Natural Selection

Question 1

What is the evidence that supports the theory of evolution.

Answer 1

The fossil record, comparative morphology, biogeography.

Question 2

What does the fossil record do

Answer 2

Gives a visual of evolutionary change over time

Question 3

what is comparative morphology

Answer 3

analysis of the structures of living and extinct organisms

Question 4

what is homology

Answer 4

characteristics in related species that have similarites even if functions differ

Question 5

Whats Embryonic homology

Answer 5

Mant species have similar embryonic development

Question 6

whats a vestigial structure

Answer 6

Structures that are conserved even though they no longer have a use ie tailbone

Question 7

Whats molecular homology

Answer 7

Many species share similar dna and amino acid sequences

Question 8

whats a homologous structure

Answer 8

Characteristics that are similar in two species because they share a common ancestor ie arm bones in many species

Question 9

whats convergent evolution

Answer 9

similar adaptations that have evolved in distantly related organisms due to similar environments

Question 10

whats a analogous structure

Answer 10

structures that are similar but have seperate evolutionary origins

Question 11

What is biogeography

Answer 11

the distribution of animals and plants geographically. Exaple species on oceanic islands resemble mainland species

Question 12

How can structures become vestigial from natural selection

Answer 12

A structure could have been useful at one time but there could have been a mutation that made it useless

Question 13

What is phylogenetics

Answer 13

the hypothesis of evolutionary history

Question 14

How do scientists determine evolutionary relationships

Answer 14

fossil records, DNA, proteins, homologous structures

Question 15

what are two clades that come from the same node

Answer 15

sister taxa

Question 16

whats a derived characteristic

Answer 16

a similarity inherited from the most recent common ancestor of an entire group

Question 17

whats a outgroup

Answer 17

a lineage that is the least closely related to the rest of the organisms

Question 18

whats the principle of parsimony

Answer 18

Use the hypothesis that requires the fewest assumptions

Question 19

what is the RNA world hypothesis

Answer 19

proposes that RNA could have been the earliest genetic material

Question 20

what is evolution

Answer 20

change in the genetic makeup of a population over time (descent with modification)

Question 21

whats natural selection

Answer 21

A process in which individuals have certain traits tend to survive and reproduce at higher rates than other individuals because of those traits

Question 22

whats an adaptation

Answer 22

inherited characteristics of organisms that enhance their survival and reproduction

Question 23

what is the theory of natural selection based on

Answer 23

Traits are heritable, more offspring are produced than can survive

Question 24

what does producing more offspring that can survive cause

Answer 24

it leads to competition for limited resources which result in differential survival

Question 25

what is artifical selection

Answer 25

the selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits

Question 26

whats a species

Answer 26

a group able to interbreed and produce viable fertile offspring

Question 27

whasts speciation

Answer 27

formation of a new species

Question 28

whats allopatric speciation

Answer 28

Physical barriers divides population or a small population is separated from the main population

Question 29

whats sympatric speciation

Answer 29

A new species evolves while inhabiting the same geographic region, usually due to exploitation of a new niche

Question 30

whats a prezygotic barrier

Answer 30

something that prevents mating or hinders fertilizatiom

Question 31

what are tje 5 types of prezygotic barriers

Answer 31

habitat isolation temporal isolation behavioral isolation mechanical isolation gametic isolation

Question 32

what is habitat isolation

Answer 32

sppecies live in different areas or they occupy different habitats within the same area

Question 33

whats temporal isolation

Answer 33

species breed at different times

Question 34

whats behavioral isolation

Answer 34

unique behavioral patterns and rituals seperate species

Question 35

whats mechanic isolation

Answer 35

the reproductive anatomy of one species does not fit with the anatomy of another species

Question 36

whats gametic isolation

Answer 36

proteins on the surface of gametes do not allow for the egg and sperm to fuse

Question 37

whats a postzygotic barrier do

Answer 37

they prevent a hybrid zygote from developing into a viable fertile adult

Question 38

what are the three types of postzygotic barriers

Answer 38

reduced hybrid viability reduced hybrid fertility hybrid breakdowm

Question 39

what is reduces hybrid viability

Answer 39

the genes of different parent species may interact in ways that impair the hybrids development or survival

Question 40

Whats reduced hybrid fertility

Answer 40

a hybrid can develop into a healthy adult but is sterile

Question 41

whats hybrid breakdown

Answer 41

the hybrid of the first generation may be fertile but when they mate with a parent species or one another their offspring will be sterile

Question 42

whats microevolution

Answer 42

change in allele frequencies withing a single species or population (natural and sexual selection, genetic drift, gene flow)

Question 43

whats macroevolution

Answer 43

large evolutionary patterns (adaptive radiation, mass extinction)

Question 44

whats stasis

Answer 44

no change over long periods of time

Question 45

whats punctuated equillibrium

Answer 45

when evolution occurs rapidly after a long period of stasis

Question 46

whats gradualism

Answer 46

when evolution occurs slowly over hundreds thousands or millions of years

Question 47

whats divergent evolution

Answer 47

groups with the same common ancestor evolve and accumulate differences resulting in the formation of a new species

Question 48

whats adaptive radiation

Answer 48

if a new habitat or niche becomes available species can diversify rapidly

Question 49

whats convergent evolution

Answer 49

two different species devlop similar traits despite having different traits analogous traits

Question 50

whats a gene pool

Answer 50

a populationsn genetic makeup all the alleles

Question 51

what is evolution driven by

Answer 51

Random occurences mutations genetic drift migration/gene flow natural selection

Question 52

whats genetic drift

Answer 52

chance events that cause a change in allele frequency from one generation to the next most significant to small populations, can lead to loss of genetic variation, can cause harmful alleles to become fixed, does not produce adaptations

Question 53

whats bottleneck effect

Answer 53

when a large population is drastically reduced by a non selective disaster

Question 54

whats founder effect

Answer 54

when a few individuals become isolated from a large population and establish a new small population with a gene pool that differs from the large population

Question 55

whats gene flow

Answer 55

transfer of alleles into or out of a population due to fertile individuals or gametes

Question 56

what measures reproductive success

Answer 56

relative fitness

Question 57

what is relative fitness

Answer 57

the number of surviving offspring that an individual produces compared to the number left by others in the population

Question 58

whats directional selection

Answer 58

selection towards one extreme phenotype

Question 59

whats stabilizing selection

Answer 59

selection towards he mean and against the extreme phenotypes

Question 60

whats disruptive selection

Answer 60

selection against the mean, dom/ rec are the best

Question 61

whats sexual selection

Answer 61

a type of natural selection that explains why species have unique/showy traits

Question 62

what are five conditions for HW equillibriun

Answer 62

no mutations random mating no natural selection extremely latge population size no gene flow