Species A Species B Species C Species D Species A 10 40 20 5

Species A Species B Species C Species D Species A 10% 40% 20% 50% 20% ies C ies D Above are some genetic data for four different species. Listed in the table are the percentage differences in the sequences between each pair of species. From these data, select the phylogenetic tree that best captures the relationships among these different groups.

Solution

Ans: Tree C

similarity between species A and B (AB) = 40%

similarity between species A and C (AC) = 10%

similarity between species A and D (AD) = 20%

similarity between species B and C (BC) = 40%

similarity between species B and D (BD) = 50%

similarity between species C and D (CD) = 20%

We can see that Species B and Species D is showing the highest similarity (50%)

So in our tree C we can see Spcies BD originates from the common ancester and the percentage similarity of BA = BC

and percentage similarity of CD = AD

Note: You need little bit analization inorder to understand this relationship between the species and construct a phylogenetic tree. Please try to understand the tree.