Chapter 22
evolutionary tree
A branching diagram that reflects a hypothesis about evolutionary relationships among groups of organisms.
embryos of dissimilar organisms, such as sharks and humans, resemble each other
A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that _____. mutations have a far more dramatic effect on embryos than on adult organisms embryos of dissimilar organisms, such as sharks and humans, resemble each other the embryological development of many plants and animals is almost identical all animals develop similar embryonic gills the more advanced the animal, the more slowly it develops
vestigial structure
A feature of an organism that is a historical remnant of a structure that served a function in the organism's ancestors.
homologs
A pair of chromosomes of the same length, centromere position, and staining pattern that possess genes for the same characters at corresponding loci. One homologous chromosome is inherited from the organism's father, the other from the mother.
Adult zooplankton will start to reach sexual maturity when they are still relatively small.
A population of zooplankton is exposed to a small number of predatory fish that feed on the larger-sized (adult) zooplankton. Which of the following predictions would most likely occur based on the principles of natural selection? The first and the third listed responses are both good predictions. The predatory fish will evolve smaller mouths so that they do not drive their prey to extinction. The predatory fish will evolve poor eyesight so as to preserve their food supply. Adult zooplankton will start to reach sexual maturity when they are still relatively small. The zooplankton will become sexually mature at larger sizes.
fossil
A preserved remnant or impression of an organism that lived in the past.
Uniformitarianism
A principle that geologic processes that occurred in the past can be explained by current geologic processes
natural selection
A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
stratum
A rock layer formed when new layers of sediment cover older ones and compress them.
population
A(n) __________ is the smallest unit that can evolve. adaptation community species population individual
produce similar patterns of evolutionary relatedness
According to the theory of evolution, anatomical and molecular homologies should __________. produce similar patterns of evolutionary relatedness link all of the species currently present on Earth be completely independent of each other yield very different hierarchical patterns be understood to have come about by chance alone
inherited characteristics of organisms that enhance their survival and reproduction in specific environments
Adaptations are defined as __________. characteristics that become larger and stronger during the lifetime of an organism inherited characteristics of organisms that enhance their survival and reproduction in specific environments characteristics that are not passed to offspring characteristics that are acquired during the lifetime of an organism inherited characteristics of organisms that reduce their survival and reproduction in specific environments characteristics that seem to have marginal, if any, importance to an organism
all organisms are descended from a single common ancestor
All known organisms transcribe genetic information to protein molecules via the same genetic code. This finding strongly supports the hypothesis that __________. all organisms are descended from a single common ancestor None of the listed responses is correct. there's only one possible way to encode information in a macromolecule the genetic code will never be broken the earliest macromolecules probably arose when lightning struck an oxygen-free atmosphere
dissimilar organisms might have evolved from a distant, common ancestor
An important challenge to traditional (pre-1860) ideas about species was the observation that seemingly dissimilar organisms such as hummingbirds, humans, and whales have similar skeletal structures. This most directly suggested to biologists that __________. only the best-adapted organisms can survive advantageous changes can be passed along to offspring dissimilar organisms might have evolved from a distant, common ancestor most evolution occurs rapidly following a mass extinction All of the listed responses are correct.
evolved from the same ancestor
Animals that possess homologous structures probably __________. have increased genetic diversity are headed for extinction are not related by chance had similar mutations independently in the past evolved from the same ancestor
several biologists had proposed that species might change over time, but none had suggested a convincing mechanism that might cause the change
At the time Charles Darwin sailed on HMS Beagle, __________. the idea of evolution was widely accepted because it could fit into the biblical story of creation the idea of evolution was widely accepted by scientists, but Darwin's great impact was to popularize it for the layperson the idea that animals and plants might change over time was absent from Western science several biologists had proposed that species might change over time, but none had suggested a convincing mechanism that might cause the change None of the listed responses is correct.
had been created by divine intervention a few thousand years before
At the time Darwin voyaged on the HMS Beagle, the popularly accepted theory in Western culture that explained the origin of Earth's plants and animals held that the various species __________. are all related to one another had been created by divine intervention a few thousand years before arose from a single species that had survived the biblical flood had evolved from now-extinct organisms arose continually from nonliving materials by spontaneous generation
Organisms within a population vary, and all populations produce more offspring than can be supported by the environment, resulting in competition for survival within the population.
