Using maximum parsimony with the outgroup A as ancestral state 0, what is the minimum number of independent gains of state 1 along this tree?
- A
3
- B
1
- C
4
- Dcheck_circle
2
Explanation
With B = 1, C = 0, D = 1, E = 1, you cannot place a single gain on a contiguous clade because C (between B and D/E) is 0. Two independent gains (e.g., on B and on the D-E branch) is the most parsimonious.