The document discusses two primary data types for constructing phylogenetic trees: morphological character data and DNA sequence data. Morphological data involves grouping organisms based on shared physical features, while DNA sequence data helps identify similarities at a genetic level. Additionally, it presents a framework for constructing trees with defined characters and describes the inference process in evolutionary patterns, emphasizing the potential for multiple explanations.

1. Two Types of Data for Constructing Trees There are two major different types of data that can
be used to construct phylogenetic trees. One type of data is morphological character data. Using
this approach, trees are constructed based on the similarities in morphology that organisms share
with each other. For instance, conceptually you would group humans and chimps together
because they share many morphological features, and then you would place gorillas outside of
this group, because gorillas share fewer features than humans and chimps. Another major type of
data is DNA sequence data. A. Morphological Character-Based Parsimony Trees Create a matrix
of characters, listing characters possessed by each organism (where 0 = ab se n t and 1 = present
for each character). We can then identify organisms with similar characters and build a tree using
the data presented in the matrix. Definitions: Chordate = has a spinal column with nerves
Tetrapods = has four legs Amniotes = has an additional sac around the Diapsid condition with
Synapsid condition with embryo (Amniotic Egg) Single Jaw Bone = mammals have one
continuous jaw bone, but many other chordates have multiple bones in Modified from Kardong,
1998 their jaws (like 5 or 6 ). Diapsids = have two holes on the side of their head (see figure
above). Humans, and many other chordates, have only one hole in the side of our head (you can
feel it on your temple when you chew): 6) Look at the Character #8 (warm blooded). Redraw
your tree exactly as you drew it above, but add character #8 to the tree. Is there more than one
possibility with how character #8 is mapped on the tree? What explanation do you have for this
evolutionary pattern? Remember that constructing trees is an inference process, so there may be
several explanations for the observed evolutionary pattern. (hint: think of loss and/or gain of
characters mapped on the tree) (10 pts.) 1) Build a tree using characters 1 through 7 , but don't
use Character #8 (warm blooded) just yet. Map characters 1-7 on your tree (similar to Fig 4.15
in textbook). (hint: identify characters that organisms share. Shared characters allow you to
group taxa into nested sets. See section 4.3 in textbook) (10 pts.)