Because he was well aware of the effect his theory of evolution would have on the public and on the Church of England, Darwin delayed publishing his work for several decades while he gathered additional evidence. After invoking selective breeding of domesticated species as evidence that groups of organisms are capable of change, he then proposed that natural populations can change as well. On which two lines of evidence did he base this proposal? Some individuals leave more descendants than other individuals, but the individuals in a population are essentially identical to each other. Organisms within a population vary, and all populations produce more offspring than can be supported by the environment, resulting in competition for survival within the population. Some individuals within a population have greater success in survival and reproduction than others, and favorable traits within a population will accumulate over generations. Organisms produce more offspring than can be supported by their environment, and adaptations to specific environments increase an organism's ability to survive and reproduce. Individuals within a population vary, yet island species around the world all appear to be related to each other.
the binomial classification system; thought that resemblances among different species reflected the pattern of their creation
Carolus Linnaeus is considered to be the founder of __________, and he __________. evolution; first proposed that acquired characteristics are inherited genetics; described the mechanism for descent with modification paleontology; believed in catastrophism uniformitarianism; believed the same geologic forces are operating today that occurred in the past the binomial classification system; thought that resemblances among different species reflected the pattern of their creation
proposed natural selection as the mechanism of evolution
Charles Darwin _____. was the first to realize that fossils are remains of ancient organisms proposed natural selection as the mechanism of evolution eagerly published his theory before it was well-developed was the first person to conclude that organisms evolve proposed that unused parts of the body deteriorate
descent with modification
Darwin originally defined evolution as __________. an individual's ability to adapt to its environment the passing of acquired characteristics to offspring descent with modification a way to classify organisms based on morphological similarities
natural selection
Darwin's explanation of how adaptations arise centered on __________. inheritance of acquired characteristics descent with modification artificial selection natural selection use and disuse
evolution
Descent with modification; the idea that living species are descendants of ancestral species that were different from the present-day ones; also defined more narrowly as the change in the genetic composition of a population from generation to generation.
All of the listed responses are correct.
During his voyage around the world, Darwin was inspired to think about evolution by __________. the works of others such as Lamarck fossils he collected studying adaptations of organisms to their environments the unique organisms he saw in the Galápagos Islands All of the listed responses are correct.
All of the listed responses are correct.
During periods of rapid environmental change, what may happen to a species that was well-suited to the former environment? Traits that were favorable in the original environment may be detrimental in the new environment. Individuals with particular traits that provide an advantage in the new environment will have higher reproductive success. The population may change so much in adapting to the new environment that it is considered a new species. All of the listed responses are correct. The species may go extinct.
convergent evolution
Even though rodents known as sugar gliders and flying squirrels are members of distinctly different groups of organisms and live on different continents, they possess similar characteristics. This is an example of __________. convergent evolution adaptation use and disuse acquired characteristics homology All of the listed responses are correct.
closely related organisms have more similar DNA and proteins than more distantly related organisms
Evidence from molecular biology supports the theory of evolution by demonstrating that __________. closely related organisms have similar stages of development homologous proteins have arisen independently in many different animal groups closely related animal species have similar geographic distributions closely related organisms have more similar DNA and proteins than more distantly related organisms None of the listed responses is correct.
organisms had adapted to new environments, giving rise to new species
From his observations of organisms in the Galapagos islands, Darwin reasoned that _____. all island species should be similar to each other the organisms in the Galapagos had been specially created to thrive in that environment organisms had adapted to new environments, giving rise to new species the shape of a bird's beak does not affect its ability to survive and reproduce none of the above
analogous
Having characteristics that are similar because of convergent evolution, not homology.
vestigial structures
Homologies that appear to have marginal, if any, importance to an organism are called __________. mutations adaptations vestigial structures homologous structures acquired characteristics
Darwin reasoned that the Earth must be very old and that slow, subtle processes could produce substantial biological changes.
How did Hutton and Lyell's ideas influence Charles Darwin's thinking? Darwin used Hutton and Lyell's ideas to develop the scala naturae. Darwin reasoned that the Earth must be very old and that slow, subtle processes could produce substantial biological changes. Darwin speculated that extinctions are common events during the course of time. None of the listed responses is correct. Darwin reasoned that the Earth must be very young and that sudden events could produce substantial biological changes. Darwin reasoned that organisms could pass acquired modifications to their offspring.
Some members of the bacteria population must have had a genetic variation that made them resistant to antibiotics, and these bacteria had greater reproductive success than sensitive individuals.
How did some strains of Staphylococcus aureus become resistant to antibiotic drugs? Patients did not take the drug as it was prescribed. Some members of the bacteria population must have had a genetic variation that made them resistant to antibiotics, and these bacteria had greater reproductive success than sensitive individuals. The bacterium mutated in response to the drug. The drug did not work in the way that the developers intended. None of the listed responses is correct.
Experiments in genetics show that traits acquired during an individual's lifetime are not inherited in the way proposed by Lamarck.
