Scene Food web
Ecosystem Motion Loading artwork…
Nutrient supply 100% Nutrient supply 100%
×
Dashed links show competition.
Human intervention Off People repeatedly remove the invader. Recovery takes time.
Try a clear example
In Menu, open Experiments. Copy A’s starting setup to B. Run A without the invader and B with it to step 200 (Play twice), then Compare. To test removal, use the same invaded setup in both and turn Human intervention on in B only.
Included Feeds on
Species info
Feeding sources Starting amount Amount Model units. Reset keeps this amount.
Population × Patterns Step 0 / 2,000
Move across the graph to see step and population at the thin line. Drag on a phone, or use the slider and arrow keys. Leaving the graph returns to the latest step.
Inspect 0
Run advances to the next 100-step mark. Step advances once.
Step 0
Test details At this step, B − A: — model units.
All included organisms appear by default. Choose one in either web or the menu to focus on it. Both graphs use the same scales. A blank value means the species is excluded or that run has not reached this step.
Copy a setup, change one factor, then run both to the same step. Each scenario saves separately in this browser. Download both to keep a separate record.
These results compare a fictional teaching model, not measured populations.
× About this lab Atlantic Ocean · Northwest Atlantic shelf
Choose an ecosystem. Each has its own species and selected feeding relationships.Click a species. Turn it on or off, or change its diet. Arrows point from food to consumer.Run an experiment. Run advances to the next hundred-step mark; Step advances once. Changes pause the model so you can make a prediction.Follow the graph. Move across the graph to see the step and population beside the thin line. Drag on a phone or use the step slider. The data table shows the inspected step’s exact values.Compare. Open Experiments in the Menu. A and B keep separate setups and results. Copy one starting setup to the other, change one variable, and run both. Compare pairs each food web with its graph. All included organisms appear on the graphs. Choose one in either web to focus on it; the shared step slider moves both graphs together on matching axes. On a phone, use Food web beside A or B to reveal its web.Introduce an invader In Food web, open Set up and select Invasive species where available. Click the new species to read what it might change. Make a prediction together, then use the usual Play button. Human intervention in its card represents repeated removal. Solid arrows show native feeding links. Dotted arrows show food energy reaching an invasive consumer. Dashed lines without arrowheads show plant competition, not feeding; invasive plants use sunlight to make food. These are possible model outcomes, not forecasts or guaranteed recovery.
Reading the screen Tap a species portrait to include it or choose its food. Highlighted choices are active. Arrows point from food to consumer. The scene follows the inspected graph step. Each species uses a fixed drawing scale: more or fewer portraits show changes relative to its default abundance. A partially faded portrait represents part of a drawing unit. Pictures are capped to keep the scene readable; graph values are exact model values, not counts of drawn animals.
Relative abundance · model units
How I made this model I built this lab with Codex, OpenAI’s coding assistant, inspired by the original Annenberg Ecology Lab. Feeding relationships draw on published research. Codex selected the equations and numerical settings using established modelling ideas: resource-limited growth, competition, and feeding that levels off as food becomes abundant. These settings were not fitted to measurements of these species. The results illustrate possible patterns within this model; they do not predict real ecosystems.
What the model means These are simplified webs, not complete accounts of each region. Species and diets vary by place, season, and life stage. Plant abundance represents food resources such as leaves, fruit, and seeds. Changes in the artwork illustrate abundance; depth and motion are decorative, not simulated animal behaviour. Use Motion to freeze the scene. Reduced-motion preferences are respected; motion stops offscreen, in background tabs, and while you inspect an earlier step.
Resource controls alter the producers’ carrying capacity. “Rainfall” and “nutrient supply” are teaching controls, not calibrated climate or chemical measurements. A model step is not a real day.
Scenarios A and B save separately for each ecosystem in this browser. Set up offers simple chains to build on, a fuller web, and an empty start. Changing a preset or resetting affects only the current scenario; the other stays saved. CSV, run downloads and Download both scenarios let you keep a separate record. Experiment data stays in your browser. The website counts page views without visitor cookies; it does not collect your experiment data. Runs can reach 2,000 steps. Excluded organisms are hidden from the graph; their recorded data remains in exports. Use Teacher controls in the Menu to unlock starting values or choose Guided or Independent mode. Guided mode adds optional pattern descriptions; both modes use the same equations. For guided questions, open the guided investigation , or read the teacher guide .
Ready
Original inspiration Inspired by Ginger Booth’s Ecology Lab (2015) .
Read the story, assumptions, sources, and APA credits × Teacher controls Choose how much support to reveal. Changing support keeps the current experiment and its equations.
Guided Independent
Guided adds a Patterns button and shades the graph interval it describes. Independent leaves interpretation to the learner.
Starting values Edit starting values Unlock Starting amount inside each species’ details at step 0. Reset keeps the values I choose.
Hints to include Increasing / decreasing Settling / changing little Fluctuating Reached zero Scenario comparison
Settings stay in this browser. For a class link, open Guided or Independent . The link sets the mode; hint choices remain local.