Last part of 206 Flashcards
1
Q
Species
A
Smallest evolutionarily independent unit
2
Q
3 parts of speciation
A
- Reduced gene flow
- Genetic divergence
- Reproductive isolation
3
Q
3 parts of reduced gene flow
A
- Physical (geographic/allopatric)
- ecological
- sexual
4
Q
2 parts of physical isolation
A
- vicariance
- dispersal
5
Q
2 parts of genetic divergence
A
- genetic drift
- adaptation to different habitats/resources
6
Q
3 parts of reproductive isolation
A
- incidental genetic incompatibilities
- reinforcement
- sexual selection
7
Q
Vicariance
A
- splitting event
8
Q
Dispersal
A
- rare
- due to natural events like storms
9
Q
Ecological isolation
A
- breeding habitat, time, behaviour, morphology (ex stickleback)
10
Q
Sexual selection reduces gene flow if
A
- linkage between sexually selected trait and the preference for the trait
- variation for either the trait or the preference
11
Q
Genetic divergence
A
- Bottleneck or founder effect, needs super strong drift
- low genetic variation
12
Q
Ecological speciation
A
adaptation to diff habitats/environments
parallel adaptation in marine and freshwater sticklebacks
13
Q
Reproductive isolation 2 times
A
Prezygotic
Postzygotic
14
Q
Incidental genetic incompatibilities due to drift or selection
A
Alleles don’t work together (Bateson dobzhansky-muller)
15
Q
Reinforcement
A
Selection against offspring of mixed matings
Basically postzygotic incompatibilities unknown to the animal so selection forms exaggerated differences
16
Q
What is needed for pops to diverge with gene flow
A
selection needs to be higher than migration
17
Q
Sympatric speciation
A
In 1 area
18
Q
Parapatric speciation
A
adjacent areas
19
Q
Hybridization
A
breeding between individuals from genetically different populations or species
20
Q
Introgression
A
Transfer of genetic material between individuals from genetically different populations or species facilitated by hybridization
21
Q
Hybrid fitness increase intrinsic causes
A
- masking of deleterious recessive alleles
- Increase in heterozygote advantage
22
Q
Hybrid fitness increase extrinsic cause
A
- introduction of new adaptations
23
Q
Hybrid fitness decrease intrinsic causes
A
- chromosomal incompatibilities
- loss of coadapted gene complexes
24
Q
Hybrid fitness decrease extrinsic cause
A
- loss of local adaptations (goats that died)
25
Hybrid low fitness
Reinforcement - finalization of reproductive isolation
26
Hybrid reproductively isolated from parent species
- polyploid hybrid speciation (ploidy increased, in plants lots)
- homoploid hybrid speciation (ploidy doesn't change. lonely finch with lots of inbreeding)
27
Hybrid and offspring and grand-offspring high fitness (heterosis)
Reverse speciation/adaptive introgression (mallard duck with grey duck/insecticide resistance in mosquitoes)
28
Hybrid has high fitness in hybrid zone
Stable hybrid zone
29
Adaptive radiation
rapid proliferation of new species from single ancestral species
sympatric
30
Darwin finches speciation type
Allopatric? evolved on separate islands and spread
Sympatric? In parallel within each island
3 Species with alot of admixture
Due to beak
31
Tapirus distribution
weird
| originated in western asia and then spread everywhere else
32
Biogeography
study of where organisms live and how they got there
33
phylogeography
study of geographic distribution of evolutionary lineages, use of evolutionary trees to answer questions about distribution of organisms
34
Why are they where they are
Speciation in situ (vicariance)
| Dispersal
35
Why are they not where theyre not
Range limited by barriers to dispersal, fundamental ecological niche, biotic interactions
36
5 effects of climate change
- distribution shift
- declining habitat size
- dispersal barrier
- limited dispersal ability
- range expansion (rare)
37
Prevents fundamental niches from expanding through adaptation (stasis promotion)
- Migrational load/gene swamping/ maladaptive introgression
- genetic variation
- genomic/developmental constraints
38
Where species diversity is high
at low altitudes
areas of high primary productivity
areas with moderate disturbance rate
larger islands and continents
39
phyletic gradualism
morphological evolution is gradual and unrelated to speciation
40
Saltation
sudden changes in morphology
41
Stasis
no changes
42
Punctuated equilibrium
long stasis and quick saltation together
43
causes of punctuated equilibrium 3
- artifact of fossil record
- extreme pattern resulting from random processes
- macroevolution involves species selection
44
fossil record to demonstrate punctuated equilibrium needs
- species and phylogony defined independently of morphology
| - dense sampling from many locations
45
What causes stasis
- kind of stabilizing selection/niche conservation
| - definitely genomic and development constraints
46
what causes saltation
ecological release and evolutionary innovation
47
3 ways evolutionary innovations arise
- modularity
- specialization
- co-option (exaptation)
48
Modularity
- made of modules
- key innovations arise in changes of modules in number or use
- Heterochrony
- Heterotopy
- allometry
49
Heterochrony
changes in timing of development
50
Heterotopy
Changes in spatial relationships among part
51
allometry
changes in growth rates of parts
52
specialization
willinston's law
| against redundance
53
willinston's law
parts in organism tend toward reduction in number with fewer parts very specialized
54
co-option
modification of existing protein/structure/behaviour for a new function
55
hox genes (homeotic)
set up segments with developmental fates
| serial expressions
56
Hox genes duplications
1 st made chordates and 2nd made vertebrates
57
Complex systems evolved
bringing different regulatory genes and their networks together to not have just 5% of a structure
58
Spinnerets are what
serial homologs of pedipalps and limbs
59
How different are humans and chimps
1% genetic divergence
60
3 hypotheses of humans arising
african replacement
multiregional evolution
hybridization and assimilation (this one)
61
Can selection explain deviant social behaviour
yes. Evolutionary psychiatry like risk of parental homicide is higher for stepchildren
62
Why do genetic diseases exist and persist
- mutation
- founder effects
- heterozygote advantage
- linkage
- adaptational lags
63
Is selection being eliminated by human ingenuity
- niche reconstruction
- memes
- coltural change
64
cultural change is like natural selection
1. individuals vary
2. variation is transmitted among individuals
3. some variants are more successful than others
65
Because mutation rate is high and generation time is low
biological evolution is lagging behind many aspects of cultural evolution leading to diseases of civilization
adaptational lag is partially mitigated but also exacerbated
66
Primary goal of conservation
maintenance of potential for pops to adapt, evolve and form new species
67
genetic problems in conservation management involve
careful delineation of genetic population units
conservation breeding programs
restoring natural gene flow
68
careful delineation of genetic pop units
cryptic species, evolutionarily significant units, management units
69
cryptic
look the same but they're different
70
evolutionarily sig units
genetically isolated pops
71
management units
diff birth or death rates, different threats
72
conservation breeding programs
germ plasm banking
captive breeding
in situ breeding management
73
restoring natural gene flow
habitat corridors
translocating individuals/ seeds
eliminating alien species
74
Genetics help understand
ecology, monitoring populations, law enforcement
75
population decline genetic results
non random mating
| loss of adaptive potential
76
nonrandom mating
inbreeding depression
| hybridization inihiliation
77
loss of adaptive potential due to
loss of genetic additive variation
| increase in genetic drift
78
habitat degradation has 3 responses
phenotypic plasticity
migration
genetic adaptations
