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BIO120 > 7, 8, 9, 10, 11, 12 > Flashcards

7, 8, 9, 10, 11, 12 Flashcards

1
Q

3 types of selection

A

positive (directional) selection
negative (purifying) selection
selection to maintain variation (balancing selection)

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2
Q

describe the distribution of polygenic traits

A
  • continuous distribution
  • typical of size/number traits
  • example of quantitative inheritance
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3
Q

draw and describe 3 different modes of selection on quantitative traits

A

stabilising selection favours average traits
directional selection favours one extreme
disruptive selection favours both extremes

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3
Q

what may be the effects of disruptive selection?

A
  • trait divergence
  • speciation, if trait divergence causes a reduction in gene flow
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4
Q

how can we study adaptation?

A
  • test for correlation of alleles or traits with environment over space and time and analyse genomic diversity (genes targeted by selection ought to show distinctive patterns)
  • experimental manipulations in field/lab
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5
Q

describe the struggle to determine the agents of selection

A
  • research through today shows thousands of measurements of selection
  • demonstrates fitness differences & evolutionary change in traits
    and yet:
  • many fewer convincing cases document the mechanisms (agents) of selection in natural populations
  • linking evolution to ecology is difficult
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6
Q

describe the peppered moth (biston betularia) and industrial melanism

A
  • light and dark forms of species that rest on trees
  • in the UK, before 1850, dark moths were rare
  • dark form caused by a single dominant allele of Cortex gene
  • industrial pollution blackened tree trunks near cities and resulted in an increase in the dark form
  • dark variant replaced light form in polluted areas, light form predominated in rural unpolluted areas
  • mechanism of selection due to predation by birds
  • differences in moth crypsis (camouflage) depend on trunk coloration
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7
Q

what happened to the darker melanic variant of the peppered moth after the introduction of the UK ‘clean air act’ in 1956?

A

there was a decline,

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8
Q

what does the lag in evolutionary response to changes in air pollution levels reflect for peppered moths?

A

the time required for forests to return to a more natural (unpolluted) state as well as a low initial frequency of the recessive allele for a typical coloration

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9
Q

describe the evolution of heavy metal tolerance in plants

A
  • mine waste is heavily polluted with heavy chemicals such as lead, copper, nickel, cadmium
  • heavy metal tolerant genotypes can occur at very low frequency in nearby uncontaminated pastures
  • tolerant genotypes invade mine tailings from nearby pastures
  • gene flow between pasture and mine is restricted because of flowering time differences between them
  • alleles enabling tolerance maintained on mines but not pastures
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10
Q

define a selective sweep

A

when selection causes a new mutation to increase in frequency so quickly that nearby alleles ‘hitchhike’ and also increase in frequency

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11
Q

describe DNA Variation at glucose-6-phosphate dehydrogenase deficiency in humans

A

recent natural selection has caused
- low diversity
- high frequency of derived (new) allele
- G6PD gene shows evidence of the recent, rapid spread of resistance allele (consistent with hypothesis of selection for malaria resistance)

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12
Q

describe the long term experimental evolution study of adaptation by E.Coli

A
  • 36 years if propagating 12 population flasks
  • > 75000 generations of evolution
  • propagated in minimal glucose/citrate medium
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13
Q

results of long term experimental evolution study of adaptation by E.Coli

A
  • all populations rapidly increased in fitness
  • similar adaptations across populations (eg larger cell sizes, higher max growth rates on glucose)
  • parallel mutations in same genes
  • some unique adaptations and distinct genetic changes
  • only one strain evolved ability to grow on citrate
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14
Q

define a population

A

a group of individuals of a single species occupying a given area at the same time

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15
Q

define migration

A

the movement of individuals from one population to another

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16
Q

define gene flow

A

the movement of alleles from one population to another

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17
Q

how can we measure gene flow?

A

use experimental approaches
use neutral genetic markers:
- polymorphic genetic variants that aren’t direct targets of selection

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18
Q

experiment to answer the question: how much gene flow occurs between geographically separated populations?

A
  • establish two populations, fixed for alternative alleles, separated by a given distance
  • score FS heterozygotes in offspring
  • frequency of heterozygotes = an estimate of gene flow
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19
Q

formally define genetic drift

A

stochastic changes in allele frequency due to random variation in fecundity and mortality

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20
Q

what does random mean in evolution?

