Lecture 2

Question 1

What is the chief mechanism of evolution that was discovered by Darwin and Wallace?

Answer 1

natural selection

Question 2

What was the two main ideas Darwin and Wallace proposed?

Answer 2

• all organisms have descended with modification from common ancestors. All species share common ancestory
• the major agent of modification is natural selection operating on variation among individuals (provided a mechanism)

Question 3

What is a phylogeny similar to?

Answer 3

a family tree

Question 4

What do internal nodes tell us?

Answer 4

ancestral taxa, that are extinct

Question 5

What are terminal nodes?

Answer 5

contemporary taxa, which are living and alive ogranisms (tips)

Question 6

True or False: taxa can be rotated around nodes and still depict the same relationships

Answer 6

True

Question 7

What are the types of phylogenetic trees?

Answer 7

• monophyletic group
• paraphyletic group
• polyphyletic group

Question 8

What is a monophyletic group?

Answer 8

includes an ancestor and all of its descendants

Question 9

What is a paraphyletic group

Answer 9

includes ancestor and some, but not all of its descendents

Question 10

what is a polyphyletic group

Answer 10

includes two convergent descendents but not their common ancestor

Question 11

what is another word for a monophyeltic group?

Answer 11

a clade