Ch. 17 Processes Of Evolution

Front 1

Abundance of any particular allele among members of a population

Back 1

Allele Frequency

Front 2

All the alleles of all the genes in a population; a pool of genetic resources.

Back 2

Gene Pool

Front 3

Mutation that alters phenotype so drastically that it causes death.

Back 3

Lethal Mutation

Front 4

Change in an allele's frequency in a population.

Back 4

Microevolution

Front 5

A mutation that has no effect on survival or reproduction.

Back 5

Neutral Mutation

Hint 5

Example: attached earlobes, freckles, red hair.

Front 6

A group of organisms of the same species who live in a specific location and breed with one another more often than they breed with members of other populations.

Back 6

Population

Front 7

Theoretical state in which an allele's frequency never changes in a population's gene pool.

Back 7

Genetic Equilibrium

Front 8

Mode of natural selection in which phenotypes at one end of a range of variation are favored.

Back 8

Directional Selection

Front 9

Mode of natural selection in which traits at the extremes of a range of variation are adaptive, and intermediate forms are not.

Back 9

Disruptive Selection

Front 10

Mode of natural selection in which an intermediate form of a trait is adaptive, and extreme forms are not.

Back 10

Stabilizing Selection

Front 11

Maintenance of two of more alleles of a gene at high frequency in a population.

Back 11

Balanced Polymorphism

Front 12

Natural selection in which a trait's adaptive value depends on its frequency in a population.

Back 12

Frequency-dependent Selection

Front 13

Difference in appearance between males and females of a species.

Back 13

Sexual Dimorphism

Front 14

Mode of natural selection in which some individuals outreproduce others of a population because they are better at securing mates.

Back 14

Sexual Selection

Front 15

Reduction in population size so severe that it reduces genetic diversity.

Back 15

Bottleneck

Front 16

Refers to an allele for which all members of a population are homozygous.

Back 16

Fixed

Front 17

After a small group of individuals found a new population, allele frequencies in the new population differ from those in the original population.

Back 17

Founder Effect

Front 18

The movement of alleles into and out of a population.

Back 18

Gene Flow

Front 19

Change in allele frequency due to chance alone.

Back 19

Genetic Drift

Front 20

Mating among close relatives.

Back 20

Inbreeding

Front 21

The end of gene flow between populations.

Back 21

Reproductive Isolation

Front 22

Evolutionary process in which new species arise.

Back 22

Speciation

Front 23

Speciation pattern in which a physical barrier ends gene flow between populations.

Back 23

Allopatric Speciation

Front 24

Speciation pattern in which populations speciate while in contact along a common border.

Back 24

Parapatric Speciation

Front 25

Speciation pattern in which speciation occurs within a population, in the absence of a physical barrier to gene flow.

Back 25

Sympatric Speciation

Front 26

A burst of genetic divergences from a lineage gives rise to many new species.

Back 26

Adaptive Radiation

Front 27

The joint evolution of two closely interacting species; each species is a selective agent for traits of the other.

Back 27

Coevolution

Front 28

Evolutionary adaptation of an existing structure for a completely new purpose.

Back 28

Exaptation

Hint 28

Feathers for flight are related to insulating feathers in dinosaurs.

Front 29

Refers to a species that no longer has living members.

Back 29

Extinct

Front 30

An evolutionary adaptation that gives its bearer the opportunity to exploit a particular environment much more efficiently or in a new way.

Back 30

Key Innovation

Front 31

Large-scale evolutionary patterns and trends.

Back 31

Macroevolution

Front 32

A macroevolutionary pattern in which a lineage persists with little or no change over evolutionary time.

Back 32

Stasis

Front 33

Quantifiable, heritable chracteristic or trait.

Back 33

Character

Front 34

A group whose members share one or more defining derived traits.

Back 34

Clade

Front 35

Making hypotheses about evolutionary relationships among clades.

Back 35

Cladistics

Front 36

Evolutionary tree diagram that shows evolutionary connections among a group of clades.

Back 36

Cladogram

Front 37

A novel trait present in a clade but not in the clade's ancestors.

Back 37

Derived trait

Front 38

Diagram showing evolutionary connections.

Back 38

Evolutionary Tree

Front 39

An ancestor in which a derived trait evolved, together with all of its descendants.

Back 39

Monophyletic Group

Front 40

Evolutionary history of a species or group of species.

Back 40

Phylogeny

Front 41

The two lineages that emerge from a node on a cladogram.

Back 41

Sister Groups

Front 42

List the 5 conditions that must be met to maintain genetic equilibrium.

Back 42

1. Population must be very large

2. No gene flow between populations

3. Mutations never occur

4. Mating is random

5. No natural selection. All individuals survive and reproduce the same number of offspring.

Front 43

Mechanism of reproductive isolation in which individuals live in different places so they never meet up for sex.

Back 43

Ecological Isolation

Hint 43

Example: two species of garter snake. One lives on land and the other in water.

Front 44

Mechanism of reproductive isolation in which individuals reproduce at different times.

Back 44

Temporal Isolation

Hint 44

Example: Different breeding seasons for the eastern spotted skunk and the western spotted skunk.

Front 45

Mechanism of reproductive isolation in which individuals ignore or do not get the required cues for sex.

Back 45

Behavioral Isolation

Hint 45

Example: elaborate courtship ritual specific to species, specific songs or displays.

Front 46

Mechanism of reproductive isolation in which physical incompatibilities prevent individuals from interbreeding.

Back 46

Mechanical Isolation

Hint 46

Example: different pollinators in plant species only fertilize certain plants species.

Front 47

Mechanism of reproductive isolation in which molecular incompatibilities prevent gametes of a different species from forming a zygote.

Back 47

Gamete Incompatability

Hint 47

Example: Incompatability of the surface proteins in gametes between red and purple sea urchins do not fuse.

Front 48

Mechanism of reproductive isolation in which hybrid embryos die early or new individuals die before they can reproduce.

Back 48

Hybrid Inviability

Hint 48

Example: ligers have more health problems and shorter life expectancy.

Front 49

Mechanism of reproductive isolation in which hybrid individuals or their offspring do not make functional gametes.

Back 49

Hybrid Sterility

Hint 49

Example: Mules cannot interbreed with one another.

Front 50

An evolutionary adaptation that gives its bearer the opportunity to exploit a particular environment much more efficiently or in a new way.

Back 50

Key Innovation

Hint 50

Example: the evolution of lungs.