A

stochastic (unpredictable or random) evolutionary forces:
- mutation
- recombination
- genetic drift

deterministic (predictable or non-random) evolutionary forces:
- natural selection

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21
Q

define population bottlenecks

A
  • a single sharp reduction in abundance, usually followed by a rebound
  • causes a loss of diversity
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22
Q

define a founder event

A
  • colonisation by a few individuals that start a new population
  • colonising group contains only limited diversity compared to the source population
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23
Q

why is genetic drift more pronounced in small populations?

A
  • more drastic fluctuations in each generation
  • more rapid loss of genetic diversity (i.e. faster time to allele fixation or loss)
  • less consistency across replicate populations
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24
Q

as distance increases, gene flow

A

decreases

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25
Q

define isolation by distance

A

accumulation of local genetic variation due to geographically limited dispersal

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26
Q

phenotypic variation may be:

A
  • adaptive (‘local adaptation’
  • due to genetic drift
  • phenotypic plasticity
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27
Q

how do we test for local adaptation and plasticity?

A

reciprocal transplant studies
Genomic analyses

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28
Q

define phenotypic plasticity

A

the ability of a genotype to modify its phenotype in response to a particular environment

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29
Q

draw 3 graphs for no plasticity, plasticity, and highly variable plasticity

A
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30
Q

how does phenotypic plasticity occur?

A

through modifications to development, growth, and/or behaviours under genetic control

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31
Q

in what organisms is phenotypic plasticity common?

A

in sedentary organisms like plants and corals, but also in animal behaviour

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32
Q

phenotypic plasticity often is an adaptation to…

A

unpredictable environments

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33
Q

does all phenotypic plasticity result from adaptation?

A

no

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34
Q

describe reciprocal transplant studies

A

Growth of equivalent genotypes in contrasting environments and comparisons of their relative
performance

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35
Q

why are reciprocal transplant studies useful?

A
  • Can separate phenotypic variation into genetic and environmental components
  • Enables measurement of selection against non‐local genotypes
  • Can provide evidence for/against local adaptation
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36
Q

Clausen‐Keck‐Hiesey Transplant Conclusions

A
  • Differences between populations due to BOTH plasticity and genetics
  • Evidence for widespread local adaptation
    – Local populations had highest fitness
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37
Q

How do we test for plasticity and adaptation in species that we can’t manipulate experimentally?

A

genomic studies

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38
Q

Tradeoffs Associated With Skin Pigmentation

A

High UV radiation:
– Degrades folate, critical in highly dividing tissues (e.g. embryos, testes)
– May have selected for increased pigmentation
- Strong purifying selection on MC1R in equatorial
regions

Low UV radiation:
– Reduced vitamin D synthesis
- VitD critical for bone development, immunity, etc.
– May have selected for reduced pigmentation

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39
Q

was there a history of local adaptation in skin pigmentation?

A

Numerous genes known to affect skin pigmentation
* These genes show higher between‐population differentiation than most others
–> Evidence supporting a history of local adaptation
* Pigmentation genes show evidence for positive selection in regions with distinctive skin
colouration

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40
Q

what was the confusion about the link between micro and macroevolution?

A

can processes of microevolution lead to macroevolution?

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41
Q

taxonomic (morphological) species concept

A

based primarily on distinct measurable differences

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42
Q

biological species concept

A

based on inter-fertility among individuals

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43
Q

why is it so hard to define a species?

A

concepts vary among groups of organisms and among scientists. There is no universal species concept.
- geographic isolation alone is NOT sufficient
- isolation does NOT have to be absolute (what cutoff?)

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44
Q

Darwin’s definition of a species

A

groups of organisms that are sufficiently similar in phenotype

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45
Q

Ernst Meyer’s view on distinguishing species

A

reproductive isolation as key to distinguishing species

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46
Q

what species does the BSC not apply to?

