test 1 Flashcards
(159 cards)
1
Q
a structure that has no apparent function in one species, yet it is homologous to a functional organ in another (human embryos tails that disintegrate before birth)
A
vestigial
2
Q
effects of gene flow
A
a new individual will add new alleles to the original population, reducing genetic differences between the two groups
3
Q
how many mass extinctions have we seen in the past 500 million years?
A
5
4
Q
used to assign an age to a fossil by testing either the fossil itself or the sediments above and below the fossil, either way, the dates are usually expressed in relation to the present
A
absolute dating
5
Q
hybrid inviability (hybrid embryo may die before reaching reproductive maturity), hybrid breakdown (some species produce hybrid offspring that are fertile when those hybrids produce their offspring may have abnormalities), hybrid infertility (some hybrids are infertile)
A
postzygotic barrier examples
6
Q
t or f: Mendel was also studying inheritance at the same time as Darwin but neither of them knew of each other
A
true
7
Q
hypothesis on how life developed from single-cell to multi-cell
A
the origin of multicellularity ushered in the possibility of specialized cells, which allowed for new features such as attachment to a surface or an upright orientation
8
Q
population, or group of populations, whose members can interbreed and produce fertile offspring
A
how Mayr described biological species
9
Q
occurs when extreme phenotypes are less fit than the optimal intermediate phenotype
A
stabilizing selection
10
Q
describes the evolutionary tree that requires the fewest steps to construct from a set of observations
A
parsimonious tree
11
Q
occurs when all members of a species have died, if speciation is the birth of a species extinction represents its death
A
extinction
12
Q
how do environmental changes affect natural selection?
A
as the environments changes, organisms have to change with it in order to continue their bloodline, the phenotype that is “best” depends entirely on the time and place
13
Q
theory that life’s history has been characterized by bursts of rapid evolution interrupting long periods of little change
A
punctuated equilibrium
14
Q
recognize adaptation from an evolutionary perspective
A
individuals with the best adaptations to their existing environment are most likely to reproduce and pass their advantage to their offspring
15
Q
when did life first form on earth and what were they?
A
prokaryotic cells 4.2-3.8 BYA
16
Q
produces similar adaptations in organisms that do not share the same evolutionary lineage (desert plants)
A
convergent evolution
17
Q
which period is known as the age of amphibians?
A
Carboniferous (354-290 MYA) (Paleozoic era)
18
Q
the members of one sex choose their mates from among multiple individuals of the opposite sex (female birds choosing pretty male birds)
A
intersexual selection
19
Q
two or more extreme phenotypes are fitter than the intermediate phenotype
A
disruptive selection
20
Q
selective breeding strategy in which a human allows only organisms with desired traits to reproduce
A
artificial selection
21
Q
number of individuals of one genotype, divided by the number of individuals in the population
A
genotype frequency
22
Q
which era is known as the age of mammals?
A
Cenozoic era (65-.01 MYA) includes Paleogene, Neogene, and Quaternary
23
Q
part of a population enters a new habitat bordering the range of the parent species
A
parapatric speciation
24
Q
t or f: reproductive barriers can lead to three types of speciation, allopatric, parapatric, and sympatric
A
true
25
a large-scale evolutionary change
macroevolution
26
how did people respond to Darwin's ideas?
some people embraced them, but others with religious domination had a clash with their beliefs and others may just have not liked the idea that humans were just another species competing for resources
27
calculated as the number of copies of that allele, divided by the total number of alleles in the population (the rate at which a specific allele appears within a population)
allele frequencies
28
who proposed a theory of uniformitarianism?
James Hutton
29
suggests that genetic mutations create heritable variation and that this variation is the raw material upon which natural selection acts
modern evolutionary synthesis
30
what are the levels of groups (taxa) used in the hierarchical system by Linnaeus
domain, kingdom, phylum, class, order, family, genus, species
31
inherited attributes that resemble those of the ancestor of a group
ancestral characters
32
a single species gives rise to multiple specialized forms in a relatively short time
adaptive radiation
33
held that evolution proceeds in small, incremental changes over many generations
gradualism
34
occurs when a populations size drops rapidly over a short period; randomly eliminates many alleles that were present in the larger ancestral population
bottleneck effect
35
When did the largest mass extinction occur?
at the end of the Paleozoic era, in the Permian
36
the time it takes for half of the atoms in a sample of a radioactive substance to decay (if an isotopes ____ is one year, 50% of the radioactive atoms in a sample with have decayed in a year, in another year, half of the remaining radioactive atoms will decay, leaving 25% and so on
half-life
37
1. the biological species concept cannot apply to asexually reproducing organisms (bacteria, archaea, and many fungi and protists)
2. it is impossible to apply the biological species definition to extinct organisms known only from fossils
3. some types of organisms have the potential to interbreed in captivity, but they do not do so in nature
4. reproductive isolation is not always absolute
problems with Linnaeus's biological species definition (did not consider the role of evolutionary relationships)
38
reduce the fitness of a hybrid offspring if fertilization does occur
postzygotic reproductive barrier
39
what was the name of Darwin's book and what impact did it have?
