Chapter 20

Question 1

Phylogeny

Answer 1

The evolutionary history of a species or group of species

Question 2

Taxonomy

Answer 2

Naming or classifying scientifically

Question 3

Bio nominal nomenclature

Answer 3

Two-part format of the scientific name

• name italicized
• first letter of genus capitalized

Genus species

Question 4

Name the taxa in Linnaean classification

Answer 4

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

Question 5

Phylogenic tree

Answer 5

Branching diagram representing evolutionary history of a group of organisms

Question 6

Branch points

Answer 6

Divergence of two or more taxa

Question 7

Sister taxa

Answer 7

Groups of organisms that share an immediate common ancestor

Question 8

Basal taxon

Answer 8

A lineage that diverges from all other lineages in its group early in history

Question 9

Polytomy

Answer 9

A branch point from which more than two descendant groups emerge. This signifies that evolutionary relationships among the taxa are not yet clear.

(Not enough evidence to say which are closer related)

Question 10

Analogy

Homoplasies

Answer 10

Similarities between two species that is due to convergent evolution rather than descent from a common ancestor with the same trait.
-caused by similar environments and natural selection producing similar adaptations in different organisms

-analogous structures that arose independently

Question 11

Cladistics

Clades

Answer 11

Common ancestry is the primary criterion used to classify organisms.(setting up branch points to show shared traits)

Groups of cladistics, each of which includes an ancestral species and all of its descendants

Question 12

Shared ancestral character

And

Shared derived character

Answer 12

A character that originated in an ancestor of the taxon (backbone in mammals)

An evolutionary novelty unique to a Clade (hair, shared by all mammals but not in ancestors)

Question 13

Maximum parsimony

Answer 13

A principle that states that when considering multiple explanations, one should first investigate the simplest explanation

Question 14

Molecular clock

Answer 14

An approach for measuring the absolute time of evolutionary change based in the observation that some genes and other regions of the genomes appear to evolve at a constant rate.
*# of nucleotide substitutions in related gene is proportional to the time that has gone by.

Question 15

Horizontal gene transfer

Answer 15

Process where genes are transferred from one genome to another through exchange of plasmids, viral infection or fusion of gametes

Question 16

Systematics

Answer 16

Uses information from Fossils, anatomy and DNA to infer evolutionary relationships.

Question 17

Homologies

Analogies

Answer 17

Phenotypic and genetic similarities due to shared ancestry
Ex: human arm, dolphin flipper, bat wing, bird wing

Cause confusion in developing phylogenies
Ex: insect wing and bat wing did not come from similar ancestor.

Question 18

Monophyletic group

Answer 18

-all relevant groups of organisms must have a common ancestor

Question 19

Paraphyletic group

Answer 19

Doesn’t include all from common ancestor (incomplete)

Question 20

Polyphyletic group

Answer 20

Some look or behave similarly but are not from same common ancestor.