Nonlinear dynamics · Research Worlds
Can a spot make another?
Enter a bright chemical pattern laboratory. Change the feed and watch a numerical reaction field respond.
Free · No account required · Runs in your browser
Watch the 90-second visual story ↗What will you explore?
Pearson, 1993
Simple reactions can sustain complex patterns.
How does it work?
Watch a 90-second cinematic explanation, or explore a story that pauses so you can change its central mechanism. Inspect the source evidence, compare outcomes and resume the narration. This free Lesson Worlds adaptation needs no account or download; younger learners may want help from a parent or teacher.
Inside the cinematic story
Can a spot make another?
Chemical patterns, not cells
Enter the reaction
U + 2V → 3V · V → inert product
Turn the feed
Same seed · change F
Take control: Replay the same initial condition with a different feed rate. F = .020 · F = .040
Change what leaves
Same seed · change k
Take control: Replay the same initial condition with different removal. k = .059 · k = .065
A result with boundaries
Numerical adaptation · explicit limitations
Patterns without a painter
Explore the equations behind the pattern
Discuss the evidence
Before starting, explain what you think this claim means: Simple reactions can sustain complex patterns. After exploring, choose one stage above and describe what its model helps you see. Separate what you observed in the adaptation from what the original researchers measured.
Read the original publication for its methods, evidence and limitations. Ask which part of the explanation the interactive model leaves out, and what additional evidence you would need to test the claim yourself.
Original Gray–Scott numerical adaptation, not a biological experiment or an exact reproduction. Periodic 64×64 grid, domain .64×.64, dx=.01, dt=1, diffusion coefficients 2e-5 and 1e-5, 12×12 seeded perturbation with ±1% noise, 9000 steps. Pearson's main catalog used a 2.5×2.5 domain, 256×256 grid, 20×20 seed and 200000 steps. Surface height and color encode V concentration; the paper colored U. Film time is compressed, not laboratory seconds. No chaos estimate, biological validation or exact pattern classification is claimed.
Original research
Complex Patterns in a Simple System
John E. Pearson · Science 261(5118), 189–192 · 1993
Educational adaptation by Lesson Worlds. Not affiliated with John Pearson, Science or AAAS. The original publication may have its own access terms.