Neighbor's Relation Method Variant of UPGMA that pairs species in a way that creates a tree with minimal overall branch lengths Pairs of sequences separated by only 1 node are said to be neighbors. single central branch a e terminal branches D For this tree topology dac dbd= daD + dbc=a+b+C+d+ 2e=dAB dcD +2e For neighbor relations, four-point condition will be true dAB +dcd dac dBD ..and. daB+ dcd daD dBc So just have to consider all pairwise arrangements and determine which one satisfies the four-point conditionNeighbor’s Relation Method Variant of UPGMA that pairs species in a way that creates a tree with minimal overall branch lengths. Pairs of sequences separated by only 1 node are said to be neighbors. A B C D a b c d e terminal branches single central branch For this tree topology dAC + dBD = dAD + dBC = a + b + c + d + 2e =dAB + dCD +2e For neighbor relations, four-point condition will be true: dAB + dCD < dAC + dBD …and…dAB + dCD < dAD + dBC So just have to consider all pairwise arrangements and determine which one satisfies the four-point condition