A

does not apply well for bacteria, asexuals, highly self-fertilising species…or fossils

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47
Q

allopatric speciation

A

often called geographic speciation
- due to involvement of geographical isolation
- much more common and easier to evolve

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48
Q

stages where reproductive isolation can occur

A

pre-zygotic:
- finding a compatible mate and mating
- fertilisation
post-zygotic:
- development and growth of zygote (F1)
- adult survival & reproduction
- growth, survival, reproduction of offspring (F2)

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49
Q

pre-zygotic barriers

A

prevent mating or fertilisation so no zygote is formed:
- geographical, ecological
- temporal, behavioural (mate recognition)
- mechanical (genital stricture compatibility)
- cellular (sperm-egg compatibility)

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50
Q

use Rhagoletis pomonella (Apple Maggot Flies) as an example of pre-zygotic isolation

A
  • host shift after arrival of domesticated applies in 1800s
  • differences in timing of host planting fruiting (apple vs hawthorn)
  • different timing of fly mating on preferred host plant)
  • reduces fly gene flow by 94% in sympatry (same region)
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51
Q

describe pre-zygotic isolation in abalone

A

binding of sperm lysin protein to egg vitelline envelope receptor (VERL) required for fertilization (molecular lock and key)
Lysin/VERL interaction has coevolved
– Different evolutionary changes in different species
– Causes reproductive isolation due to fertilization
incompatibility

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52
Q

post-zygotic barriers

A

prevent proper functioning of zygotes
once they are formed
* Caused by combinations of genes with low fitness in the
hybrid
* Arise as an indirect byproduct of evolution acting
separately in different populations (cannot be directly
favored by natural selection)

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53
Q

intrinsic post-zygotic barriers vs extrinsic post-zygotic barriers

A

Intrinsic Post‐zygotic Barriers:
* Inviability, sterility, or abnormal development of hybrids
Extrinsic Post‐zygotic Barriers:
* Ecological mismatch of hybrid phenotype to environment

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54
Q

example of intrinsic post-zygotic isolation

A

Mule is a sterile hybrid cross of:
* Male donkey (62 chromosomes)
* Female horse (64 chromosomes)

Hinny is a sterile hybrid of:
* Male horse (64 chromosomes)
* Female donkey (62 chromosomes)

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55
Q

relation between genetic distance and post-zygotic isolation in fruit flies

A
  • The more that fly pairs are genetically differentiated,
    the more likely they are to be reproductively isolated
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56
Q

example of extrinsic post-zygotic isolation

A

aposematic helicons butterflies
Hybrids have aberrant colour patterns
* Higher predation risk
* Lower mating success

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57
Q

local adaptation by different populations can lead to

A

reproductive isolation and speciation

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58
Q

distinct evolutionary responses happen due to

A

different selective pressures

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59
Q

is local adaptation necessary for speciation?

A

Local adaptation not absolutely necessary, but accelerates population divergence and
evolution of RI

60
Q

describe sticklebacks in marine and freshwater environments

A

In marine environment:
– Bony armor protects against large fish predation
In freshwater:
– Loss of armor increases growth rate
– Greater winter survival
– Earlier breeding

61
Q

so, can microevolution lead to macroevolution?

A

yes - as populations diverge genetically as a result of evolutionary forces
(mutation, natural selection, genetic drift), they become reproductively
isolate

62
Q

define and describe adaptive radiation

A

The evolution of ecological and phenotypic diversity within a rapidly multiplying lineage
– Originates from a single common ancestor
– The process results in an array of many species
– The species differ in traits allowing exploitation of a range of habitats and resources

63
Q

Four features commonly identify an adaptive radiation

A

1) Recent common ancestry from a single species
2) Phenotype‐environment correlation
3) Trait utility
4) Rapid speciation

64
Q

define ecological opportunity

A

the absence (or reduction) of competition for resources

65
Q

two things that cause adaptive radiation

A

ecological opportunity and high propensity for speciation

66
Q

how does ecological opportunity come about?

A

Colonization of competition‐free regions (e.g., islands, lakes, or continents)
Extinction (which can eliminate competitors)
Key innovation (evolution of a trait that provides access to new resources)

67
Q

high propensity for speciation

A

RI evolves more readily in some clades than others

68
Q

define hybridisation

A

The exchange of genes between species as a result of occasional inter‐species mating
– Sometimes can reverse speciation process to merge two groups into one

69
Q

how does hybridisation vary across the tree of life?

A

common in plants and fish, rare in mammals

70
Q

how can hybridisation result in complex patterns of variation?

