Biology- Chapter 12
How did natural selection shape the evolution of finches on the Galápagos Islands?
Birds with different heritable differences were able to better survive and reproduce in different habitats.
Who was one of the first scientists to suggest that species arose from ancestors and were changing?
Buffon
Select all the statements about Charles Darwin that are correct.
Darwin studied similarities and differences among organisms and related them to geological observations. Darwin proposed that natural selection was a force that could change populations and give rise to new species.
A book written by Thomas Malthus that influenced Charles Darwin's formulation of natural selection was titled
Essay on the Principle of Population.
Darwin collected birds from the _______ Islands and took them back to England to study, where John Gould identified 13 species of birds called ______.
Galápagos; finches
Random mating, a large population, and no mutation, selection, migration, or nonrandom mating are all assumptions of
Hardy-Weinberg equilibrium.
Geological processes that occur today also occurred in the past, producing changes to Earth over time. This theory was proposed by ______ and is referred to as ______.
James Hutton; uniformitarianism
What scientist was the first to propose a mechanism for how species could change through repeated use or disuse of a body part?
Lamarck
Select the name of the scientist who first stated that the Earth was older than 6,000 years.
Lyell
What publication did Darwin read during his voyage on the HMS Beagle that convinced him of uniformitarianism and the old age of the Earth?
Lyell's Principles of Geology
Select all the reasonings of Charles Darwin that were influenced by Thomas Malthus's essay.
More individuals are born into a population than the habitat can support. Some individuals in a population are better able to obtain resources than others. There is variation in a population.
Select the correct statement about natural selection.
Natural selection does not have a goal of a perfect organism.
The shortened title of the book that Charles Darwin published in 1859 was
On the Origin of Species.
Select all the statements that describe Lamarck's ideas about the origin of species.
Organisms that use a body part repeatedly increase their abilities. Any physical changes that happen to the parents during their lives can be passed on to the next generation.
Select implications of Conover's and Munch's studies on selective forces of fish harvesting.
Protecting the largest fish from harvest would help favor fast-growing fish. Fisheries would benefit from both a minimum and maximum size limit for harvest.
Select observations and inferences that Charles Darwin made in support of natural selection.
There is competition among individuals for limited resources. Some individuals survive due to their inherited characteristics, making them more likely to reproduce. More individuals are born than can survive to reproduce. Organisms are varied and some variations are inherited. Natural selection can change the characteristics of a population over many generations.
Select all the key properties of evolutionary adaptations.
They can confer reproductive success. They are heritable.
Whose essay, describing how factors limit human population size, influenced Charles Darwin's ideas about variation and survival among individuals in a population?
Thomas Malthus
A gene pool is the collection of all of the genes and alleles of
a population
What describes the founder effect?
a small group of individuals establishes a new colony
A(n) ______ is a feature that provides a selective advantage to an organism because it improves its ability to survive and reproduce.
adaptation
Darwin noted that natural selection occurs because
adaptive traits that are heritable can pass to offspring and increase their survival and reproduction.
Select all of the following that occur in natural populations and that violate the assumptions of the Hardy-Weinberg equilibrium.
allele frequencies can change due to chance events mating is often nonrandom migration among populations occurs
The number of copies of an allele divided by the total number of alleles in a population is the
allele frequency.
In the state of Hardy-Weinberg equilibrium, allele frequencies
are not changing.
If humans are involved in perpetuating desired traits in organisms, the result is
artificial selection.
________selection occurs when humans select for desirable characteristics in crosses of dogs, horses, or other organisms, whereas __________selection occurs when environmental factors select for adaptive traits.
artificial; natural
Charles Darwin consulted John Gould about the birds that he had collected on the Galápagos Islands. Gould identified 13 distinct types of finches based on the birds'
bills
When a population's size drops rapidly over a short period, resulting in a loss of many alleles that were present in the larger ancestral population, this is referred to as the _____________effect.
bottleneck
When a population's size drops rapidly over a short period, resulting in a loss of many alleles that were present in the larger ancestral population, this is referred to as the ___________effect.
bottleneck
A type of genetic drift in which a population's size drops rapidly over a short period of time, causing the loss of many alleles, is called a
bottleneck effect.
Genetic drift is a change in allele frequencies that occurs by ______ and, unlike mutations, it tends to eliminate alleles from the population.
chance
Migration of individuals from one population to another
creates gene flow between populations.
Experiments conducted by Conover and Munch at Stony Brook University indicate that harvesting of large fish is acting as a selective force to
decrease average fish size in the population.
Gradual genetic changes in organisms from an ancestral species describes
descent with modification.
In sexual dimorphism, one sex is ______ than the other sex.
different in appearance
Selection for dark-winged moths in a population of moths with pigmentation that varies from light to dark is an example of _____ selection.
directional
Selection for one extreme phenotype in a population would be considered a type of natural selection called ______ selection.
directional
When two phenotypic extremes of a trait are being selectively favored, then a natural population is undergoing _______ selection.
disruptive
If a predator is more likely to prey upon fish that are brightest in color, then natural selection in this environment will favor
drabber fish.