Darwin's book was 490 pages and was called "On the Origin of Species by Means of Natural Selection, or Preservation of Favoured Races in the Struggle for Life, and it would form the underpinning of modern life science
40
t or f: fossils became abundant at the start of the Phanerozoic
true
41
the theory that suggests that a series of brief, violent, global upheavals such as enormous floods, volcanic eruptions, and earthquakes were responsible for most geological formations
catastrophism
42
t or f: natural populations often violate HW equilibrium
true
43
what are the three domains of life?
archaea, bacteria, and eukarya
44
- biological evolution explains the origin of life
- evolution is a random process
- in a changing environment, all individuals in a population simultaneously develop beneficial adaptations
misconceptions of natural selection
45
who was the first to openly suggest that closely related species arose from a common ancestor and were changing?
George-Louis Buffon
46
a phylogenetic system that defines groups based on characters that indicate shared ancestry
cladistics
47
- the vast majority of organisms never leave a fossil trace
- erosion (movement of earth's continental plates) has destroyed many fossils that did form
- scientists are unlikely to ever discover the many fossils that must be buried deep in the Earth or submerged underwater
reasons why the fossil record is incomplete
48
what are the two HW equations?
p + q =1
p2 + 2pq + q2 = 1
49
a change in allele frequencies that occurs purely by chance, tends to eliminate alleles from a population
genetic drift
50
who was convinced of catastrophism and used his knowledge of anatomy to identify fossils and describe the similarities amongst organisms? As well as being the first to recognize the principle of superstition.
Georges-Cuvier
51
t or f: natural selection is an evolutionary mechanism
true
52
the study of the evolutionary relationship among species
phylogenetics
53
the theory that suggested that processes of erosion and sedimentation that act in modern times have also occurred in the past, producing profound changes in the earth over time
uniformitarianism
54
to or f: low genetic diversity in small populations can increase chance of extinction
true
55
T or F: populations evolve, not individuals alone
true
56
interbreeding members of the same species occupying the same region
population
57
which era is known as the age of reptiles?
The Mesozoic era (248-65 MYA) includes Triassic, Jurassic, and Cretaceous
58
phylogenetic (evolutionary) trees
phylogenies
59
temporal isolation (two species that share a habitat will not mate because they are active at different times or reach reproductive maturity at different times), behavioral isolation (behavioral differences may prevent two species from mating), mechanical isolation (any change in the shape of the gamete delivering or receiving structure may prevent interbreeding), gametic isolation (sperm cannot fertilize an egg cell), ecological isolation (difference in habitat preference separates two pops.)
prezygotic barrier examples
60
deep water trench that separated the islands of Borner + Java and Sulawesi
Wallace's line
61
the small, generation-by-generation changes to a population’s gene pool
microevolution
62
t or f: adaptive radiation is common on islands
true
63
t or f: natural selection acts on existing mutation, and only heritable mutations affect evolution
true
64
when did homo sapiens appear
200,000 years ago
65
type of natural selection resulting from variation in the ability to obtain mates, and it occurs in two forms
sexual selection
66
t or f: natural selection eliminates poorly adapted phenotypes
true
67
a new species arise while living in the same physical area as its parent species
sympatric speciation
68
earth’s surface consists of several rigid layers, called tectonic plates, that move in response to forces acting deep within the planet
theory of plate tectonics
69
is the science of describing, naming, and classifying species
taxonomy
70
some parts of an organism’s body may appear superficially similar in structure and function but they evolved independently of one another (wings of birds and butterflies, same function but not the same materials or organization)
analogous
71
when a great number of species disappeared in a relatively short time
mass extinction
72
which era did the age of fish and amphibians occur?
the Paleozoic era
73
t or f: natural selection requires limited resources and genetic diversity
true
74
a highly unlikely situation where allele frequencies and genotype frequencies do not change from one generation to the next
Hardy-Weinberg Equilibrium
75
what were Lyell's ideas about the age of Earth and fossils?
