EXAM FOCUS

Question 1

What is the criteria for selection to act and population to evolve

Answer 1

Genetic/phenotypic variance

Heritable

Non-random fitness advantage

Question 2

what did peter and rosemary grant determine about the medium ground finch

Answer 2

the beak sizes influences the efficiency of eating different types of seeds

Question 3

what happened to beak size in droughts

Answer 3

the birds evolved larger beaks bc only harder, woody seeds are available

Question 4

what are Hermaphrodites

Answer 4

they self-ferilize and reproduce sexually but dont create genetic variation

Question 5

what is sexual female reproduction?

Answer 5

between the opposite sex

creates genetic diversity

Question 6

what is asexual female reproduction

Answer 6

between the same sex

does not contribute to genetic diversity

Question 7

what is the advantages and disadvantages of sexual reproduction

Answer 7

Advantages:
Combining beneficial mutations

generating novel genotypes

genetic diversity

Diluting harmful mutations

Disadvantages:

contribute to only 50% of gene from one parent while asexual contribute to 100%

Cost of search

Lower relatedness of offspring

risk of sexually transmitted disease

combining harmful mutation when inbreeding is high

Question 8

why is anisogamy

Answer 8

results in differential investment in reproduction such as egg and sperm size difference

Question 9

what is female limitations for reproduction?

Answer 9

• limited fecundity (limited number of offspring they can produce)

Question 10

what is the limitation for male reproduction?

Answer 10

• limited number of mates
• they have uncertain paternity

Question 11

what is operation sex ratio? (OSR)

Answer 11

ratio of males to females capable of reproducing at a given time

Question 12

what happens to the OSR when theres a slower rate of reproduction by females?

Answer 12

it leads to male biased OSR causing more males to compete for limited number of fertilized females. Intense male-male competition

Question 13

what is intrasexual selection?

Answer 13

armaments which are weapons used to outcompete other individuals

Question 14

what is intersexual selection?

Answer 14

ornaments that are attractive traits that increase mating success

Question 15

how does males maximize their fitness?

Answer 15

By mating with multiple females and maintaining their OSR

Question 16

What are examples of intersexual selection in the females perspective?

Answer 16

Sexual Dimorphism. The more colorful males are can be attractive because it indicates good health and fitness and is a dominant trait

Question 17

what happens when the ORS is male biased?

Answer 17

There will be more male-male competition causing the male mortality rate to increase

Question 18

what are direct benefits for females to select their males

Answer 18

By food, nest sites, protection, help raising young, reduced risk of mating with male in poor condition

Question 19

what are indirect benefited for females to select their males

Answer 19

the genetic quality of the offspring, alleles that have good ornaments

Question 20

what does costly ornanments can signal honesty mean?

Answer 20

it suggests that they have superior genes and have a good health to maintain their ornaments

Question 21

what are the types of mating systems?

Answer 21

monogamy
polygyny
polyandry

Question 22

what is monogamy

Answer 22

one male pairs with one female and mate with them only no cheating

Question 23

what is polygyny?

Answer 23

males mate with multiple females

Question 24

what is polyandry?

Answer 24

females mate with multiple males

Question 25

why does mating system evolve?

Answer 25

they evolve because of the benefits and costs they have on females and males

Question 26

what does polyandry benefit?

Answer 26

females select for male traits that increase paternity leading to sperm competition among males

Question 27

what is sexual conflict?

Answer 27

traits that causes a fitness benefit on one sex at a cost to the other sex. Coevolve antagonistically

Question 28

why are sex ratios balanced?

Answer 28

the production of each sex is favor when rare

Question 29

What is the drivers-willard hypothesis

Answer 29

mothers alter sex ratios depending on condition in a polygynous species females in good condition produce males females in poor condition produce females

Question 30

how can some species switch sex

Answer 30

in a particular fish, the largest female switchs to male and has monopoly on paternity

Question 31

what is genomic imprinting

Answer 31

silences gene expression by methylation by one parent

Question 32

what is mother hypothesis?

Answer 32

risk of reproduuction at older age selects for reduced fertility

Question 33

what is grandmother hypothesis?

Answer 33

loss of fertility shifts investment to grandchildren, increase in fitness

Question 34

what are ways to identify species?

Answer 34

biological species concept phylogenetic tree concept ecological species concept

Question 35

what are isolating barriers?

Answer 35

geographic and reproductive

Question 36

what are geographic isolating barriers?

Answer 36

a landscape prevents gene flow. ex a blockage - causes allopatry

Question 37

what are reproductive isolating barriers?

Answer 37

organisms that prevent interbreeding - causes sympatry

Question 38

what are premating barriers?

Answer 38

timing of reproduction

Question 39

what is gametic incompatibility?

Answer 39

sperm or pollen from one species fail to penetrate and fertilize egg

Question 40

why does hybrids have low fittness

Answer 40

it can cause hybrid inviability, hybrid sterility, ecological inviability, and behavioral sterility

Question 41

what is Bateson-dobzhansky-muller incompatibilities

Answer 41

they arise from epistatic interactions of two or more loci

Question 42

what is reinforcement

Answer 42

natural selection favors prezygotic isolation mechanism

Question 43

what is parapatric speciation?

Answer 43

partial geographical barrier that seperates populations

Question 44

what is biogeography

Answer 44

study of the distribution of species across space and time

Question 45

what is dispersal?

Answer 45

movement of populations form one region to another

Question 46

what is vicariance?

Answer 46

formation of geographic barriers to dispersal that divide a once continuous population

Question 47

what are the three evolutionary faunas

Answer 47

cambrian, paleozoic, and modern

Question 48

what is anagenesis?

Answer 48

wholesale transformation of a lineage from one form to another. an alternate lineage

Question 49

what is punctuated equilibria?

Answer 49

periods of stasis punctuated by brief periods of rapid change

Question 50

what is gradualism

Answer 50

slow, gradual morphological changes over time

Question 51

what is adaptive radiation?

Answer 51

a single ancestral species rapidly diversifies into a wide variety of forms

Question 52

what happened during the cambrian explosion?

Answer 52

the ecology of the ocean changed giving rise to new species. evolving a new genetic toolkit, novel body segmentation and body parts. O2 levels increased and new ecological interactions

Question 53

what is background extinctions?

Answer 53

the normal rate of extinction for a taxon or biota

Question 54

what is mass extinction?

Answer 54

a significant increase above background extinction rate

Question 55

what are the big five mass extinction events?

Answer 55

ordovacian-silurian, late devonian, permian, triassic-jurassic, cretaceous-tertiary

Question 56

what caused ordovacian extinction

Answer 56

ice sheets fall in sea level and changed ocean chemistry making 85% marine life extinct

Question 57

what caused the late Devonian mass extinction

Answer 57

increase of temperature changes in sea level , 75% of all species went extinct worst in shallow marine

Question 58

what caused the permian mass extinction

Answer 58

asteriod impact and eurptions from volcano caused methane to release leading to climate change, sea level flunctiations, and drop in oxygen concentrations

Question 59

what caused triassic jurassic mass extinction

Answer 59

climate change, central atlantic flood, basalt euptions, asteirod impacts. 80% of all species went extinct, most marine reptiles, large amphibians, corals and mollusks

Question 60

what caused the cretaceous tertiary mass ext

Answer 60

flood basalt euptions, climate change and decrease in sea level. finished off with a large asteriod. Extinction of Dinos and flowers

Question 61

what causes antropocene extinction

Answer 61

overharvesting, land-use, invasive species, toxicity due to pollution, climate change