1: Phylogeny & Cladistics

Question 1

Define taxonomy

Answer 1

The discipline of naming and categorizing organisms, based on shared traits

Question 2

Who created/standardized the Binomial Naming System?

Answer 2

Carolus Linnaeus

Question 3

Define phylogeny

Answer 3

The evolutional history of a species or group of related species

Question 4

What is the function of phylogenetic trees?

Answer 4

Diagrams the evolutionary relationships between organisms

Question 5

Define systematics

Answer 5

A discipline that classifies organisms and determines their evolutionary relationships

Question 6

What are some ways that systematists use to infer evolutionary relationships?

Answer 6

• Fossils
• morphological data
• biochemical data (proteins)
• genetic data

Question 7

In a phylogenetic tree, what is the function of a branch point?

Answer 7

Represents the divergence of two species from a common ancestor

Question 8

Define taxon

Answer 8

A type of group - like a species, family, or class

Question 9

Define sister taxa

Answer 9

Groups that share an immediate common ancestor

Question 10

What is a rooted tree?

Answer 10

A phylogenetic tree that includes a branch that represents the last common ancestor of everyone on the tree

Question 11

Define outgroups

Answer 11

A group that is more distantly related to the other groups serving as reference

Question 12

Define a polytomy

Answer 12

A branch where more than two groups diverge, creates an unknown level of closeness

Question 13

Define homologies

Answer 13

Phenotypic and genetic similarities due to shared ancestry

Question 14

A phylogeny must show similarities due to _______

Answer 14

Homology

Question 15

What is the difference between homology and analogy?

Answer 15

Homology: Common ancestor, in structures they are similar but different function
Analogy: No common ancestor (convergent evolution), in structures they are different but similar function

Question 16

Define clades/a clade

Answer 16

Clades are groups of related species, while a clade is a group of species that includes an ancestor and all its descendants

Question 17

Define cladistics

Answer 17

Classifies organisms into groups by common descent

Question 18

Define monophyletic groups

Answer 18

Consists of an ancestral species and all of its descendants

Question 19

Define paraphyletic groups

Answer 19

Consists of an ancestral species and some of its descendants

Question 20

Define polyphyletic groups

Answer 20

Consists of an ancestral species and its descendants plus members not apart of the group

Question 21

What is a shared ancestral character?

Answer 21

A trait that originated from an ancestor

Question 22

What is a shared derived character?

Answer 22

A trait in a clade that is not found in the ancestor