Ecological Succession Simulator
Advance a lifeless rocky landscape through Primary Succession using lichen pioneers. Trigger a catastrophic fire to demonstrate the much faster, soil-rich process of Secondary Succession.
ECOLOGICAL SUCCESSION: REBUILDING THE SYSTEM
Ecosystems are dynamic and constantly changing. **Ecological Succession** is the predictable, orderly change in the composition of species in a community over time, usually following a disturbance.
PRIMARY VS. SECONDARY SUCCESSION
1. **Primary Succession**: Occurs on land where NO soil exists (e.g., after a volcanic eruption or glacier retreat). It begins with **pioneer species** like lichens and mosses that break down rock into soil. 2. **Secondary Succession**: Occurs after a disturbance that leaves the soil intact (e.g., after a forest fire or abandoned farm). It happens much faster because the seed bank and soil are already present.
HOW TO USE THIS VISUALIZATION
1. **Trigger a Disturbance**: Click the 'Volcano' for Primary or 'Fire' for Secondary. 2. **Watch the Clock**: Observe how the community changes over hundreds of virtual years. 3. **Identify Species Types**: Note the transition from r-selected 'weedy' pioneers to K-selected 'climax' forest species. **Try This**: Run the Secondary Succession simulation. Which grows back first: the grasses or the hardwood trees? Why do the trees eventually outcompete the grasses for light?
AP EXAM CONNECTION
Unit: Unit 8: Ecology (Topic 8.5)
Learning Objective: ENE-4.B
COMMON MISCONCEPTIONS
- Thinking succession ends in a 'perfect' state (climax communities are still dynamic).
- Believing secondary succession starts from 'nothing'.
- Assuming only plants undergo succession (animals, fungi, and bacteria do too).
KEY TAKEAWAYS
- Succession is a predictable process.
- Disturbances reset the clock.
- Pioneers create habitat for others.
- Competition drives species turnover.
PRACTICE QUESTIONS
Q1 (CONCEPTUAL): Why does primary succession take hundreds of years longer than secondary succession?
Show Answer & Explanation
Answer: Soil must be created first.
Explanation: Primary succession starts with bare rock, which requires lichens and erosion to create a soil base for plants to grow.
Q2 (CONCEPTUAL): What characterizes a 'climax community'?
Show Answer & Explanation
Answer: A stable, long-term association of species that is not significantly changing over time.
Explanation: A climax community is the final stage of succession where the species composition remains relatively constant until the next major disturbance.