A

Can be evolutionarily significant for speciation, especially by polyploidy

71
Q

define polyploidy

A

Describes an organism, tissue, or cell with more than
two complete sets of homologous chromosomes

72
Q

define and describe allopolyploidy

A

Allopolyploidy (e.g. AA x AA -> AA AA)
– Arises from duplicated karyotype following
hybridization between species
– Commonest type of polyploidy

73
Q

define and describe autopolyploidy

A

Autopolyploidy (e.g. AA -> AA AA)
– Arises from duplicated karyotype within a species
(e.g. non‐disjunction)

74
Q

describe how allopolyploid hybridisation comes about

A
  1. Two species mate and produce an F1 hybrid
    offspring (genotype AA*)
  2. F1 hybrid offspring produces unreduced diploid
    gametes (genotype AA*) due to meiotic
    nondisjunction
  3. Diploid gametes combine to produce tetraploid
    F2 offspring
  4. Tetraploid is fertile, but is reproductively
    isolated from parental species
75
Q

evolutionary significance of polyploidy

A

Polyploids are reproductively isolated from their
diploid parents
– Hence a form of sympatric speciation
* Polyploids exhibit novel phenotypes
– Allows exploitation of new habitats
* Polyploids often show hybrid vigor due to
heterozygosity, particularly in allopolyploids
* Polyploid origin for ~50% of flowering plants
– Many crop plants & invasive species

76
Q

draw the speciation continuum

A
77
Q
A
78
Q

Define taxonomy

A

the theory and practice of classification and naming

79
Q

define systematics

A

the study of biodiversity and the evolutionary relationships among organisms

80
Q

Carolus Linnaeus

A

1707-1778
- father of taxonomy
- binomial nomenclature
- hierarchical system of classification

81
Q

define a taxon

A

a single named taxonomic unit at any level (plural = taxa)

82
Q

7 taxa

A

kingdom (kingdoms)
phylum (phyla)
class (classes)
order (orders)
family (families)
genus (genera)
species (species)

83
Q

what is the purpose of a biological classification?

A
  • a name is key to shared information on an organism (eg scientific literature, field guides)
  • therefore has predictive power
  • enables interpretation of origins and evolutionary history
84
Q

systematics research requires

A

a robust and stable system for classifying organisms (i.e. taxonomy)

85
Q

describe how phylogenies arise/what they are made up of

A
  1. individual organisms within a population
  2. parents produce offspring
  3. lines of descent persist across generations
  4. a population is an aggregation of the genetic lineages of the individuals they contain
  5. a species is made of many populations, linked by gene flow
  6. individual species split to give rise to multiple species
  7. a phylogeny shows the relationships and evolutionary histories of species
86
Q

node

A

corresponds to historical lineage splitting events, when one lineage splits into two

87
Q

branches/ edges

A

correspond to single ancestor-descendant lineages. All branches are connected by nodes

88
Q

tips/leaves/terminals/OTUs

A

tips do not have represented descendants. can be individuals, species, clades

89
Q

internal vs external branches

A

external branches (aka terminal branches) connect a tip and a node. internal branches connect two nodes

90
Q

root

A
  • a node representing earliest time point in the diagram
  • often represented by an unlabelled branch
91
Q

sister groups/taxa

A

those that are immediate descendants of the same ancestor, eg sister species, sister branches, sister clades

92
Q

parents and daughters

A

parent branches give rise to daughter branches

93
Q

ingroup

A

consists of the focal species in a phylogenetic study

94
Q

outgroup

A

a more distant relative of the in-group taxa; can help to root the phylogeny and determine what character states are ancestral

95
Q

MRCA

A

most recent common ancestor; the youngest node that is ancestral to all lineages in a given group of taxa

96
Q

clade

A
  • any piece of a phylogeny that includes a MRCA and all of its descendants
  • i.e. any piece of a phylogeny that exhibits monophyly
97
Q

monophyly

A
  • describes a group made up of an ancestor and all its descendants
  • ie a monophyletic group or clade
98
Q

paraphyly

A
  • describes a group made up of an ancestor and some (but not all) of its descendants
  • ie a paraphyletic group or grade
99
Q

polyphyly

A
  • describes a group that does not contain the most recent common ancestor of all members
  • ie. a polyphyletic group
100
Q

for the species in a clade a trait is ancestral if

A

it was inherited in its present form from the MRCA of the clade

101
Q

for the species in a clade, a trait is derived if

A

it originated within the clade, ie in a descendant of the clade’s MRCA

102
Q

relationship between ancestral and derived clades

A

the same trait can be ancestral for a clade, but derived within a larger clade

103
Q

define a synapomorphy

A

a shared, derived trait for a clade. it is a trait that all species in the clade share, and that evolved on the branch leading to the clade (ie its derived within the context of more inclusive clades)

104
Q

homology

A

when structures observed in different taxa can be traced to a single structure present in a shared evolutionary ancestor

105
Q

homoplasy

A

when a character or character state arises more than once on a phylogenetic tree (convergence is one kind)

106
Q

why conduct a phylogenetic analysis?

