Evo Bio Test1 Part 2

Front 1

What type of selection is clutch size in birds and why?

Back 1

It is stabilizing selection because the average number of eggs produced to favor the bird's clutch size.

After selection, the average number of eggs laid will stabilize to the optimal number of young that the parent can provide enough food/resources for with the average clutch size.

Front 2

disruptive selection:

Back 2

When phenotype intermediates are selected against and a bimodal distribution phenotype value is produced. It INCREASES phenotypic variation in a population

Front 3

What type of selection relates to phenotypic fur color?

Back 3

Disruptive selection. Occurs when mice end up clonizing in two different enviornments that require different colors of camouflage in order to avoid preation. It increases phenoytypic varation.

Front 4

What type of selection relates to the mimaism moth?

Back 4

Disruptive selection-- the low polution areas have lighter moths to blend into the trees and the high pollution areas have darker moths to blend in to the polluted darker trees.

Front 5

Frequency dependent selection

Back 5

The fitness of a phenotype depends on its frequency in the population. Usually occurs if there is selective pressure against a host by a particular pathogen. If pathogens are more adapted to a particular genotype-- than that genotype is slected against, and the rare genotype will have the advantage.

Population mean value will oscillate to keep population mean fitness stable.

Front 6

Why are oscillations in genotypes of a frequency-depenant selection required to
stabilize population mean fitness at its maximum level?

Back 6

sfgh

Front 7

What type of selection increases phenotypic variation among a population?

Back 7

disruptive selection. This occurs often in patchy environments, when mice average colors or something provides no benefit to camouflage. It can even result in speciation if the two different environments are so different that the mice will stop interacting.

Front 8

What type of selection is the African fish that attack the sides of other fish?

Back 8

Frequency depenetn selection. Because the fish that does not attack the same side of the other fish... will be able to sneak attack on the prey's learned defensive response.

Front 9

the _______ of ineffectively traits of the ______ will change in response to the rare genotypes having an ____ and will push the ______ into a _____ pattern.

Back 9

requency of
infectivity traits of the
pathogen will change
in response to the rare geneotypes having an advnatage, _pushing
the hosts into
oscillating pattern

Front 10

canalizing selection

Back 10

important traits are stablizied by mulitple factors in the genome so population mean value will stay the same with almost no variation.

Front 11

Why do genotypes that have more or less kidneys than 2 have have a large coefficient of selection against them?

Back 11

Due to the canalizing selection theory-- that the optimal number of kdiness is so important that kidneys have evolved to be resistant to change. Also the theory predicts that there might be variation in the mechanisms but there were be other mechanisms to mitigate the physical effects of that variation-- so any new variation will remain hidden from selection.

Front 12

3 hypothesis of hamilton and zuk

Back 12

1. Parasites reduce host fitness
2. no coevolution between hosts and parasites, and hosts evolve genetic resistance to their parasites
3. the hosts with higher resistance are in general better health and have stronger sexual displays

Front 13

Examples of Selection that can cause speciation and Why?

Back 13

1. Runaway selection
Innate female fondness for the same traits as the brother, decreases genetic diversity?
2. Disruptive selection
If the 2 habitats of the same species are so different and cause phenotypic variation that prevents the one phenoytype from moving to other habitats to mate with the other phenoytpe;

Front 14

What is migration implicitly recognized as?
On an _______ level, ________ engage in a type of locomotory activity that is "______,"_______ and ____ __"

Back 14

An adaptation.Migration is based on transitory availability and location of resources like space, food, climate, shelter, mates.

Front 15

Can migration lead to redistribution?

Back 15

Yes- as populations, organisms may exhibit movement leading to redistribution within a spatially extended population.

Front 16

On an _______ level, ________ engage in a type of locomotory activity that is "______,"_______ and ____ __"

Back 16

On an individual level organisms engage in a type of locomotory activity that is undistracted, persistent and straighten out.

Front 17

Why do grasshoppers turn into locusts at a certain threshold?

Back 17

At first, grasshopers are solitary living in greater distances between scarce vegetation and are cryptically colored green to blend in.

There is a density dependent response of the ( vegetation of the other grasshoppers) during which the grasshopper's antenna will touch another grasshoppers leg receptor and cause a physiological change into a gregarious locust.

Front 18

What is the genetic combination of locus interaction?

Back 18

Gene Flow
migration

Front 19

What is gene flow?

