How to Use This Simulation

Step 1: Use the slider to set the starting energy from producers (plants).

Step 2: Watch how energy decreases at each trophic level - only 10% transfers up!

Step 3: Try the preset scenarios to see real ecosystem examples.

Key concept: 90% of energy is "lost" to heat, waste, and uneaten parts at each level!

🔬 Predict-Observe-Explain Protocol

  1. PREDICT: Before you start, write: What happens to energy at each trophic level as you move up the pyramid?
  2. OBSERVE: Run the simulation and record how much energy transfers between levels.
  3. EXPLAIN: Compare your prediction to the results. Explain the pattern using the 10% rule—why does energy decrease at each level?

Set Producer Energy

10,000 kcal

Energy Pyramid

Energy at Each Trophic Level

Level Organisms Energy % of Original

Where Does the 90% Go? (Energy Loss at Each Level)

Heat (metabolism)
60%
Waste (feces, urine)
25%
Uneaten parts
5%
Stored in body (transferred)
10%

Key Insight

With 10,000 kcal from producers, only 10 kcal reaches apex predators at the 4th trophic level. That's only 0.1% of the original energy! This is why there are always fewer predators than prey - there simply isn't enough energy to support large predator populations.

Check Your Understanding

If a grassland ecosystem has 20,000 kcal of energy from producers, how much energy is available to tertiary consumers (level 4)?