An Introduction to Phylogenetic Analysis - Association for Biology ...

84 ABLE 2005 Proceedings Vol. 27 Kosinski
Figure 21. The pink label “organisms” arranged alphabetical order. There could be several
different proposals as to how these organisms “evolved.” The bottom nut is glued onto the bolt
to prevent students from removing it.
The parsimonious solution to Exercise E1 is obvious because the cladogram has no homoplasy.
Each organism adds one more derived character to the organism before it in the sequence, as can be seen
from the descriptions above. Therefore, the cladogram is simple:
E A D C B
Figure 22. A parsimonious solution to Ex. E1.
threads
hex nut
flat washer
lock washer
There are several possible solutions when the pink label “organisms” (F-J) are added. One solution
involves two origins of the hex head (for H and I as a pair, and also for F), and loss of a flat washer from
G.