Back 19

Gene flow is the transfer of alleles of genes from one population to another. Gene flow introduces new alleles to a population and makes the 2 separate populations more similar.

Front 20

The change in alele frequency due to migration within a population depends on 2 things?

Back 20

1. The proportion of immigrants
2. The Difference in allele frequencies between the 2 populations

Front 21

What is the frequency of allele A in island population after migration?

Back 21

Pm= (1-m)pi + m (pc)
(1-m)= fraction of island that is native
pi= frequency of A allele on island
m= fraction of island that is immigrants
Pc= frequency of A allele on continent

Front 22

What is the CHANGE in frequency of the A allele in island population after migration?

Back 22

Delta P= m( pc- pi)

m= fraction of island that is immigrant
Pc= frequency of A allele on continent ) the original
Pi=Frequency of A allele on island ( the new)

Front 23

When delta P is negative?

Back 23

The change in the A1 allele frequency is negative means that the relative number of A1 alleles is decreasing due to the introduction of the q alleles.

Front 24

What is the only source of new variation?

Back 24

MUTATION. it is the only source of genetic variation.
Single nuclotide polymorphism ( point mutation to the duplication of an entire genome) GENOME DUPLICATION CAN CREATE NEW SPECIES

Front 25

chromosomal inversion

Back 25

alleles inside the inversion are likely to be transmitted together. mutation

Front 26

point mutation

Back 26

causes new alleles

Front 27

What has the highest and lowest rates of mutations?

Back 27

highest 10^2= viroids
lowest 10^-11= higher eukaryotes

The more complicated you are the least amount of mutations you have

Front 28

how do selection and mutation relate?

Back 28

Selection acts to eliminate deleterious mutations from populations. While mtuation creates genetic variation over time, because most of the mutations are neutral and even non- neutral mutations are deleterious-- unlesss they are peristed over time .

Front 29

How can harmful recessive alleles be maintained in the population?

Back 29

mutation rate and selection against the mutation are in equilibrium of q hat.

Front 30

What is the selection coefficient agianst the gene for cystic fibrosis

Back 30

the selecitve fitness is 1- YOU WILL DIE

Front 31

If the calculated mu or mutation rate is significantly lower than it should be to maintain the mutation selection balance..

Back 31

Then something else must be keeping q in the population-- the heterozygote advantage.

CF hetrozygotes are resistant to CTFr typohoid fever somehow.

Front 32

q hat for mutation-selection balance=

Back 32

square root of ( u/s)

u= mutation rate
s= selection coefficient

Front 33

R A fisher and his contribution to evolutionay synthesis

Back 33

In general populations are "large" and slection is efficient

Front 34

sewall wrigtht and his contribution to evolutionary synthesis

Back 34

-Populations may be “subdivided”, and
drift may reduce the efficiency of selection
- populations occurred in small isolated units: reduces efficiency of selection

Front 35

genetic drift

Back 35

Chance events can come to dominate the allele frequency in small populations

Front 36

what needs to happen for genetic drift to occur

Back 36

there must be a small population
allele frequencies have to change on the basis of chance alone
and if there are no other evolutionary forces then genetic drift can result in gene fixation

Front 37

Founder effect:

Back 37

loss of genetic variation when a small population is made from a small.

This is an exampe of genetric drift

Front 38

genetic drift in humans example

Back 38

autism-
founder effect:

d. Humans: porphyria is a genetic disorder that disrupts haem metabolism. Found in population in Afrikaan- speaking south Africans ( 1/300)
i. A C-T transition in the protoprophyinogen PPo geneThe allele is not in British
ii. Studies have suggested that most carriers in South Africa descend from a single couple from the Netherlands who married in Cape Town in 1688

Front 39

What happens in large populations and genetic drift

verus small populations

Back 39

genetic drift can affect the trajetory of allele frequency chagne but not the eventual fate of the allele.

In small populationsdrift is more powerful than selection and drives evolution to fix alleles that are not favored by selection Fishecer did not except this.

Front 40

b. Snake: Natrix tesellata

Back 40

example of founder effects in animals:

endangered snake that occurs in natural and introduced populations
c. Two natural and two introduced populations were studied for genetic variation using 8 microsatellite loci

Front 41

What is the probability of an alleles fixation in genetic drift?