Lyell believed that the gradual changes in some organisms could be represented in successive fossil layers
76
the study of fossil remains or other clues to past life
paleontology
77
the greater the similarity between two modern species, the closer their evolutionary relationship
assumption of molecular evolution
78
1. every genome has limited potential, imposed by its evolutionary history
2. no population contains every allele needed to confront every possible change in the environment
3. disasters like floods and volcanic eruptions can eliminate the best alleles combinations, simply by chance
4. some harmful genetic traits are out of natural selection's reach like Huntingtons disease
factors that limit natural selection
79
describes how self-replicating RNA may have been the first independent precursor to life on earth
RNA world
80
the members of one sex compete among themselves for access to the opposite sex (male ox beetles fight during mating season)
intrasexual selection
81
how are humans contributing to a 6th possible mass extinction
destroying and polluting habitats, introducing alien species that compete with the native species, and harvesting species faster than they can reproduce
82
the study of the distribution of species across the planet
biogeography
83
suggests that meteorites or comets have crashed to Earth, sending dust, soot, and other debris into the sky, blocking sunlight and triggering extinctions in a deadly chain reaction. without sunlight the plants died, the animals likewise died without good and shelter
impact theory
84
places a fossil into a sequence of events without assigning it a specific age
relative dating
85
contrast natural and artificial selection
natural selection is something that happens naturally along with changes in the environment, causing the best attributes to be further reproduced; artificial selection is when humans selectively breed other animals in order to benefit them, in nature these attributes would not have ever happened if not for human intervention
86
features that provide a selective advantage because they improve an organism’s ability to survive and reproduce
adaptations
87
a difference in appearance between males and females (one sex may be much larger or more colorful)
sexual dimorphism
88
what are the five assumptions of the HW Equilibrium?
- natural selection does not occur
- mutations do not occur
- the population is indefinitely large
- individuals mate at random
- individuals do not migrate into or out of the population
89
a group at any rank
taxon
90
how can cytochrome c be used to study molecular evolution
the more recent the shared ancestor with humans, the fewer the differences in the amino acid sequence for the respiratory protein cytochrome c
91
1. few individuals may colonize a new habitat that simultaneously selects for different phenotypes, eventually leading to reproductive isolation
2. a new adaptation may contribute to reproductive success in a wide variety of environments
3. after a catastrophe wipes out many species, the survivors diversify as they exploit the changed environment
three ways adaptive radiation can occur
92
when fossils of all major phyla of animals appeared within a few million years of one another in the Cambrian seas
Cambrian Explosion
93
basis for comparison in a cladistics analysis that consists of comparator organisms that are not part of the group being studied
outgroup
94
moves alleles from one population to another (doesn't require the movement of entire individuals [wind carrying plant seeds])
gene flow
95
when did mammals and flowering plants arise?
the Mesozoic
96
the location of earth's continents has changed with time, due to shifting tectonic plates
continental drift
97
was the first investigator to give every species a two-word name (genus [broader classification] and a second word that designates the species)
Carolus Linnaeus
98
define evolution in terms of allele frequencies
evolution is a change in the frequency of an allele in a population
99
t or f: multicellularity arose independently in multiple lineages of protists and fungi
true
100
what do p2, 2pq, and q2 represent in HW equation?
represents the genotype frequencies of homozygous dominant (p2), heterozygous (2pq), and homozygous recessive (q2)
101
population, or group of populations, whose members can interbreed and produce fertile offspring
speciation
102
over many generations, a population's characteristics can change by natural selection, even giving rise to new species
descent with modification
103
uses of the HW equilibrium
we can use the HW equations to estimate allele frequencies based on the known frequency of one genotype
104
any evidence of an organism from more than 10k years ago (end of Pleistocene epoch)
fossil
105
when did earth originate?
4.6 billion years ago
106
uses DNA sequences to estimate the time when multiple organisms diverged from a common ancestor
molecular clock
107
t or f: photosynthesis using water led to O2 accumulation on earth
true
108
What likely caused the Cretaceous mass extinction?
an asteroid impact near the Yucatan peninsula, photosynthesis was non-existent for 3 years
109
multiple alleles of a gene persist indefinitely in the population at more or less constant frequencies indefinitely (the persistence of multiple alleles in a population)
balanced polymorphism
110
what were Darwin's three observations? what did he infer?
1. individuals in a species are different from one another, and at least some of this variation is heritable
2. essential sources such as food and space are limited in every habitat
3. in every population, more offspring are born than can survive
he inferred that organisms engage in a struggle for existence, they must compete for resources; he also inferred that those individuals with the most adaptive traits would be most likely to win the competition; his last inference was that over many generations, natural selection could change a population or give rise to a new one
111
genes that encode proteins that regulate development (when mutated, leads to organisms with structures in the wrong places)
homoeotic genes
112
t or f: new species arise due to reproductive isolation because they can no longer breed and produce fertile offspring with the rest of the population
true
113
who renewed the argument for uniformitarianism, suggesting that natural processes are slow and steady and that Earth is much older than 6000 years? (one conclusion from his contribution is that gradual changes in some organisms could be represented in successive fossil layers
Charles Lyell
114
which period is known as the age of fishes?
