Bio221 - Ch 26

Front 1

Phylogeny

Back 1

The evolutionary history of a species or group of related species.

Front 2

Systematics

Back 2

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

Front 3

Taxonomy

Back 3

A scientific discipline concerned with naming and classifying the diverse forms of life.

Front 4

Binomial

Back 4

A common term for the two-part, latinized format for naming a species, consisting of the genus and specific epithet; also called a binomen.

Front 5

Genus (plural, genera)

Back 5

A taxonomic category above the species level, designated by the first word of a species’ two-part scientific name.

Front 6

Family

Back 6

In Linnaean classification, the taxonomic category above genus.

Front 7

Order

Back 7

In Linnaean classification, the taxonomic category above the level of family.

Front 8

Class

Back 8

In Linnaean classification, the taxonomic category above the level of order.

Front 9

Phylum (plural, phyla)

Back 9

In Linnaean classification, the taxonomic category above class.

Front 10

Kingdom

Back 10

A taxonomic category, the second broadest after domain.

Front 11

Domain

Back 11

A taxonomic category above the kingdom level. The three _____s are Archaea, Bacteria, and Eukarya.

Front 12

Taxon (plural, taxa)

Back 12

A named taxonomic unit at any given level of classification.

Front 13

Phylogenetic tree

Back 13

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

Front 14

Branch point

Back 14

The representation on a phylogenetic tree of the divergence of two or more taxa from a common ancestor. A _____ is usually shown as a dichotomy in which a branch representing the ancestral lineage splits (at the _____) into two branches, one for each of the two descendant lineages.

Front 15

Sister taxa

Back 15

Groups of organisms that share an immediate common ancestor and hence are each other’s closest relatives.

Front 16

Rooted

Back 16

Describing a phylogenetic tree that contains a branch point (often, the one farthest to the left) representing the most recent common ancestor of all taxa in the tree.

Front 17

Basal taxon

Back 17

In a specified group of organisms, a taxon whose evolutionary lineage diverged early in the history of the group.

Front 18

Analogy

Back 18

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

Front 19

Cladistics

Back 19

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

Front 20

Clade

Back 20

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

Front 21

Monophyletic

Back 21

Pertaining to a group of taxa that consists of a common ancestor and all of its descendants. A _____ taxon is equivalent to a clade.

Front 22

Paraphyletic

Back 22

Pertaining to a group of taxa that consists of a common ancestor and some, but not all, of its descendants.

Front 23

Polyphyletic

Back 23

Pertaining to a group of taxa that includes distantly related organisms but does not include their most recent common ancestor.

Front 24

Shared ancestral character

Back 24

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

Front 25

Shared derived character

Back 25

An evolutionary novelty that is unique to a particular clade.

Front 26

Outgroup

Back 26

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 _____ 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.

Front 27

Ingroup

Back 27

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

Front 28

Maximum parsimony

Back 28

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

Front 29

Maximum likelihood

Back 29

As applied to DNA sequence data, a principle that states that when considering multiple phylogenetic hypotheses, 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.

Front 30

Orthologous genes

Back 30

Homologous genes that are found in different species because of speciation.

Front 31

Paralogous genes

Back 31

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

Front 32

Molecular clock

Back 32

A method for estimating the time required for a given amount of evolutionary change, based on the observation that some regions of genomes evolve at constant rates.

Front 33

Horizontal gene transfer

Back 33

The transfer of genes from one genome to another through mechanisms such as transposable elements, plasmid exchange, viral activity, and perhaps fusions of different organisms.