Biodiversity Test 1

Front 1

natural selection

Back 1

the differential contribution of offspring to the next generation by varous genetic types belonging to the same population.

Front 2

adaptation

Back 2

1) the processes or evolutionary mechanisms that produce useful characteristics, and 2) the characteristics themselves

Front 3

Conditions for Hardy-Weinberg Equilibrium

Back 3

1)Mating is random
2)Population size is infinite
3)There is no gene flow
4)There is no mutation
5)Natural selection does not affect the survival of particular genotypes

Front 4

Hardy-Weinberg Equilibrium Equation

Back 4

P^2 + 2PQ + Q^2 = 1

Front 5

Mechanisms of Evolution

Back 5

1)Mutations generate genetic variation
2)Gene flow may change allele frequencies
3)Genetic drift may cause large changes in small populations
4)Nonrandom mating changes genotype frequencies.

Front 6

stabilizing selection

Back 6

preserves the average characteristics of a population by favoring average individuals.

Front 7

Biodiversity

Back 7

the number of species present in an area

Front 8

Evolution

Back 8

genetic change in a population over time.

Front 9

Population Genetics

Back 9

study of changes in genetic makeup of a population.
Goal: to understand the mechanisms that change allele frequencies.

Front 10

Gene Flow

Back 10

movements of individuals between populations with different allele frequencies

Front 11

Bottlenecks

Back 11

Reduction of population to a small number of individuals

Front 12

Founder Effect

Back 12

Small number of individuals colonize a new habitat

Front 13

Mutation

Back 13

A change in DNA

Front 14

Sexual Selection

Back 14

Organisms with certain physiological traits get more matings.

Front 15

Node

Back 15

point where lineage divides into 2 splits

Front 16

Divergent Evolution

Back 16

Environmental pressures and natural selection lead to organisms in the same lineage developing diverging traits.

Front 17

Convergent Evolution

Back 17

Environmental pressures and natural selection lead to organisms developing similar traits in different lineages.

Front 18

Homologous Traits

Back 18

Similar traits due to a common ancestor

Front 19

Analogous Traits

Back 19

Similar traits due to convergent evolution

Front 20

Derived Traits

Back 20

Traits that are not shared by an ancestor

Front 21

Ancestral Traits

Back 21

Traits inherited from a common ancestor

Front 22

Adaptive radiation

Back 22

genetic differentiation between populations in response to changes in the environment.
- follows mass extinctions
- ex Hawaii

Front 23

Living fossil

Back 23

species that have remained unchanged for millions of years.

Front 24

principle of Parsimony

Back 24

the preferred explanation is the simplest, or minimizes the number of evolutionary changes that need to be made.

Front 25

Monophyletic group

Back 25

a taxon which contains all descendants of a common ancestor

Front 26

Polyphyletic group

Back 26

a group that does not include a common ancestor

Front 27

Paraphyletic group

Back 27

a group that does not include all descendants of a common ancestor.

Front 28

Morphological species concept

Back 28

species are IDed by differences in their morphological (physical) traits

Front 29

Biological species concept

Back 29

groups of actually or potentially interbreeding populations that are reproductively isolated from other populations

Front 30

Phylogenetic species concept

Back 30

analysis of molecular sequence of DNA determines that organisms are sufficiently different to be considered separate species.

Front 31

Ecological species concept

Back 31

organisms are considered separate species if they occupy separate ecological niches

Front 32

Reproductive isolation

Back 32

there is some type of barrier to producing fertile, viable offspring

Front 33

Prezygotic barrier

Back 33

prevent fertilization of the egg

Front 34

Postzygotic barrier

Back 34

prevent zygote from developing into a fertile adult

Front 35

Habitat Isolation

Back 35

2 organisms occupy different habitats and encounter each other rarely.
-impedes mating

Front 36

Temporal Isolation

Back 36

Differences in time of mating season impedes mating.

Front 37

Behavioral Isolation

Back 37

Failure to recognize other species as a potential mating partner due to behavioral differences.

Front 38

Mechanical Isolation

Back 38

Differences in size and shapes of reproductive organs impedes mating

Front 39

Gametic Isolation

Back 39

Sperm of 1 species cannot attach to and/or fertilize eggs of another species.

Front 40

Reduced Hybrid Zygote Viability

Back 40

Zygote fails to mature

Front 41

Reduced Hybrid Fertility

Back 41

Hybrid offspring are infertile

Front 42

Reduced Hybrid Adult Viability

Back 42

Offspring of hybrids are less fit, have many deleterious recessive alleles.

Front 43

Anagenesis

Back 43

change in gene frequencies that alter a species over time

Front 44

Cladogenesis

Back 44

Splitting the gene pool into separate pools that give rise to one or more new species.

Front 45

Allopatric Speciation

Back 45

organisms become divided by a physical barrier.

Front 46

Sympatric speciation

Back 46

No physical barrier. Often the result of disruptive selection