How does our understanding of genetics today refute Lamarck's principle of the inheritance of acquired characteristics? Parts of the body that are not used will deteriorate over time. Experiments in genetics show that traits acquired during an individual's lifetime are inherited in the way proposed by Lamarck. All of the listed responses are correct. All organisms are perfect and permanent. Experiments in genetics show that traits acquired during an individual's lifetime are not inherited in the way proposed by Lamarck. Parts of the body that are used extensively will become stronger and be passed to offspring.
natural selection can improve the match between an organism and its environment
In Darwin's view of descent with modification, __________. natural selection can improve the match between an organism and its environment environmental changes have no effect on the organisms living in that environment an organism's traits only affect its own survival individuals can evolve natural selection only operates when an organism needs to evolve
adaptation
Inherited characteristic of an organism that enhances its survival and reproduction in a specific environment.
strongly influenced Darwin's view of how living organisms could change over time
Lyell's principle of uniformitarianism __________. strongly influenced Darwin's view of how living organisms could change over time was rejected by Darwin in favor of catastrophism was similar to Lamarck's theory of inheritance of acquired characteristics was compatible with the idea of Earth being only a few thousand years old states that current geologic processes are very different from those that operated in the past
a change in an individual's DNA
Mutations are always __________. a change in an individual's DNA neutral good bad
homologous characteristics form a nested pattern
On an evolutionary tree, __________. homologous characteristics form a nested pattern the concept of descent with modification is not well-represented scientists are sure of the correct placement and relationships of all organisms organisms that are positioned close to each other are closely related
endemic
Organisms found only in specific places in the world are referred to as __________. tetrapods analogous endemic homologous introduced species convergent
Georges Cuvier
Paleontology, the study of fossils, was developed by __________. Georges Cuvier Aristotle Charles Darwin James Hutton Charles Lyell
endemic
Referring to a species that is confined to a specific geographic area.
homology
Similarity in characteristics resulting from a shared ancestry.
homologous structures
Structures in different species that are similar because of common ancestry.
Some members of the bacteria populations possessed some sort of genetic variation for antibiotic resistance that was selected for when the bacteria was exposed to the drugs.
The bacteria Staphylococcus aureus has developed resistance to some antibiotic drugs. How did this resistance come about? Genetic recombination of alleles during sexual reproduction in the bacteria produced antibiotic resistant genes. Some members of the bacteria populations possessed some sort of genetic variation for antibiotic resistance that was selected against when the bacteria was exposed to the drugs. Some members of the bacteria populations possessed some sort of genetic variation for antibiotic resistance that was selected for when the bacteria was exposed to the drugs. Some members of the bacteria populations acquired resistance genes by being exposed to the antibiotic. Some members of the bacteria populations mutated and developed resistance.
artificial selection
The breeding of plants and animals for particular traits by humans is called __________. sexual recombination paleontology natural selection artificial selection homology
convergent evolution
The evolution of similar features in independent evolutionary lineages.
Cuvier
The modern idea of extinction as a common occurrence in Earth's history was first proposed in the early 19th century writings of __________. Cuvier Lamarck Wallace Lyell Aristotle
Aristotle
The scala naturae, or scale of nature, is based on the ideas of __________. Lamarck Linnaeus Darwin Lyell Aristotle
paleontology
The scientific study of fossils.
biogeography
The scientific study of the past and present geographic distributions of species.
artificial selection
The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits.
pangaea
The supercontinent that formed near the end of the Paleozoic era, when plate movements brought all the landmasses of Earth together.
Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy.
The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data? Genes mutate faster in whales than in humans or bats. Humans and bats evolved by natural selection, and whales evolved by Lamarckian mechanisms. Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy. Whales are not properly classified as mammals. Forelimb evolution was adaptive in people and bats, but not in whales.
remnants of structures that were useful to an organism's ancestors, but which are now non-functional or show reduced function
Vestigial organs are __________. examples of anatomical imperfections such as the human knee remnants of structures that were useful to an organism's ancestors, but which are now non-functional or show reduced function evidence for Lamarck's theory of use and disuse one piece of evidence that does not support the theory of evolution homologies that can only be observed in embryos
They are often closely related to species from the nearest mainland or neighboring islands.
What did Darwin observe about species on islands? They are often closely related to species from similar ecological niches all over the world. They are often closely related to species from the nearest mainland or neighboring islands. Darwin only studied the Galápagos and, therefore, could not develop many insights about species on islands. They are rarely endemic. None of the above is correct.
The common ancestor of the lineages beginning there and to the right of it
What does each branch point on an evolutionary tree Convergent evolution A homologous characteristic shared by all groups to the right of the branch point An analogous characteristic shared by all groups to the right of the branch point The common ancestor of the lineages beginning there and to the right of it A homologous characteristic shared by all groups to the left of the branch point
Evolution is a broad model that is supported by many observations and much experimental evidence.
What does it mean to describe evolution as a scientific theory? Evolution is not observable. Evolution is narrow in scope and focuses only on very specific examples. Evolution does not explain how organisms have changed over time. Evolution is not testable. Evolution is a broad model that is supported by many observations and much experimental evidence.
