Alternative phylogenetic methods applied to a five-taxon problem:
Is the Giant Panda (Ailuropoda) more closely related to the Red Panda (Ailurus) or the Brown Bear (Ursus)?

    (1) UPGMA phenogram, equality of branch lengths assumed, (2) Neighbor-Joining, with inferred distances along each branch, (3) NJ Radiation phenogram, without implicit rooting, (4) Maximum Parsimony, with inferred number of SNP changes along each branch, and (5) Maximum Likelihood, with probabilities of changes along each branch.

    Figures 2, 4, & 5 are rooted with Felis, which is known to be in a different suborder than the others. Comparing the UPGMA and NJ phenograms, note that the lengths of the internal branches are approximately the same, as are the terminal branches. The length of the Felis branch is 803 + 386 = 1189, which is about the same as the Procyon branch. Note that the UPGMA, NJ rooted and unrooted networks have the same topology. Note that NJ distances and MP numbers are roughly the same values on terminal branches, but internal branches are quite different.

    All methods agree, that the Giant Panda is more closely related to Ursus than to the Red Panda.

UPGMAUPGMA

Neighbor Joining rootedNJ rooted
Neighbor Joining (unrooted)NJ
          unrooted

 Maximum ParsimonyMP
Maximum Likelihood ML


Figures & Text ©2024 by  Steven M. Carr