1. Solanicephala
“Spudheads”

2. Cephalochiridum (aka “head-arm”)
Characters
Present
Absent
Character States
Cephalochiridum (aka “head-arm”)

3. Characters
Present
Present
Absent
Eyes

4. Taxon/Character Matrix

5. Characters
We have different states for the same character, which represent the products of descent with modification
BUT, How can we tell which was the ancestral condition and which is the derived state?

6. Outgroup
A “Stand In” for the Ancestor

7. Three Possible Trees A B C D A C B D
Tree 1
Tree 2 A D C B
Tree 3

8. Mapping Characters A B C D A C B D A D C B 2 changes 1 change Tree 1
Head-arm
loss
2 changes
Tree 3

9. Mapping Characters A B C D A C B D A D C B 1 + 2 = 3 changes
loss
Tree 2
loss
Tree 1 A D C B
Head-arm
loss
Eyes
loss
2 + 1 = 3 changes
Tree 3

10. Results from Initial Analysis?

11. A C B D A B C D A D C B loss loss loss 8 10 11 Tree 1 Tree 2 Tree 3
Head-arm
Ears
Mustache
Loss of Feet
Eyes
Nose
Arms

12. Results with Internal Anatomy?

13. A C B D A B C D A D C B loss loss 11+ 4 = 15 8 + 4 = 12 10 + 2 = 12
Tree 1
Tree 2
Tree 3
Internal Teeth
Internal Tongue

14. Results with Molecular Data?

15. A C B D A B C D A D C B loss loss loss loss 15 + 4 = 19 12 + 2 = 14
= 16
Tree 1
Tree 2
Tree 3
Nucleotide Position 5
Nucleotide Position 10