Fly artefacts or bloodstains?

Congratulations to CHEW Weh, a Chemistry and Forensic Science fresh graduate and Assoc Prof Stella TAN on receiving the CRISP award for their research on the effect of fly artefacts on bloodstain pattern analysis. 

A course on forensic entomology piqued Chew Weh’s interest, and he decided to investigate how necrophagous fly artefacts – stains left behind at crime scenes by flesh-eating flies that resemble blood stains – can impact efforts to accurately reconstruct a crime scene. To address this issue, he developed methods to characterise and differentiate these artefacts from genuine bloodstains.

As part of his Undergraduate Research Opportunities Programme in Science (UROPS) project, he characterised fly artefacts based on their morphology, including shape, colour, and size. He then used an Alternate Light Source (ALS) that emitted light at a specific wavelength to differentiate artefacts from bloodstains. This methodology has the potential to simplify the reconstruction of bloodied crime scenes complicated by the presence of fly artefacts.

Working with flies posed some challenges. Chew Weh had to provide plastic containers with water and sugar to rear the flies, c-fold paper towels for adult flies to rest on, and rearing cups filled with pet sawdust and protein to support the growth of fly larvae. Heavy rain also delayed his research as it hindered his ability to set up fly traps.

However, the experience was worth his while.  He says, “UROPS is a once-in-a-lifetime experience that enabled me to develop laboratory skills and design my own experiments.” 

Prof Tan says, “Knowing that I played a pivotal role in shaping my students’ professional journeys motivates me to continue mentoring them.” She guides them in their research, bringing them through the processes and methodologies which are crucial for conducting rigorous, data-driven and scientifically sound research, writing reports and making presentations.

She adds, “It is very gratifying to witness the growth and accomplishments of my mentees!” 

Find out more about UROPS here!