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1
Q

What is are the axes of a graph showing heritability?

A

X - midparent
y - midoffspring

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2
Q

What is epistasis?

A

Non additive meaning one or the other

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3
Q

What is pleiotropy?

A

An allele can affect multiple things

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4
Q

What is the classical school of thought on variation, how about the balance school of thought?

A

Classical - variation low and harmful
Balance - variation high and beneficial

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5
Q

What is the Wahlund effect?

A

Reduced observed heterozygosity compared to expected due to population structure (includes selection, gene flow, and genetic drift)

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6
Q

The higher the effective population size, the ____ amount of polymorphism

A

Higher

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7
Q

What is the equation of fitness, w bar?

A

MxL=wbar
M - mating success
L - survivorship

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8
Q

What is the difference between Mendelians and Biometricians?

A

Mendelians believe in no intermediates which is possible when only one loci is responsible for a trait while biometricians believe in many intermediates when several loci are responsible

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9
Q

What’s the Breeder’s Equation?

A

R = h^2 S
R - response to selection aka evolution
H^2 - heritable variation
S - selection

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10
Q

What is h^2B and what is h^2N?

A

H^2B = VG/VP = VG / VG + VE = VA + VD + VI(epistatic) / VG + VE
H^2N = VA/VP = VA / VG + VE

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11
Q

What is the slope of a heritability graph equal to?

A

H^2N

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12
Q

What are axes of a selection gradient?

A

X - trait
Y - relative fitness

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13
Q

What are the axes of a selection differential?

A

X - trait
Y - number of individuals

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14
Q

Which sweeps are hard to detect?

A

Soft sweeps and polygenic adaptation

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15
Q

Is an lineage thats existed for 200M years more likely to survive extinction?

A

Nope

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16
Q

How do hox genes relate to evolution?

A

Messing around with hox genes allows for differences in morphology

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17
Q

What is introversion?

A

Gene flow from one species to another (aka Neanderthal fucking humans)

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18
Q

What is incomplete lineage sorting?

A

The gap between the gene tree and the species tree

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19
Q

Should you do lineage sorting at one spot or many?

A

Many because at just one spot you might find NO differences

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20
Q

What is Haldane’s rule?

A

You’ll see a change in the heterogemetic sex first

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21
Q

What is morphological stasis?

A

Staying the same shape over time because it has high fitness

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22
Q

What is directional selection?

A

Selects for large or small values

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23
Q

What is stabilizing selection?

A

Selects for intermediate trait values

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24
Q

What is disruptive selection?

