Module 4 of 4

The Resolution Limit

Calibrating support across different evolutionary scenarios.

The relationship between Duplicate Stability (Green) and Topological Accuracy (Blue) depends on the shape of the tree.

Select a Topology:
  • Deep Branching (Easy): Strong signal. Topology and duplicates are both robust.
  • Shallow Branching (Hard): Weak signal. The deep topology collapses long before the duplicates do. This shows why the criterion is conservative.
  • Mixed Lengths: Rate heterogeneity. Long branches (A, C) accumulate more noise than short branches (B, D).
Experiment
  1. Select "Shallow Branching".
  2. Increase Noise. Notice the Blue split-support drops while duplicates stay high.
  3. Switch to "Deep Branching".
  4. Notice how much more noise is required to break the split.
← Previous
Reference Topology (8 taxa, no noise)
Pruned Tree (A,B,C,D) — Split Support (100 reps)
Duplicate Cherry Support (100 reps)
A–A′
B–B′
C–C′
D–D′
Duplicate Monophyly ($D$) 100%
A–A′: 100% · B–B′: 100% · C–C′: 100% · D–D′: 100%
Topological Accuracy ($A$) 100%
Support is the frequency of the reference split on the pruned tree.