How does one construct a phylogenetic tree that shows a parsimoious relationship between species?

Question

How does one construct a phylogenetic tree that shows a parsimoious relationship between species?

IE:
Species
1 ATG AGC TGC
2 ATT AAC TGC
3 ATG AGC TGC
4 ATT AAC TGC

Answer 1

The principle of parsimony is that the least number of changes is the most likely to have happened. If you drew a phylogeny and put the 4 species on it, you would want them in the order that requires the least number of changes from the species you are comparing them to, probably species 1 in your example. So compare each one (2,3,4) to 1 separately and there should be a difference in the number of changes from species to species. When I say difference, I mean that if a G is substituted by a T, then a change has occurred.