Chapter 26: Phylogeny and the Tree of Life

Question 1

Classifies organisms and determines their evolutionary relationships

Uses fossils, molecular, and genetic data to infer evolutionary relationships

Answer 1

Systematics

Question 2

The evolutionary history of a species or group of related species

Answer 2

Phylogeny

Question 3

The order, division, naming and classifying of living and extinct organisms and viruses

Linnaeus introduced this system for grouping species

Answer 3

Taxonomy

Question 4

Each group in taxonomy is called a _______

Answer 4

Taxon

Question 5

The taxonomic groups from broad to narrow are?

Answer 5

Domain, supergroup, kingdom, phylum, class, order, family, genus, and species

Think of dear king Philip came over for green soup. Just add supergroup after domain***

Question 6

What is the two-part scientific naming system called?

Answer 6

Binomial nomenclature

Question 7

What are the requirements when using binomial nomenclature?

Answer 7

• genus name and species epithet
• genus name always capitalized
• species epithet never capitalized
• both names either italicized or underlined
• rules for naming established and regulated by international associations

Question 8

True or false…

Linnaean Classification and phylogeny can differ from each other.

Answer 8

True

Question 9

What does a phylogenetic tree depict?

Answer 9

Evolutionary relationships for a group of organisms

Question 10

What does phylogenetic tree represent?

Answer 10

A hypothesis about evolutionary relationships

Question 11

This represents the divergence of two species

Answer 11

Branch point

Question 12

Groups that share an immediate common ancestor not shared by another group

Answer 12

Sister taxa

Question 13

Includes a branch to represent the last common ancestor of all taxa in the tree

Answer 13

Rooted tree

Question 14

Diverges early in the history of a group and originates near the common ancestor of the group

Answer 14

Basal taxon

Question 15

In a phylogenetic tree, can it be assumed that a taxon evolved from the taxon next to it?

Answer 15

It should not be assumed

Question 16

Phylogenetic trees show patterns of __________, not phenotypic similarities

Answer 16

Decent

Question 17

Do phylogenetic trees indicate when a species evolved or how much change occurred in a lineage?

Answer 17

No.

No time scale

Question 18

How are phylogenies inferred?

Answer 18

Systematics gather information about morphologies, genes, and biochemistry of living organisms

Question 19

In order to determine phylogeny what type of features should systematics focus on?

Answer 19

?

Question 20

What are the phenotypic and genetic similarities due to shared ancestry?

Answer 20

Homologies

Question 21

Similarities do to convergent evolution.

Ex: snakes and the grass lizard. Both do not have legs but they are not from a common ancestor

Answer 21

Analogy

Question 22

When constructing a phylogeny, systematic need to determine whether a similarity is the result of ___________ or _________

Answer 22

Homology or analogy

Question 23

Occurs when similar environmental pressures and natural selection produce similar (analogous) adaptations in organisms from different evolutionary lineages.

Answer 23

Convergent evolution

Ex: ant-eaters and echidnas

Question 24

Analogous structures for molecular sequences that evolved independently

is a character shared by a set of species but not present in their common ancestor. A good example is the evolution of the eye which has originated independently in many different species

Answer 24

Homoplasies

Ex: bird wings and bat wings. They do not have a common ancestor.

Question 25

When organisms are grouped by common dissent

Answer 25

Cladistics

Question 26

A group of species that includes an ancestral species and all of it’s descendants

Answer 26

Clade Can be nested in larger or smaller clades

Question 27

(of a group of organisms) descended from a common evolutionary ancestor or ancestral group, especially one not shared with any other group.

Answer 27

Monophyletic

Question 28

A valid clade is ___________, signifying that it consists of the ancestor species and all of its descendants

Answer 28

Monophyletic

Question 29

A grouping that consists of an ancestral species and some, but not all, of the descendants

Answer 29

Paraphyletic grouping

Question 30

A grouping that Consist of various species with different ancestors

Answer 30

Ployphyletic grouping

Question 31

A shared _________ character is a character that originates in an ancestor of the taxon

Answer 31

Ancestral

Question 32

A shared _________ character is a characteristic with evolutionary novelty unique to a particular clade

Answer 32

Derived

Question 33

A character can be both ancestry and derived depending on the context. True or false?

Answer 33

True

Question 34

In group vs. outgroup?

Answer 34

Ingroup-The various species being studied Outgroup-species or group of species that is assumed to have diverged before the species in the ingroup

Question 35

What does an outgroup lack when compared to an ingroup?

Answer 35

?

Question 36

In some trees, the length of a branch can reflect the number of _________ changes that have taken place in a particular DNA sequence in that lineage

Answer 36

genetic

Question 37

What principles do systematics apply to narrow the possibilities to make the best tree out of large data sets?*

Answer 37

* ** maximum parsimony | * ** maximum likelihood

Question 38

What principle assumes that the tree that requires the fewest evolutionary events is the most likely? (Shared derived characters)

Answer 38

Maximum parsimony

Question 39

Which principle states that, given certain rules about DNA changes over time, a tree can be found that reflects the most likely sequence of evolutionary events?

Answer 39

Maximum likelihood

Question 40

-Result from gene duplication, so are found in more than one copy in the genome -they can diverge within the clade that carries them and often evolve new functions. (Within a species) Ex:globins

Answer 40

Paralogous genes

Question 41

- Genes that are found in a single copy in the genome and are homologous between species - They can diverge only after speciation occurs - widespread and extend across many widely different species

Answer 41

Orthologous genes