A
  • understand history of life
  • understand large scale patterns of evolution
  • understand how many times traits have evolved how fast, under what conditions
  • practical: where/when did parasites spread? which fly strain is most successful? what are the driver mutations as covid evolves?
107
Q

why is phylogenetic relatedness inferred from homologous traits and not homoplasy?

A

homoplasy (eg convergent trait evolution) can mislead phylogenetic inference

108
Q

2 principal sources of macroevolutionary insights?

A

palaeontology
- provides a direct record of past evolutionary change
- inference is strongest for groups that fossilise well
phylogenetics
- provides an indirect record of past evolutionary change
- inference is strongest for groups that have living representatives

109
Q

mass extinction

A

extinction of >75% of earth’s species in a geologically short period

110
Q

uses of fossil record

A
  • provides only evidence for completely extinct clades
  • documents long-term patterns of biodiversity
  • provides evidence for catastrophic extinctions during earth’s history
111
Q

diversification rate

A

speciation rate minus extinction rate

112
Q

what happens after mass extinctions and how do we know?

A

explosive diversification; phylogenetic provides evidence for this

113
Q

features associated with increased diversification

A
  • herbivory
  • species with more sexual selection
  • animal pollination in plants
  • increased dispersal
  • increased range size
114
Q

give a broad description of the tree of life

A
  • has both simple and complex organisms
  • bacteria, archaea, and eukaryotes are main 3 groups
  • eukaryotes typically more complex in cell number, tissue types, physiology…
115
Q

major transitions in evolution

A
  • origin of cells
  • origin of chromosomes
  • origin of genetic code
  • origin of eukaryotes
  • origin of sexual reproduction
  • origin of multicellularity
  • origin of colonies (eg non-productive castes)
116
Q

what is the ultimate target of selection and why?

A

genes because they are the unit of inheritance

117
Q

what are the units competing?

A
  • DNA/gene
  • cells
  • individual organisms
  • species
  • larger clades
118
Q

why does multi-level selection pose a problem for complexity

A
  • selection at a given level of organisation means that units compete to maximise fitness
  • competition among lower-level units of organisation may reduce fitness at higher levels
119
Q

what is the solution to the multi-level selection problem?

A

if lower-level units of organisation cooperate rather than competing, higher-level fitness costs can be avoided

120
Q

how do biological subunits stay so cooperative?

A

many features of individual organisms prevent competition within an individual:
- prevents evolution within individuals
- align fitness interests across levels of organisation
- this ensures that many genes succeed by enhancing the fitness of the individual

121
Q

two ways in which biological subunits stay cooperative

A
  1. meiosis and mitosis:
    - ensures that alleles don’t compete within an individual
    - fair representation of gene variants among daughter cells
  2. development and multicellularity
    - starting from a single cell prevents initial competition among cell lineages
122
Q

what is fair meiosis?

A

meiosis provides a fair representation of an allele’s fitness effects on individuals

123
Q

define and describe meiotic drive

A
  • if an allele can bias its own transmission then it can spread to higher frequency even while reducing individual fitness
  • selfish genetic element relative to organism’s fitness interests
124
Q

give an example of meiotic drive and cheating Mendel’s law of segregation

A

drosophila segregation distorter locus (SD)
- almost all (95-99%) of offspring are Ss
- S allele prevents proper ‘s’ sperm formation
- counteracting restorer alleles are favoured at other genes in the genome to silence the S allele

125
Q

what is the evolutionary response to meiotic drive?

A

when cheating alleles spread, there is strong selection on rest of genome for suppression of cheating

126
Q

define and describe over-replication

A

transposable elements are self-replicating segments of DNA (transposons)
- TE replication is separated from cellular replication
- ensure their own over-representation in offspring

127
Q

two ways to cheat a fair meiosis

A
  • meiotic drive
  • over-replication
128
Q

how do genomes not explode from transposition?