A

Selects for extreme trait values

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25
What is an adaptation?
A trait acted upon by natural selection to fulfill a particular function
26
What are the steps of determining if something is an adaptation?
- Measure selection - demonstrate a relationship between env and trait - demonstrate a link between trait and fitness - make sure u reject null hypothesis of drift - measure heritability - find the genes (not necessary)
27
What is isogamy?
All gametes are the same size - in some species all gametes can fuse - in others, only diff mating types can fuse
28
What is anisogamy?
Gametes are size-dimorphic - only gametes of diff sizes can fuse
29
What are the advantages of sex?
- removal of deleterious muts - creating novel phenotypes to help environmental changes
30
What is the Fisher-Muller effect?
Asexuals need a descendent with a beneficial mutation and need to develop another beneficial mutation to get two beneficial mutations. Sexual can get several mutations with different origins in a single organisms through recombination
31
What is Muller’s Ratchet?
Beneficial mutations in an asexual population can be lost forever by chance. It also states that genetic load increases over time (genetic load = decrease in fitness due to deleterious mutations)
32
What affects the rate of Muller’s Ratchet in asexuals?
- Strength of drift (Ne) - Mutation rate - impact of deleterious mutations
33
What is bet-hedging?
The idea that having variable offspring increases the odds that some will survive an ever changing environment
34
How does sex benefit host-parasite coevolution?
Sex creates rare genotypes which makes it hard for parasites to target them
35
What is frequency-dependent selection?
Red queen, parasites and hosts chase each other and their frequencies go up and down
36
What are the axes on a sexual selection gradient?
Y - mating success X - trait
37
What is operational sex ratio?
Ratio of reproductively active males to females
38
Will members of sex with strong sexual selection compete for mates or be choosy?
Compete for mates
39
What’s intrasexual competition?
Differential mating success due to interactions within their sex (aka males fighting for dominance)
40
What is intersexual selection?
Differential mating success due to interactions with members of the other sex (males trying to impress females)
41
What do external fertilizers favor?
MORE sperm
42
What to internal fertilizers favor?
Faster sperm
43
What are the four reasons for choosing sexual selection?
1. Nothing, arbitrary 2. Pre-existing sensory bias 3. Direct benefits 4. Indirect benefits
44
What does inclusive fitness include (lol)?
Direct + Indirect fitness
45
What is Hamilton’s Rule?
Br - C > 0 B - benefit to the recipient R - relatedness to actor and recipient C - cost to actor
46
What is multilevel selection?
Cooperation with organisms that are NOT related, if the cooperation helps their group then cooperation will increase in frequency in the population, even if it doesnt increase within groups
47
How do you calculate genetic load?
1 - wbar = Load
48
What is neutral theory?
Most changes must be neutral therefore the main driver of evolution is genetic drift
49
What areas of the genome evolve slowest?
Those near histones
50
What areas of the genome evolve the fastest?
Introns
51
How does neutral theory explain variation in populations?
You’re simply seeing mutations on their way to fixation or loss, NOT because of balancing selection
52
What does nearly neutral theory state?
- as Ne goes down, more mutations will be effectively neutral - as Ne goes up, selection is the main driver - predicts high heterozygosity in big pops - predicts an inconstant molecular clock
53
What should low levels of evolution reflect in dN/dS ratios?
N should be low, S should be high
54
Are hard sweeps consistent w/ neutrality?
No
55
If there is a molecular clock, what should the relative rates equations look like?
Ya-yb=ao-bo
56
What are McDonald Kreitman tests?
N/S ratios with Polymorphism/Dimorphism, both P and D should be equal under neutrality
57
What does being diploid allow for?
Redundancy, have a back up set
58
As genome size increases in non eukaryotes, mutation rate ___
Decreases
59
As genome size increase in eukaryotes, mutation rate ____
Increases
60
As Ne increases, what happens to mutations per coding DNA per generation?
Decreases
61
What are the two possible reasons organisms age and die?
Mutation accumulation and antagonistic pleiotropy
62
What is the mutation accumulation hypothesis?
- late acting deleterious mutations are weakly selected against - the later in life a mutation has an affect, the weaker its select against
63
What is the antagonistic pleiotropy hypothesis?
Alleles that have an early benefit but a late cost can be adaptation
64
What is extrinsic mortality?
Age specific risk of death
65
What does high extrinsic mortality favor?
Early reproduction and weak selection on aging
66
What does low extrinsic mortality favor?
Later reproduction and slower aging
67
What is genomic imprinting?
Biochemical marks that distinguish paternal and maternal alleles (like mouse IGF-II)
68
What is the coincidental evolution hypothesis?
Pathogen virulence is not a target of selection itself
69
What is the shortsighted evolution hypothesis?
Traits that enhance pathogen fitness within hosts decreases transmission between hosts (cus it kills the host)
70
What is the trade off hypothesis?
Virulence can be favored by selection is killing the host increases its chance of being transmitted
71
Describes the axes of red queen (frequency dependent)
X - generation Y - genotype freq Two curves that have slightly different periods for the host and parasite, parasite usually ahead
72
Describe the axes of arms race
X - generation Y - frequency Two S curves that reach 1.0 and then start another pair of S’s
73
What are the axes of a time shift experiment and which would prove red queen and which would prove arms race?
X - host time point Y - parasite infectivity Red queen - progressive rise then shoots down Arms race - progressive decrease from high infectivity
74
What kind of selection is red queen?
Balancing
75
What kind of selection is arms race?
Positive (many selective sweeps)
76
What are the prezygotic barriers?
- habitat - temporal - behavioral - mechanical - gametic
77
What are the postzygotic barriers?
- reduced hybrid viability - reduced hybrid fertility - hybrid breakdown
78
What does allopathic mean?
Species is separated into two groups by a barrier
79
What is reinforcement?
Not mating with hybrids, furthering isolation
80
What does parapatric mean?
Two areas separated by a border
81
What does peripatric mean?
- small isolated populations - bottleneck - NEW environments
82
What is sympatric?
NO boundaries
83
What is Haldane’s Rule?
When F1 offspring of two diff animal races one sex is absent, rare, or sterile, that sex is the heterozygous one
84
Sympatry had ___ rates of speciation
Increased
85
As genes become more different, they become more ___
Isolated
86
Selection favors lineages with ____ ____ __ ______
Increased rates of origination
87
What is Cope’s Rule?
Body size in species tens to increase over evo time
88
What is biogenetic law?
Ontogeny recapitulates phylogeny
89
What is allometry?
Diff body parts evolving at diff rates
90
What is heterochrony?
Developmental programs being done at diff times of development
91
What are hox genes?
HIGHLY pleiotropic genes,code for major segments of the body
92
What is incomplete lineage sorting?
The gap between the gene tree and the species tree
93
Why is lineage sorting in terms of one gene a bad idea?
There are some spaces where there is no difference
94
What is the most supported theory for the evolution of Homo sapiens?
Hybridization and assimilation
95
What is polygenic adaptation?
Adapting through many small gene changes that are beneficial

Evolution (4 decks)

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