Crime Solving Insects

Transition through slides 16-17. Review what a forensic entomologist does. Students should continue to fill in their Forensic Entomologist Guided Notes handout.

Move to slide 18 and introduce the I Notice I Wonder strategy. Explain to students that they should go to the chart on their handout and add their reflections while watching the following video clip. Transition to slide 19 and play the Forensic Entomology video clip. 

Display slide 21 and explain how forensic entomologists use insects as evidence. If you are starting on a new day, remind students to get out their Guided Notes handout and continue filling it in. Move to slide 22 and invite students to draw visuals of how they understand the stages of body decomposition using the Cognitive Comics instructional strategy. Explain that as they go through the next few slides reviewing each stage, they should use the space provided on their handout (“Stages of Decomposition”) to depict the content visually. Encourage students to use an animal or human body as the main image. Once students are prepared, transition through the stages of decomposition with slides 23-26 in as much detail as needed. When reviewing the image of the fly cycle, it goes as follows, clockwise from left to right eggs, larva, pupa, adult. After reviewing the content on slide 26, ask for any student volunteers to share their comic strips. 

Transition through slides 27-29 to review which insects appear at each decomposition stage. Emphasize how their presence or absence helps forensic scientists determine PMI (post-mortem interval). For example, when scientists see the hide beetle, they know that the flies have already come and gone and that the body is in a late stage of decomposition.

Display slide 30 and explain to students that now that they have reviewed how insects are used in forensic entomology, they will see how someone in the field applies this knowledge. Show the ICAP video: Crime Solving Insects with Michael Chism.

Michael Chism discusses his job, which uses dermestid beetles to clean skulls and carcasses and explains how he was led into this career. After they view the video, move to slide 31 and review what educational paths students can take to apply the skills they are learning about forensic entomology to the career they just learned about. 

Divide students into small groups and distribute “Case 1” folders (see the Designing the Case Folders handout). Explain that you will model “Case 1” while reviewing forensic entomology. Give each student a Detective Notes handout. Display slide 32 and allow students time to review the materials. Then, invite students to place everything to the side or center of their group making sure to keep the bag of “evidence” still sealed closed. Next, lead a discussion using slide questions. Instruct students to take notes on the Forensic Guided Entomologist Notes handout.

Transition through slides 33-34 and review insect succession. On slide 33, the table depicts which insects appear at which state of the body decomposition. Highlight that blow flies are the first to arrive, as this is relevant to the case studies. Next, move to slide 35 and have students find their Case Resources handout from the folder. Facilitate a class discussion using the questions on the slide. 

Transition through slides 36-37 to review other factors that impact a PMI (postmortem index). Again, remind students to continue to take notes on the Guided Notes handout as you work through the slides. When reviewing slide 37, remind students that not only temperature but also the presence of drugs will affect the development of fly larvae and increase or decrease the estimated PMI. Move to slide 38 and have students read through the Case Card for “Case 1.” Have them measure their evidence. Allow students time to work through the questions with their group before asking for volunteers to answer the questions. Answer questions, ask clarifying questions/evidence to support their answers, and then clear up any misconceptions. Then move to slide 39 and go over the answers. 

Have students return all materials to their Case Folder and turn them in before moving to the Extend.