1
Q
allele frequency equation
A
of copies of a specific allele in a population / total # of all alleles for that gene in the population
2
Q
genotype frequency equation
A
of individuals with a particular genotype in a population / total # of individuals in the population
3
Q
allele
A
version of a gene each parent gives
4
Q
conditions for hardy-weinberg equilibrium
A
- no new mutations occur
- no natural selection occurs
- population is so large that allele frequencies don’t change because of random sampling error
- no migration between different population
- random mating
5
Q
evidence of evolutionary change
A
6
Q
if frequencies are not in equilibrium
A
7
Q
natural selection patterns
A
- directional
- stabilizing
- diversifying
- balancing
8
Q
directional
A
individuals at one extreme of a phenotypic range have greater reproductive success in a particular environment
9
Q
imitators
A
new allele with higher fitness are introduced
10
Q
longterm effect
A
if homozygotes with the favorable allele have the highest fitness, then the allele will dominate in the population
11
Q
stabilizing
A
favors the common phenotypes & selects against rares for ensurance of survival
12
Q
diversifying
A
favors survival of 2 or more phenotypes that produce different phenotypes (happens in diverse enviornments)
13
Q
phenotype
A
observable traits or characteristics of an organism that
14
Q
balancing
A
when nature keeps different versions of a gene around instead of just picking one
15
Q
what does balencing maintain?
A
genetic diversity
16
Q
two common ways of balancing
A
- heterozygote advantage (single gene)
-negative frequency (dependent selection)
17
Q
heterozygote advantage (single gene)
A
person with different versions of a gene is healthier
18
Q
negative frequency (dependent selection)
A
the rarer a gene is the better it does
19
Q
are genes normally polymorphic
A
yes
20
Q
polymorphism
A
presence of 2 or more variants or traits within a population
21
Q
what 5 factors caused evolution?
A
- genetic drift
- bottle neck
- founders effect
- migration/ gene flow
- nonrandom mating
22
Q
genetic drift
A
change in frequency of an existing gene variant in the population because of random chance
23
Q
bottleneck
A
occurs when a population size is SIGNIFICANTLY reduced for at least one generation
24
Q
what does bottleneck lead to?
A
loss of genetic diversity
25
darwin & wallace said existing life forms came from the modification of pre-existing life forms through interaction of what interacting factors?
- genetic migration
- natural selection
26
early ideas thought life forms as..?
unchanging
27
who proposed the idea of inheritance of acquired characteristics
jean baptiste lamarck
28
examples of evidence of the processes of biological evolution
selective breeding & homologous structures
29
descent with modification through variation & natural selection describe what of darwins theories
evolution
30
organism that displays features of an ancestral form and form of the more modern descendants is what form?
transitional
31
according to lamarck, species changed over time by altering their behavior in response to the environment resulting in
acquired traits
32
biogeography
study of geographic distribution of modern and extinctg species
33
Galapagos finches feeding habits
Cactus finches
Ground finches
Tree finches
cactus: probing beaks for fruits
ground: crushing beaks for seeds
trees: groping beak for insects
34
convergent evolution
35
what features does a transitional form display?
features of the ancestral forms and modern descendants
36
in selective breeding, artificial selection modifies domesticated species to produce traits that are...?
desirable from human perspective
37
study of distribution of modern and extinct species around the world is known as...?
biogeography
38
gene pool
all alleles for every population collectively makeup it up
39
what are the examples of the process of biological evolution?
biogeography
40
group of individuals of the same species that occupy the same environment and can interbreed with each other
population
41
similarity in an anatomical, developmental, or molecular feature that occurs due to descent from a common ancestor is a
homologous
42
An allele frequency describes the frequency at which a particular (...)
occurs within a population.
allele
43
what is a source of new genetic variations in a population
random mutation
44
Traits become more common in the population by an evolutionary mechanism called (...) through which individuals with heritable, favorable traits have increased survival and reproduction.
natural selection
45
Gene duplication and horizontal gene transfer are sources of new genetic
variation
46
What are sources of new genetic variation in populations?
horizontal gene transfer, random mutation
47
What does genetic drift select for?
no particular allele
48
Fitness is the relative likelihood that a
(...) will contribute to the gene pool of the next generation
genotype
49
are genes usually polymorphic?
