Chapter 26: Phylogeny And The Tree Of Life

Question 1

Phylogeny

Answer 1

The evolutionary history of a species or group of related species

Question 2

Systematics

Answer 2

A scientific discipline focused on classifying organisms and determining their evolutionary relationships

Question 3

Phylogenetic tree

Answer 3

A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms

Question 4

Three domains

Answer 4

Archaea, Bacteria, Eukarya

Question 5

Branch Point

Answer 5

the representation on a phylogenetic tree of the divergence of two or more taxa from a common ancestor

Question 6

Evolutionary Lineage

Answer 6

The sequence of ancestral organisms leading to a particular taxon; represented by a branch in a phylogenetic tree

Question 7

Homologies

Answer 7

Similarity in characteristics resulting from a shared ancestry

Question 8

Analogy

Answer 8

Similarity between two species that is due to convergent evolution rather than descent from a common ancestor with the same trait.

Question 9

Sister Taxa

Answer 9

Groups of organisms that share a common ancestor that is not shared by any other group

Question 10

Cladistics

Answer 10

An approach to systematics in which organisms are placed into groups called clades based primarily on common descent

Question 11

Clades

Answer 11

A group of species that includes an ancestral species and all of its descendants. A clade is equivalent to a monophyletic group

Question 12

Monophyletic

Answer 12

Pertaining to a group of taxa that includes the taxa and all of its descendants

Question 13

Shared ancestral character

Answer 13

A character, shared by members of a particular clade, that originated in an ancestor that is not a member of that clade

Question 14

Shared Derived character

Answer 14

An evolutionary novelty that is unique to a particular clade

Question 15

Outgroup

Answer 15

A species or group of species from an evolutionary lineage that is known to have diverged before the lineage that contains the group of species being studied. An outgroup is selected so that its members are closely related to the group of species being studied, but not as closely related as any study group members are to each other.

Question 16

In group

Answer 16

A species or group of species whose evolutionary relationships are being examined in a given analysis

Question 17

Maximum Parsimony

Answer 17

The principle that when considering multiple explanations for an observation, one should first investigate the simplest explanation that is consistent with the facts

Question 18

Maximum likelihood

Answer 18

As applied to DNA sequence data, a principle that states when considering multiple phylogenetic hypothesis, one should take into account the hypothesis that reflects the most likely sequence of evolutionary events, given certain rules about how DNA changes over time

Question 19

Orthologous Genes

Answer 19

Homologous genes that are found in different species because of speciation, or the formation of new species from a common ancestor

Question 20

Paralogous genes

Answer 20

Homologous genes that are found in the same genome as a result of gene duplication