Which part of the living system did you change?
Labs / Biology
Build a Family Tree
Every branch point unites species by a shared derived trait — a feature they inherited from a common ancestor no other creature has. Drag the species up and down to nest them, and the tool counts how many times each trait had to evolve. The best family tree is the one that needs the fewest changes.
Labs / Biology / Build a Family Tree
Build a Family Tree
Every branch point unites species by a shared derived trait — a feature they inherited from a common ancestor no other creature has. Drag the species up and down to nest them, and the tool counts how many times each trait had to evolve. The best family tree is the one that needs the fewest changes.
Why it matters
Why explore this?
Living systems are connected and constantly changing. This model makes one biological process visible so you can test how its parts affect one another.
Explore
Try the model
changes 0fewest 0clades 0best? no
Investigate
Questions to test
Predict first, try it in the model, then use what you observe to answer.
What to try
- Can you rearrange the branches until the “fewest” number and your “changes” number match? What order puts them there?
- Which trait unites the most species — and which unites just one? Where do those marks land on the tree?
- Turn off “warm-blooded.” Does the best tree change? Why might a trait that evolved twice mislead you?
- Sparrows have feathers and mice have hair, yet both are warm-blooded. Should that shared warmth make them closest cousins?
- Switch off every trait but one. How much can a single character tell you about the whole tree of life?
Explain
Make sense of what happened
Explain the process as a chain: a change happens, the system responds, and that response affects what happens next. Use an observation from the model as evidence.
Check
Before you leave
How did the system respond?
How would you explain that response?
If you can answer all three using evidence from the model, you understand the main idea. If not, return to Explore and change one setting at a time.