Organisms have the capacity to overreproduce.
What insight did Darwin gain from reading Thomas Malthus's essay on human suffering? Natural selection should be capable of considerable modifications over hundreds of thousands of generations. Population size usually remains relatively stable. Favorable characteristics of a population accumulate over time. Organisms have the capacity to overreproduce. All of the listed responses are correct.
Organisms have the capacity to produce more offspring than the environment can support.
What insight did Darwin gain from reading Thomas Malthus's essay on human suffering? Natural selection should be capable of considerable modifications over hundreds of thousands of generations. Organisms have the capacity to produce more offspring than the environment can support. Favorable characteristics of a population accumulate over time. Population size usually remains relatively stable. All of the listed responses are correct.
If dark-colored rock pocket mice had a competitive advantage of 0.1%, it would take longer for 95% of the population to have dark fur.
When dark-colored fur gives mice a 1% competitive advantage and 1% of the population begins with dark fur, in about 1000 years, 95% of the population will have dark fur. Which of the following statements is true? If dark-colored mice had a competitive advantage of 10%, it would take longer for 95% of the population to have black fur. If dark-colored mice had a competitive advantage of 5%, it would take longer for 95% of the population to have black fur. If dark-colored rock pocket mice had a competitive advantage of 0.1%, it would take longer for 95% of the population to have dark fur. Dark-colored rock pocket mice, in this population, have fewer offspring than light-colored rock pocket mice.
many mosquitoes today are descendants of mosquitoes with insecticide-resistant characteristics
When they were first sold, aerosol insecticides were highly effective in killing flies and mosquitoes. Now, several decades later, a much smaller proportion of these insects die when sprayed. The reason fewer insects die when they are sprayed is that __________. mosquitoes that survive spraying develop an immunity to the insecticide the original spraying has caused a permanent mutation, giving the insects genetic resistance to the spray mosquitoes are deliberately adapting themselves to this man-made change in the environment many mosquitoes today are descendants of mosquitoes with insecticide-resistant characteristics None of the listed responses is correct.
Many basic characteristics are shared by all living things.
Which of the following is a key observation that must be explained in a unifying theory about life? Earth is very old. Evolution is based on descent with modification. All living things require oxygen to survive. Many basic characteristics are shared by all living things. Organisms are rarely well-suited to their environments.
He proposed natural selection as the mechanism of evolution.
Which of the following is a true statement about Charles Darwin? He proposed natural selection as the mechanism of evolution. He was the first to discover that living things can change, or evolve. He based his theory on the inheritance of acquired characteristics. He worked out the principles of population genetics. He was the first to conclude that Earth is billions of years old.
Dolphins and sharks have a similar streamlined body shape.
Which of the following is an example of convergent evolution? Dolphins and sharks have a similar streamlined body shape. Human embryos and fish embryos both have pharyngeal pouches. Blind cave fish possess remnants of eye structures under their scales. Cats and bats have similar skeletal configurations in their forelimbs. Both gymnosperms (cone-bearing plants) and angiosperms (flowering plants) produce seeds.
herbivory
Which of the following is an example of the process of evolution? the large number and diversity of species of marsupials in Australia the changes in organisms over time observed in the fossil record the existence of homologous traits such as the forelimbs of mammals herbivory the observed match between organisms and their environments
All of the listed responses are correct.
Which of the following is correct regarding natural selection? Natural selection is a process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than do individuals without those traits. If an environment changes, or if individuals move to a new environment, natural selection may result in adaptation to these new conditions, sometimes giving rise to new species. None of the listed responses is correct. Individuals do not evolve; populations do. All of the listed responses are correct. Over time, natural selection can increase the correspondence between organisms and their environments.
Poorly adapted individuals never produce offspring.
Which of the following is not an observation or inference on which natural selection is based? Only a fraction of an individual's offspring may survive. Species produce more offspring than the environment can support. There is heritable variation among individuals. Poorly adapted individuals never produce offspring. Individuals whose characteristics are best suited to the environment generally leave more offspring than those whose characteristics are less well suited.
Interactions between individuals and their environments cause individuals to evolve.
Which of the following is not an observation or inference that Darwin made while developing his theory of evolution? The unequal abilities of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations. Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than do other individuals. Interactions between individuals and their environments cause individuals to evolve. All species can produce more offspring than their environments can support, and many of these offspring fail to survive and reproduce. Members of a population often vary in their inherited traits.
Aristotle
Which of the following people developed the idea known as the scala naturae, or scale of nature? Aristotle Lyell Hutton Linnaeus Darwin Wallace
There is no selection for dark bellies by visual predators.
Why do dark-colored rock pocket mice on dark lava flows have white bellies? Mutations causing dark bellies do not occur. There is no selection for dark bellies by visual predators. White bellies are an important part of camouflage. There is a reproductive advantage to having a dark belly.