Lecture #1: Intro to the Tree of Life

Question 1

LO #1: define phylogeny

Answer 1

figures that represent the ancestor-descendant relationships among a group of organisms

Question 2

LO #2: Explain how speciation is reflected in phylogenies

Answer 2

B/c the basic model of speciation is that the ancestral lineage (A) splits into exactly 2 descendants B + C, and phylogenies are meant to reflect that relationship of splitting

Question 3

LO #3: Provide examples of the use of phylogeny in biology and human society

Answer 3

to show relationships b/w certain species; closest relative/sister taxa (idek about this one sis)

Question 4

Draw a model phylogenetic tree and label its features

Answer 4

Draw a tree (use the example from class)

Question 5

Features of a phylogenetic tree (1-6)

Answer 5

1. taxa/taxon(p)
2. nodes
3. branches
4. root branch
5. time
6. root node

Question 6

at the tips of a phylogenetic tree

Answer 6

taxa/taxon

Question 7

any named group

Answer 7

taxon (relates to taxa)

Question 8

MRCA of 2+ descendant taxa

Answer 8

branches

Question 9

leads to the root node: MRCA of all descendant taxa on the phylogeny

Answer 9

root branch

Question 10

proceeding nodes that represent earlier speciation events

Answer 10

time

Question 11

why do we use phylogenies?

Answer 11

• provide evolutionary perspective
• map characteristics to map evolutionary process and make predictions
• understand origin and our place in the tree of life

Question 12

MRCA of all descendant taxa on the phylogeny

Answer 12

root node