Back 41

the probability of the fixation of an allele is equal to its initial frequency only if the population is SMALL and genetic drift is the ONLY evolutionary froce

Front 42

How does flipping a coin show how chance events can dominate the allele frequency in small populations?

Back 42

The more tosses you have, the deviations become less and less likely, but the probability of it being 50% heads/ 50% hands, the more likely occur
• Example: if you only do 1 trial the probability of have 50% heads is 1

Front 43

Dobhanzky fly experiment

Back 43

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Front 44

Genetic drift v flow

Back 44

Flow: the spreading of alleles across space
Movement of genetic variation in space across populations
Drift: only can occur in small populations! Allele fixation is due to a poor sample size

Front 45

Wallace vs. Darwin

Back 45

Never agreed on the role of “sexual selection”
Wallace only believed in natural selection
Darwin beleieves that sexual selection is not due to survival but about reproduction.
These traits that increase mating success, if heritable, will cause natural selection.

Front 46

parental investment

Back 46

the energy and time expended in constructing an offspring and caring for it.
-increase the reproductive success of the offspring
Decrease the reproductive success that the investing parent may achieve in the future through additional offspring

In general : females invest more in offspring than males, the eggs are large full of nutrients an expensive to produce. So females a more maternally invested in offspring than males who only donate dna sperm

Front 47

What are the limits of female and male reproduction?

Back 47

Female reproductive success is limited by the number of eggs, the energy investment but not by partners

Male reproductive success is Limited by number of females he can convenience to mate with him
Limited by competition.
Male fitness determined by access- so the major dynamic among males is
competition

The mate with a greater parental investment an be more cchoosey.

Front 48

3 main ways of male competition

Back 48

1. direct combat: access to mating
2. sperm competition: access to eggs
3. Infanticide: removal of other males offspirngs

Front 49

The male iguana is bigger because...

Back 49

of sexual selection of direct combat larger indivudals are better at head bobbing which is good for
1. visual display
2. holding larger territories ( which result in more copulation and more reproductive success)

Front 50

Visual display of male direct combat example

Back 50

i. The female red-winged blackbird are attracted to red eppletes and aerial displays and their songs
ii. Experiment: in 7 control birds, they maintained territory, but the ones that lost their red color due to painting did not maintain territory

Front 51

example of sperm competition in rodents

Back 51

relative size of the testes were proportional to the amount of offspring that were sired.

Front 52

Sperm competition among fruit flies

Back 52

ii. Fruit flys: when raised in the prescence of other males- they will produce more sperm than when raised in isolation

Front 53

Mating plugs/anti-aphrodisiacs/sperm scoops

Back 53

sperm competition:


i. Sperm plugs:
ii. Butterfly Antiaphrodisiacs in Heliconius
iii. Males produce chemicals that they transfer to females during copulation
iv. The active chemical ((E)-β-Ocimene) makes females unattractive to subsequent males
v. These males interrupt mating before sperm transfer
plugs: bettles have spines on penis that use to remove the sperm from other males

Front 54

Mate gaurding example

Back 54

In many species, such as the Seychelles warbler, female birds seek extra-pair copulations.
Males guard females during most fertile period, until female lays an egg.
Study compared 20 pairs in which there were normal levels of mate guarding with 20 pairs in which mate guarding was reduced by placing a fake model egg in the nest
Control males spent 53% of their time near their mates. Experimental males spent 8% of their time near their mates.

Front 55

Infanticide

Back 55

a. Important and different: highlights the nature of evolutionary fitness .
i. Be better in terms of reproduction
ii. Or make everyone else BAD
b. Lion, males take over prides let by other males then kill nursing cubs.
c. Direct positive fitness advantage by reducing the success of the other male.
d. This results in a faster return to breeding condition of females

Front 56

detrimental

Back 56

deleterious

Front 57

When does W bar go to 1?

Back 57

under directional selection- the alleles will be displayed in a way to maximiaze evolutionary fitness

Front 58

Q hat=

Back 58

The value when allele frequencies stop changing when the population is at MAX fitness or when the w bar is zero. If q hat is not equal to the q we have no we are not at mix fitness.

Q hat you're at w max

Front 59

delta q=0

Back 59

delta q = q1-q0
delta q is how we can predict the q in the next generation.

occurs the maximum amount of fitness.

Front 60

Selection coefficient

Back 60

s=1-W

A huge S means heterozygote disadvantage