Devonian (417-354 MYA) (Paleozoic era)
115
what does it mean for a trait to be selectively neutral?
they neither increase nor decrease reproductive success
116
what were the observations from Darwin on his journey?
heritable variations (no two individuals in a species are exactly alike, some of this variation is heritable), limited resources, and overproduction of offspring (more individuals are born that survive to reproduce)
117
when did eukaryotic cells arise?
1.5 BYA
118
when individuals with certain genotypes—those that are best suited to the environment—have greater reproductive success than other individuals
natural selection
119
t or f: natural selection does not have a goal
true, natural selection does not have a goal
120
occurs when a small group of individuals leaves its home population and establishes a new, isolated settlement individuals
founder effect
121
a new species forms when a geographical barrier physically separates a population into two groups that cannot interbreed, barrier may be a river, desert, glacier
allopatric speciation
122
example of heterozygote advantage
sickle cell disease
123
why are mutations the raw material for evolution?
because genes contribute to phenotypes, and natural selection acts on phenotypes
124
the idea that lower layers of rock (and the fossils they contain) are much older than those above them
principle of superstition
125
t or f: changes in regulatory DNA can affect body features
true
126
descent [inheritance] with modification [changes from gen. to gen.]
evolution
127
t or f: sexual reproduction amplifies variability in a species
true
128
since evolution can explain how populations become different over time, Wallace’s observation led to the prediction that the regions must have been separated for a long time; later, a deep trench was discovered that separated the island even when sea levels fell, preventing gene flow between organisms on each side
this is why marsupials of Australia are diverse and restricted to mainly Australia
129
results from the steady, gradual loss of species due to normal evolutionary processes
background extinction rate
130
choosing mates based on location, physical traits, or other factors
nonrandom mating
131
How did Wallace propose natural selection?
he had observed the diverse animals of South America and Southeast Asia, and his manuscript independently proposed that natural selection was the driving force of evolution
132
who was the taxonomic hierarchy developed by
Linnaeus
133
has features that are different from those found in the group’s ancestor
derived characters
134
examples of artificial selection
humans breed dogs to look a specific way, also selectively breeding farm animals like cows, chickens, pigs, etc
135
the three eras of the Phanerozoic
Paleozoic, Mesozoic, and Cenozoic
136
how do microevolutionary changes lead to genetic divergence
mutations, natural selection, and genetic drift are microevolutionary changes that can lead to divergence with the accumulation of enough differences in their gene pools, they can no longer produce fertile offspring
137
the entire collection of genes and alleles
gene pool
138
study of the classification, therefore, incorporates two interrelated specialties: taxonomy and phylogenetics
systematics
139
t or f: genetic drift is more likely to affect small populations
true
140
what lines of evidence are used to form phylogenetic trees?
anatomical features of fossils and existing organisms, also behaviors, physiological adaptations, and molecular sequences
141
(occurs when the number of sets of chromosomes increases) sometimes arises when gametes from two different species fuse, and can also occur when meiosis fails [rare in animals, common in plants]
polyploidy
142
what are the lines of evidence of evolution?
fossils and biogeographical studies provided the original evidence but comparisons of embryonic development and anatomical structures provided additional supporting data
143
large-scale evolutionary events, such as the appearance of a new species
macroevolution
144
prevent the formation of a zygote
prezygotic reproductive barrier
145
what were Lamarck's ideas about the origin of the species?
organisms that used one part of their body repeatedly would increase their abilities, conversely, disuse would weaken an organ until it disappeared
146
how does natural selection apply to the diversity of finches on the islands?
natural selection applies to the finches because on different islands there are different environments in which some attributes may be more qualified than others to live on that island which is why the finches had different beak shapes based on where they were on the island and what kind of food they could consume
147
similar in structure or position because of common ancestry (homologous forelimbs in humans, lions, and birds)
homologous
148
one extreme phenotype is fittest, and the environment selects against others
directional selection
149
occurs when an individual with two different alleles for a gene (heterozygotes) has greater fitness than those whose two alleles are identical (homozygotes)
heterozygote advantage
150
proposes that mitochondria and chloroplasts originated as free-living bacteria that began living inside other cells
endosymbiotic theory
151
a treelike diagram built using shared derived characters
cladogram
152
refers to an organisms genetic contribution to the next generation
fitness
153
t or f: microevolution can lead to macroevolution
true
154
how did thomas malthus inspire Darwin's work?
Malthus wrote an essay that stated that food availability, disease, and war limit the size of the human population, which made Darwin believe the same could happen to other organisms
155
what do p and q represent in HW equation?
represent the allele frequencies (p = dominant; q = recessive)
156
evidence of the impact theory
iridium on earth, rare on earth but common in meteorites
157
who proposed the first scientifically testable evolutionary theory? reasoning that organisms that used one part of their body repeatedly would increase their abilities, conversely, disuse would weaken an organ until it disappeared
Jean Baptiste de Lamarck
158
t or f: development reveals homology
true
159
t or f: fitness depends on reproduction
true
