Study Goals Exam 2 Week 4

Question 1

A phylogeny is a hypothesis of evolutionary relationships — does this mean that phylogenies are testable, falsifiable, and have predictive power?

Answer 1

Yes

Question 2

Clades

Answer 2

An evolutionary unit that includes an ancestral species and all of its descendants, but no others

Question 3

Parsimony

Answer 3

Assumes that the most likely explanation or pattern is the one that requires the fewest steps

Question 4

Taxa

Answer 4

Helps describe, name, & classify individual species and higher-level groups

Question 5

Outgroups

Answer 5

A taxon that is not part of the taxonomic group being studied but is closely related

Question 6

Sister Groups

Answer 6

The two descendants that split from the same node and are each other’s closest relatives

Question 7

Nodes

Answer 7

Hypothetical common ancestors before splitting events

Question 8

Branches

Answer 8

-Left more ancient or ancestral
-Right more recent or derived

Question 9

Are homology and synapomorphy?

Answer 9

Yes they are shared, derived traits

Question 10

Homoplasy

Answer 10

A trait appearing not resulting from a shared common ancestor

Question 11

Are all adaptations homologies?

Answer 11

No

Question 12

Are humans chordates or vertebrates?

Answer 12

Chordatas because notochord is developing into a spinal cord

Question 13

Which traits are unique to clade Chordata?

Answer 13

-Notochord
-Dorsal Hollow Nerve Cord
-Pharyngeal Slits
-Post-Anal Tail

Question 14

How are Chordatas (notochord) adaptations?

Answer 14

-Source of midline signals and cues
-Development of the embryo

Question 15

How are Vertebrata (vertebrate) adaptations?

Answer 15

-provides structural support
-facilitates efficient movement across diverse environments

Question 16

How are Gnathostomata (jaws) an adaptation?

Answer 16

-Become mobile predators

Question 17

How are Sarcopterygii (appendages with large bones) an adaptation?

Answer 17

-Movement
-Picking up things
-Hunting/Survival

Question 18

How are Tetrapodas (four limbs with fingers and toes(digits)) an adaptation?

Answer 18

-Transition from aquatic to terrestrial life
-Movement
-Grip

Question 19

How are Amniota (amniotic egg) an adaptation?

Answer 19

-Lay eggs on land
-Allowed animals to move from water to live on land

Question 20

Do humans belong to the clades (chordata, vertebrata, gnathostomata, sarcopterygii, tetrapoda, & amniota) ? How would you know?

Answer 20

Yes we have all these traits

Question 21

How is the concept of parsimony used to determine evolutionary relationships?

Answer 21

When there is no evidence choose the simplest answer, when there is multiple answers choose the simplest one (ex: family relation)

Question 22

What is a homoplasy and how is this concept related to convergent evolution?

Answer 22

A trait appearing not resulting from a shared common ancestor and this is related because it appears through convergent evolution

Question 23

Convergent Evolution

Answer 23

When two or more unrelated species develop similar traits due to being in similar environments