A
  1. alleles arising elsewhere in genome that silence TES will be favoured by individual selection
    - mechanisms controlling DNA & histone methylation
    - piRNAs and RNA interference may have evolved as silencing mechanisms
  2. transposition-selection balance
    - transposition is a form of mutation that can disrupt a gene
    - natural selection against harmful effects on the organism reduces abundance of chromosome copies with most TES
    - abundance of TEs in an organism results from a balance between these opposing forces
129
Q

what can lead to rampant activation of transposable elements?

A

mutations in genes for DNA methylation:
- mutation in DDM1 gene reduces methylation
- this reactivates silenced TEs

130
Q

what experiments were done with C.Elegans and why?

A
  • cell lineage mapped from 1 cell zygote to 959 cells of adult
  • how do collections of cells maintain cooperation to make an organism?
131
Q

what features may inhibit unregulated cell division?

A

tumour suppression

132
Q

what makes it harder for collections of cells to stay cooperative?

A
  • somatic mutation is inevitable in long-lived multicellular organisms
  • some of those somatic mutations might be selectively favoured within an individual
133
Q

use cancer as an example of selfish cell lineages evolving within an individual

A
  • spreads commonly in tissue that is relatively undifferentiated
  • evolves resistance to treatment and the immune system
  • illustrates the short sightedness of the evolutionary process
134
Q

3 main methods in which evolution may be applied

A
  1. agricultural relevance; pesticide and herbicide resistance
  2. evolutionary medicine; evolution of resistance to antibiotics, evolution-proof vaccination
  3. global change and evolution; adapt or go extinct
135
Q

what is the problem with pests and evolution?

A
  • we use chemicals to combat pests and pathogens
  • we create strong selective pressure for resistance, with fitness advantage to resistant genotypes arising from mutation and gene flow
136
Q

why are weeds an issue for agriculture?

A
  • cause approx. 34% loss of crop yields annually
  • compete with crops for light, nutrients, space
  • usual solution is to spray with herbicides; however, weedy plants have repeatedly evolved resistance to herbicides
137
Q

where does herbicide resistance come from?

A
  1. pre-existing genetic variation in the population
  2. new mutations - in very large populations new, simple mutations may be introduced at a high rate
  3. gene flow - epidemic spread of resistance from one region to the next
138
Q

what type of weeds has the greater pre-existing resistance variation?

A

outcrossing weeds have more pre-existing resistance variation than selfing weeds

139
Q

how can herbicide resistance be stopped

A
  1. multi-herbicide treatment
    - makes new adaptation less likely
    - requires more complex adaptation
  2. rotation of different kinds of herbicides
    - weeds regularly hit by different selection pressures
    - but could select for generalised resistance
140
Q

give a graph for time vs population size of endangered species and weedy plants

A
141
Q

what is the problem with malaria and mosquitoes?

A
  • malaria causes approximately 700,000 deaths annually
  • major prevention strategy is insecticides
  • strong selective pressure on mosquitoes has led to rapid evolution of resistance
142
Q

what could be evolution-proof solutions to malaria?

A
  • tailor insecticide application to knowledge of mosquito generation times and spacial distributions
  • goal: minimise selection for mosquito resistance while still reducing malaria transmission
143
Q

use HIV treatment as an example of evolution in medicine

A
  • multi-drug cocktails slow evolution of HIV resistance
  • single mutations unlikely to confer resistance to multiple drugs with different mechanisms of action
  • lower viral loads make multiple mutations less likely
144
Q

describe evolutionarily informed cancer treatment

A
  1. strong, prolonged selection pressures using the same chemotherapy drugs - may not be the best solution as it selects for resistance
  2. cycling drugs, multi drug cocktails, lower drugs - may be a better option but ethical considerations make tests of theory for human application challenging
145
Q

describe environmental change as a problem

A
  • loss of habitat
  • habitat fragmentation
  • altered abiotic conditions (temperature, precipitation, pH)
  • altered biotic composition (transport of species, invasive species)
146
Q

define extinction

A

permanent elimination of a species

147
Q

genetic issues in conservation biology caused by environmental change

A
  • loss of genetic diversity
  • loss of heterozygosity
  • inbreeding depression
  • fixation of deleterious alleles
  • inability of populations to adapt
148
Q

probability of evolutionary rescue from adaptation depends on

A
  • population size
  • beneficial mutation rate
  • how much fitness was reduced

BIO120 (61 decks)

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