flatter. The impact is that the research indicates that the Time of Death, statistically, should be provided as a range. His research continues with the characterization of a second species, Phormia Regina. Blow-fly wandering behavior: The previous assumption was that blow-flies wandered until they found safety or shelter or reached a development stage. Dr. Higley’s research challenges this notion as science indicates that the wandering that happens between the second and third pupae stage is strongly correlated to temporal period. Blow-fly variability by geography: The previous assumption was that blow-fly development varies by geography. Higley challenges this notion claiming they do not vary by geography. Detailed Learning Objectives: 1. New research shows that there is more variability in fly development than previously thought, even within a single population. 2. The implication of the research is that time of death statistically should be presented as a range, and that there may be a misuse of minima and maxima in courtroom expert estimates of PMI based on blow-fly development 3. Ultimately, this research impacts the how the forensic community builds standards and procedures for using blow-fly development to measure PMI. This webinar was recorded in its entirety at the time of the Live event in order to capture the one on one interaction with the presenter. Funding for this Forensic Technology Center of Excellence event has been provided by the National Institute of Justice.