Safety and evidence boundary
Use supplied long-term ecological datasets and low-risk simulations. Do not manipulate wild populations, introduce species, enter unsafe field sites, or infer a single cause from correlation alone. Population models are approximations with explicit scale and boundary assumptions.
Explicit science instruction
Competition occurs when organisms reduce one another's access to limiting resources. Predation can create coupled population responses, but weather, disease, migration, vegetation and age structure also matter. Predator–prey models simplify these interactions into rates.
Worked example with reasoning
In a fictional 20-year series, prey rises first, predator rises two years later, then prey declines. The lag is consistent with coupled dynamics, but correlation alone cannot exclude climate-driven changes affecting both.
Guided question
What additional evidence would strengthen a predator-causes-prey-decline claim?
Independent work
- Graph paired predator/prey series.
- Identify lags.
- List direct and indirect mechanisms.
- Propose two alternative explanations.
Misconception check
Predator and prey cycles are not synchronized clocks; real populations often show irregular, multi-causal dynamics.
Formative understanding check
Does a lagged correlation prove causation?
Worked response
No. It is evidence of association that must be combined with mechanism and alternative tests.
Open-book formative practice only; not an official mastery attempt or grade.
Mentor evidence conference
Ask Archaemenes to challenge your systems model, quantitative interpretation, alternative explanations, and boundary conditions.
Open ArchaemenesTeacher guidance
Foundation: use a two-line graph. Core: interpret lag cautiously. Extended: compare interaction models with external-driver models.
Preserve learning evidence
Keep models, calculations, graphs, corrections and uncertainty notes in the matching Week 33 evidence field.