Week 9 Briefing: Arms races
Whether the sanctioning and cheating-detection mechanisms from weeks 2–6 can honestly be called an arms race on the evidence a semester can show.

Rajarshi Rit · CC BY 4.0 · Wikimedia Commons
Case file 09
Case file 09- Date
- 19 April 2027
- Metaphor
- Arms races — escalating measures and countermeasures between opposed interests
- Phenomenon
- Coevolution between exploitative strategies and the partner-choice and sanctioning mechanisms that oppose them
Before the session#
Reread your week-4 or week-6 notes with one question in mind: what would the fungus need to evolve to stop this from happening, and is there evidence it has?
In the session#
Build the coevolutionary story explicitly, step by step, and mark which steps are observed directly and which are inferred from present-day defence mechanisms alone.
Afterwards#
Keep the observed/inferred distinction from this week active for the rest of semester — it recurs in week 11’s case study and in the Peace Conference.
The spec
What you bring to the session. Written so a reader can tell whether it has been met without asking you.
- you can connect one week-4 or week-6 example to a plausible selective pressure it places on the fungal partner
- you can state why "arms race" implies a timescale this course's evidence cannot directly show
Teaching team
- Dr. Marguerite Osei — convenor
- Tobias Lindqvist — tutor