Activity for Solving Crimes with the Necrobiome
This activity explores content presented in the animated video Solving Crimes with the Necrobiome, which describes the microbial changes associated with decomposing corpses.
In the video, Ed Yong and scientist Jessica Metcalf describe how a community of many microbes, known as the necrobiome, takes over our bodies after we die. Scientists study the necrobiome to better understand the process of decomposition. This research also provides tools for criminal investigators. For example, forensic experiments have shown that it may be possible to estimate time of death by sequencing the DNA of microbes found on and around corpses.
The “Student Handout” probes students’ understanding of the key concepts addressed in the film. The “Educator Materials” document provides suggested pause points in the film with questions for students, background information, and detailed discussion points; a list of related resources and references; and an answer key for the “Student Handout.”
Student Learning Targets
- Describe the process of decomposition and the role it plays in an ecosystem.
- Explain how the microbiome associated with a decomposing body can be used to estimate the time since death.
- Interpret evidence to support or refute a scientific argument.
crime scene investigation, decomposition, DNA sequencing, ecological succession, forensics, microbiome, nutrient cycling, time of death
Metcalf, Jessica L., Laura Wegener Parfrey, Antonio Gonzalez, Christian L. Lauber, Dan Knights, Gail Ackermann, Gregory C. Humphrey, et al. "A microbial clock provides an accurate estimate of the postmortem interval in a mouse model system." eLife 2 (2013). https://doi.org/10.7554/elife.01104.
Metcalf, Jessica L., Zhenjiang Zech Xu, Sophie Weiss, Simon Lax, Will Van Treuren, Embriette R. Hyde, Se Jin Song, et al. “Microbial community assembly and metabolic function during mammalian corpse decomposition.” Science 351, 6269 (2016): 158–162. https://doi.org/10.1126/science.aad2646.
Pechal, Jennifer L., Tawni L. Crippen, M. Eric Benbow, Aaron M. Tarone, Scot Dowd, and Jeffery K. Tomberlin. “The potential use of bacterial community succession in forensics as described by high throughput metagenomic sequencing.” International Journal of Legal Medicine 128, 1 (2014): 193–205. https://doi.org/10.1007/s00414-013-0872-1.
2.A.2, 2.A.3, 4.A.5, 4.A.6
II.A, II.B, II.C, II.E
4.1, 4.2, C.2