yes
50
genetic drift may alter allele frequencies when the size of a population dramatically (...). give examples too
decreases (ex. bottleneck, founders effect)
51
does genetic drift favor loss or fixation of an allele?
yes
52
founders effect
small groups of individuals separate from the larger population and establishes new colony
53
migration/ gene flow
transfer of alleles into or out a population
54
migration/gene flow happens when?
individuals migrate between populations with different allele frequency
55
does migration/ gene flow reduce frequencies between 2 populations
yes
56
nonrandom mating
not choosing mates strategically (doesn't matter phenotype or genotype)
57
genotype
genetic makeup of an organism
58
random mating is a condition of what?
hardy- weignburg equilibrium
59
forms of nonrandom mating
- assertive
- disassortive
- inbreeding
60
assertive
individuals with similar phenotypes are more likely to mate
61
assertive nonrandom mating decreases what?
heterozygotes
62
disassortive
individuals without similar phenotypes mate (this is preferred)
63
dissortive nonrandom mating (...) heterozygotes?
increases
64
inbreeding doesn't favor an allele but...
increases homozygous liklihood
64
inbreeding
2 genetically related individuals mating
65
inbreeding nonrandom mating may have negative affects or may have...
recessive alleles
66
monomorphic gene
predominantly single allele
67
empirical thought
relies on observation to form an idea/ hypothesis
68
polymorphic gene
2 or more alleles with a frequency of > 1 %
69
jean baptiste lamarack popularized the idea that
species change over generations by adapting to new enviornments
70
lamarck also thought organisms alter behavior in response to
enviornmental changes
71
behavioral changes modify traits & hypothesized that
they were inherited by offspring
72
2 main hypothesis about geology
- catastrophism
- uniformitarianism
73
catastrophism was popularized by who
george cuvier
74
catastrophism
earth mostly was shaped by sudden violent events
75
james hutton proposed what?
uniformitarianism
76
uniformitarianism was popularized by who
charles lyell
77
uniformitarianism
changes in earth is directly caused by recurring events
78
who proposed "existing life forms resulted from modification of pre-existing life forms"
darwin and wallace
79
darwins theory of descent with modification through what?
- natural selection
-variation
80
types of observation
- selective breeding
- convergent evolution
- biogeography
- fossil record
- homology
81
selective breeding
breeders choose the parents with desirable traits
82
selective breeding is also known as
artificial breeding
83
convergent evolution
2 different species from different lineages become anatomically similar because of the similar environment
84
biogeography
unique species found on islands & other remote areas because they evolved in isolation
85
fossil record
fossils compared according to age (oldest- youngest)
86
homology
similarity because of common ancestor
87
what are the 3 homologies
- anatomical
- developmental
- molecular
88
anatomical
structures are anatomically similar to each other because they evolved from similar structures and common ancestors
89
developmental
analysis of embryonic development often reveals features that point to post evolutionary relationships
90
molecular
certain characteristics are found in all living cells
90
what homology suggests that all modern species come from an interrelated group of common ancestors
molecular
91
transitional form aka
Roasea
91
endemic
naturally only found in particular locations
92
transitional forms
intermediate state between an ancestral form of its descendants
92
analogous structures aka
convergent traits
93
island usually have what?
endemic organisms
94
analogous structures/ convergent traits
characteristics have came independently 2 or more time because different species had similar types of environments
95
sexual selection
individuals with certain traits are more likely to have successful reproduction
96
sexual dimorphism
difference between morphologies of 2 sexes within species
97
intrasexual selection
members of one sex compete with each other to mate
98
intrasexual selection is usually what sex?
males
99
intersexual selection
choosing mates from other sex based on desirable traits
100
intersexual selection is usually what sex?
females
101
who proposed that much of DNA sequence variation seen in genes in natural population is the result of genetic drift rather than natural selection?
motoo kimura
102
neutral theory of evolution
most evolutionary changes at molecular level are caused by ransom genetic drift of mutant alleles that are selectively neutral rather than natural selection
103
neutral variation
different alleles font affect organisms fitness
104
in neutral variation. whether an individual carries one allele or another it...
doesnt influence survival reproduction
104
early ideas suggest life forms are
fixed and unchanging
Bio 105
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