Descent with modification describes the process of
evolution
Natural selection, mutation, genetic drift, nonrandom mating, and gene flow are all mechanisms of ______ and can change allele frequencies in populations.
evolution
One definition of ______ is "changes in traits from generation to generation."
evolution
__________ is defined as a change in allele frequencies in a population over time.
evolution
True or false: Charles Darwin was the first to attempt to explain how the diversity of life arose.
false
How does natural selection act to change allele frequencies?
favors phenotypes that increase reproductive success
Disruptive selection is a mechanism of natural selection that
favors two or more extreme phenotypes in a population.
The genetic contribution of an organism to the next generation is referred to as
fitness.
A genotype's ________is the number of individuals with that genotype, divided by the total size of the population.
frequency
In a population, each genotype's ______ is the number of individuals with that genotype, divided by the total size of the ______.
frequency; population
What describes how genetic drift occurs?
gain or loss of alleles by chance
___________flow is the movement of individuals or gametes into or out of a population.
gene
Select all of the following that are mechanisms of evolution and that can alter allele frequencies.
gene flow natural selection mutation
A precise definition of evolution is the
genetic change in a population over multiple generations.
In evolutionary terms, fitness of an organism is defined as an organism's
genetic contribution to the next generation.
A chance change in a population's allele frequencies, such as after a drastic reduction in population size, is the root of what force of evolution?
genetic drift
A change in allele frequencies that occurs by chance and that tends to eliminate alleles in a population rather than increase diversity is called
genetic drift.
In the Hardy-Weinberg equilibrium, the terms p2, 2pq, and q2 refer to
genotype frequencies in a population.
Lyell's idea about fossils and the age of the Earth led to the conclusion that
gradual changes occurred in some organisms and that these could be preserved in the fossil record.
As proposed by James Hutton, the theory of uniformitarianism states that
gradual geological processes such as erosion and sedimentation that act in modern times also occurred in the past.
Evolutionary theory
has developed over several centuries.
In artificial selection, ______ determines the traits that give individuals the greatest reproductive success.
human choice
When allele and genotype frequencies are not changing between generations, the population is said to be
in Hardy-Weinberg equilibrium.
Mate choice, such as in sexual selection,
leads to nonrandom mating.
Fossils present in ______ layers of rock are older.
lower
The principle of superposition explains the idea that ______ layers of rock, along with the fossils they contain, are older than the layers ______ them.
lower; above
Select all the examples of nonrandom mating.
mating only within a specific group mate choice based on social position choosing mates based on certain characteristics
In the 1930s, scientists unified natural selection and genetics into the
modern evolutionary synthesis.
Darwin reasoned that the variety of finch species found on the Galápagos Islands descended from a common ancestor. He used the phrase "descent with ________" to describe gradual genetic changes from the ancestral type.
modification
The only way that new genetic variants arise is through ______, which is the raw material of evolution.
mutation
What mechanism of evolution introduces new alleles into a population?
mutation
New alleles that might allow a bacterium to become resistant to an antibiotic arise through
mutation.
According to the modern evolutionary synthesis, what creates the variation upon which natural selection acts?
mutations
Charles Darwin's book titled On the Origin of Species proposed ______ as an evolutionary mechanism.
natural selection
Directional, disruptive, and stabilizing are all types of ______, in which certain phenotypes are favored over others.
natural selection
What occurs when environmental factors cause the differential reproductive success of individuals with particular genotypes?
natural selection
When the process of ______ takes place over billions of years, a simple organism can give rise to many different types of species, such that all species are related to each other through evolution.
natural selection
Natural selection can act to eliminate
nonadaptive phenotypes.
Rock layers at the bottom of a geologic deposit are the
oldest
After reading Malthus's essay, Darwin realized that
poorly adapted individuals would not survive if resources were limited.
Interbreeding members of the same species compose a _________.
population
Populations of peacocks, deer, and prairie chickens that use reproductive methods in which one individual picks a mate based on a particular characteristic would violate which Hardy-Weinberg equilibrium assumption?
random mating
In the bottleneck effect, what alleles are lost when a population's size drops is
random.
Select all of the following that are true about natural selection.
reproductive success of individuals differs occurs due to variation in environmental factors
Hardy-Weinberg equilibrium is seldom seen in natural populations because
selection takes place in natural systems.
What type of reproduction amplifies genetic variation by shuffling alleles and producing genetically different offspring?
sexual
A difference in the appearance between males and females of a species is called
sexual dimorphism.
What increases genetic variability within a species through shuffling and reshuffling of parental alleles to produce genetically different offspring?
sexual reproduction
Human birth weight is an example of a type of natural selection called _______ selection.
stabilizing
When the intermediate phenotype of a trait is being selected for and the extreme phenotypes are being selected against, the population is probably undergoing
stabilizing selection.
Cuvier thought that lower layers of rock were older than those above them. This principle describes
superposition.
One cause of genetic drift is _____, in which a small group of individuals leaves its home population and establishes a new, isolated settlement.
the founder effect