Chapter 26- Speciation

Question 0

Species

Answer 0

An evolutionarily independent population or groyp of populations.

Question 1

Speciation

Answer 1

A splitting event that creates two or more distinct species from a single ancestral group.

Question 2

Genetic Isolation

Answer 2

The isolation of a population’s genes due to a lack of gene flow.

Question 3

Genetic Divergence

Answer 3

When selection, genetic drift, and mutation act independently upon isolated populations.

Question 4

Biological Species Concept

Answer 4

Species are indentified by reproductive isolation. Populations are of different species if they are unable to produce offspring with each other.

Question 5

Reproductive Isolation

Answer 5

The inability of two isolated populations to interbreed.

Question 6

Prezygotic Isolation

Answer 6

Prevents individuals from different species from mating.

Question 7

Postzygotic Isolation

Answer 7

The offspring of matings between members of different species do not survive or reproduce.

Question 8

Temporal Isolation

Answer 8

Populations are isolated because they breed at different times.

Question 9

Habitat Isolation

Answer 9

Populations are isolated because they breed in different habitats.

Question 10

Behavioral Isolation

Answer 10

Populations do not interbreed because their courtship displays differ.

Question 11

Gametic Barrier

Answer 11

Matings fail because eggs and sperm are incompatible.

Question 12

Mechanical Isolation

Answer 12

Matings fail because male and female reproductive structures are incompatible.

Question 13

Hybrid Viability

Answer 13

Hybrid offspring do not develop normally and die as embryos.

Question 14

Hybrid Sterility

Answer 14

Hybrid offspring mature but are sterile as adults.

Question 15

Morphospecies Concept

Answer 15

Species are identified by differences in size, shape, or other morphological features.

Question 16

Cryptic Species

Answer 16

Species that differ in traits other than morphology.

Question 17

Morphology

Answer 17

The physical form and appearance of an individual.

Question 18

Phylogenetic Species Concept

Answer 18

Identifies evolutionarily independent lineages by reconstructing the evolutionary history of populations.

Question 19

Monophyletic Group/Clade/Lineage

Answer 19

Consists of an ancestral population, all of its descendents, and only those descendents.

Question 20

Synapomorphy

Answer 20

A trait found in certain groups of organisms that exists in no others.

Question 21

Common Ancestry

Answer 21

The sharing of an ancestral species.

Question 22

Phylogenetic Trees

Answer 22

A branching diagram of the connections between ancestral and descendent species.

Question 23

Phylogeny

Answer 23

A family tree of ancestral species and their descendents.

Question 24

Subspecies

Answer 24

Populations that live in discrete geographic areas and have distinguishing features but not distinct enough to be considered a separate species.

Question 25

Endangered Species Act

Answer 25

A law whose goal is to prevent the extinction of species.

Question 26

Allopatry

Answer 26

When populations live in different areas.

Question 27

Allopatric Speciation

Answer 27

Speciation that begins with physical isolation.

Question 28

Vicariance

Answer 28

A physical splitting of habitat.

Question 29

Dispersal

Answer 29

The spreading of a population to a new habitat, where they colonize it and found a new population.

Question 30

Biogeography

Answer 30

The study of how species and populations are are distributed geographically.

Question 31

Colonization

Answer 31

The migration of a population to a new area where a new population is founded.

Question 32

Sympatry

Answer 32

When populations live close enough to make interbreeding possible.

Question 33

Sympatric Speciation

Answer 33

Speciation that occurs even though gene flow is possible.

Question 34

Disruptive Speciation

Answer 34

Natural selection that selects for the extreme phenotypes on the phenotypic scale.

Question 35

Polyploidy

Answer 35

The condition that mutant individuals have more than two sets of chromosomes.

Question 36

Nondisjunction

Answer 36

The failure of chromosomes to split during meiosis or mitosis.

Question 37

Triploid

Answer 37

Having three chromosomes.

Question 38

Tetraploid

Answer 38

Having four chromosomes instead of two.

Question 39

Autopolyploidy

Answer 39

Individuals with twice the amount of chromosomes from the same species.

Question 40

Allopolyploid

Answer 40

Individuals with double the number of chromosomes from parents of two different species.

Question 41

Self Fertilization

Answer 41

When a parent can fertilize their own eggs.

Question 42

Reinforcement

Answer 42

Selection for traits that isolate populations because hybrid offspring are a wasted effort of the parents and individuals who do not interbreed produce more viable offspring.

Question 43

Hybrid Zone

Answer 43

A geographic area where interbreeding occurs and hybrid offspring are common.

Question 44

Mitochondrial DNA

Answer 44

DNA that is maternally inherited in most animals and plants and can be used to determine the parent species of hybrids.

Question 45

Fusion of Populations

Answer 45

Two populations freely interbreed

Question 46

Backcrossing

Answer 46

Mating hybrids with a member of one of their parent species.

Question 47

Secondary Contact

Answer 47

When two populations come into contact with each other.

Question 48

Hybridization

Answer 48

The creation of hybrids between two species.