lecture 21

Question 1

character polarity

Answer 1

determines the direction of evolutionary change, or which came first and which evolved after

Question 2

out group method

Answer 2

the out group helps determine the root by acting as a reference point for ancestral traits

Question 3

unrooted trees:

Answer 3

have no specified order origin or direction

Question 4

two ways to look at a tree

Answer 4

1. confidence in the tree overall
2. confidence in each node

Question 5

what do consensus trees do?

Answer 5

summarize agreement across different proposed phylogenies

Question 6

strict consensus tree

Answer 6

only includes clade in the consensus phylogeny that appear in ALL input trees

Question 7

majority rule consensus tree

Answer 7

only include clade that at least 50% of all the input trees support

Question 8

congruence test

Answer 8

sees how well all the data agrees with each other in supporting the same overall evolutionary relationships

Question 9

character support

Answer 9

number of synapomorphies (shared or derived traits) that support each branch

Question 10

bootstrapping

Answer 10

repeated over and over resampling of that data at random to determine how often the clade tested will appear

Question 11

assigning bootstrapping values

Answer 11

number of times clade appeared over the total number of resampled trees

Question 12

liklihood

Answer 12

probability of the data (genomes) given a tree or model

Question 13

hypothesis

Answer 13

history of the tree plus model of evolution