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Question 1

what is taxonomy?

Answer 1

the science of identifying, naming, and classifying new species

Question 2

what is binomial nomenclature?

Answer 2

a system in which species are given a two part Latinized name, where the first part identifies and genus and the second part identifies the specific epithet (species name)

Question 3

what are all the groupings in the taxinomical hierarchy?

Answer 3

domain
kingdom
phylum
class
order
family
genus
species

Question 4

what is a taxon?

Answer 4

all the organisms within any category at any level of the taxinomical hierarchy (ex: all organisms within the class Mammalia are one taxon, and all organisms within the genus Ursus are a different taxon)

Question 5

what is a phylogeny?

Answer 5

the evolutionary history of an organism/organisms

Question 6

what is a phylogenetic tree?

Answer 6

branching diagrams that illustrate phylogenies. are formal hypotheses that identify likely relationships among species and higher taxonomic groups

Question 7

what does the root of a phylogenetic tree represent?

Answer 7

the common ancestor of all the species represented in the tree

Question 8

what is anagenesis?

Answer 8

pattern of evolution as gradual change

Question 9

what is cladogenesis?

Answer 9

when one species undergoes speciation, producing two species distinct from each other and their common ancestor

Question 10

do anagenesis and cladogensis increase biodiversity?

Answer 10

anagenesis does not but cladogenesis does

Question 11

what are sister clades?

Answer 11

two clades that originate from the same node

Question 12

what are sister species?

Answer 12

two species that emerge from the same node near the very top of the tree

Question 13

what does it mean when more than two branches originate from a single node?

Answer 13

it indicates the biologists are not yet sure what the exact order and relationship of the branches is yet, these nodes are “unresolved”

Question 14

what is a monophyletic taxon/lineage?

Answer 14

basically a clade. a portion of a tree that consists of an ancestral species and all of its descendants.

Question 15

what is a polyphyletic taxon/lineage?

Answer 15

a taxa that includes organisms from different clades of a phylogenetic tree but not the common ancestor of the clades

Question 16

what is a paraphyletic taxon/lineage?

Answer 16

a taxa that includes a common ancestor and some but NOT ALL descendants

Question 17

what is homology? (homologous characters; homologies)

Answer 17

similarity due to shared ancestors

Question 18

what is convergent evolution?

Answer 18

the evolution of similar adaptations in distantly related organisms that occupy similar environments

Question 19

what is homoplasy? (homoplastic characters; homoplasies)

Answer 19

phenotypic variation that evolved separately, often a product of convergent evolution

Question 20

what is analogy? (analogous characters; analogies)

Answer 20

homoplastic characters that serve similar functions in different species

Question 21

what is traditional systematics?

Answer 21

building phylogenetic trees by focusing on the ends of the branches: assessing amount of phenotypic divergence between lineages, as well as patterns of branching evolution that produced them. focusing on the products of anagenesis and cladogenesis

Question 22

what is cladistics?

Answer 22

an approach that produces phylogenetic hypotheses and classifications that reflect only the branching pattern of evolution and entirely ignores phological diversion by grouping together organisms that shared derived character states

Question 23

what are character states?

Answer 23

character states are the forms (of which there are at least two) that can a character can exist in

Question 24

what is an ancestral character state?

Answer 24

the character state of ancestors of a clade

Question 25

what is an derived character state?

Answer 25

the character state of the descendants of a clade that developed from ancestral character state

Question 26

what is an apomorphy?

Answer 26

a derived character state

Question 27

what is a synapomorphy?

Answer 27

derived character state found in two or more species

Question 28

what are synapomorphies useful for?

Answer 28

they can serve as markers for monophyletic lineages

Question 29

what is outgroup comparison?

Answer 29

the technique of identifying ancestral and derived character states by comparing the ingroup (clade understudy) to those of an outgroup (species that are related to the ingroup but not part of it). characters in outgroup are ancestral and those only in ingroup are derived

Question 30

what is the PhyloCode?

Answer 30

a strictly phylogenetic system of classification of organisms

Question 31

what is the principle of parsimony?

Answer 31

the simplest plausible explanation of any phenomenon is the best (assume complex evolutionary change is an unlikely event--most likely tree is the one w the fewest homoplasies (independent origins of character states))

Question 32

what is a phylogram?

Answer 32

a phylogenetic tree where branch lengths represent the amount of inferred evolutionary change/time

Question 33

what is a cladogram?

Answer 33

a phylogenetic tree where all branches are the same length

Question 34

what is macroevolution?

Answer 34

evolution above the species level

Question 35

what is adaptive radiation?

Answer 35

the rapid evolution of new species occupying new niches