21. Evolution

Introduction to Evolution and Natural Selection

21. Evolution

Introduction to Evolution and Natural Selection

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04:58

Evolution and Natural Selection

Introduction to Evolution and Natual Selection Example 1

Typological vs. Population Thinking

Introduction to Evolution and Natual Selection Example 2

Ladder vs. Tree Thinking

Introduction to Evolution and Natual Selection Example 3

Introduction to Evolution and Natual Selection Example 4

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Why do humans have a third eyelid? - Dorsa Amir

04:36

Why do humans have a third eyelid? - Dorsa Amir

Evolutionary Structures; Homologous, Analogous, and Vestigial

Descent With Modification

Vestigial Structures | What are Vestigial Structures?

Convergent Evolution in a Nutshell

Convergent and Divergent Evolution by Natural Selection

Convergent vs Divergent Evolution

Baylor Tutoring Center

Convergent vs Divergent Evolution

Convergent Evolution vs Divergent Evolution | Shared Traits Explained

Darwinian Evolution and Fitness

Natural Selection vs Artificial Selection | Mechanisms of Evolution

What is Natural Selection?

Descent with Modification

Darwin and Natural Selection: Crash Course History of Science #22

Descent With Modification

Charles Darwin's Idea: Descent With Modification

Professor Dave Explains

Fitness, Adaptation, and Artificial Selection

Convergent and Divergent Evolution

Vestigial Traits and Evolutionary Misconceptions

HHMI BioInteractive: The Making of the Fittest: Natural Selection in Humans

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Practice this topic

Multiple Choice

Darwin originally defined evolution as __________.

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Multiple Choice

Which of the following is a key observation that must be explained in a unifying theory about life?

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Multiple Choice

The scala naturae, or scale of nature, is based on the ideas of __________.

At the time Darwin voyaged on HMS Beagle, the popularly accepted theory in Western culture that explained the origin of Earth's plants and animals held that the various species __________.

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Multiple Choice

Carolus Linnaeus is considered to be the founder of __________, and he __________.

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Multiple Choice

The modern idea of extinction as a common occurrence in Earth's history was first proposed in the early-19th-century writings of __________.

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Multiple Choice

Lyell's principle of uniformitarianism __________.

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Multiple Choice

Which of the following is a true statement about Charles Darwin?

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Multiple Choice

At the time Charles Darwin sailed on HMS Beagle, __________.

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Multiple Choice

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?

During his voyage around the world, Darwin was inspired to think about evolution by __________.

In Darwin's view of descent with modification, __________.

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Multiple Choice

What insight did Darwin gain from reading Thomas Malthus's essay on human suffering?

The breeding of plants and animals for particular traits by humans is called __________.

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Multiple Choice

The smallest unit that can evolve is a(n) __________.

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Multiple Choice

During periods of rapid environmental change, what may happen to a species that was well suited to the former environment?

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Multiple Choice

According to the theory of evolution, anatomical and molecular homologies should __________.

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Multiple Choice

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 __________.

To describe evolution as a "scientific theory" means that __________.

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Multiple Choice

What did Darwin observe about species on islands?

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Multiple Choice

Evidence from molecular biology supports the theory of evolution by demonstrating that __________.

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Multiple Choice

All known organisms translate genetic information to produce protein molecules via the same genetic code. This finding strongly supports the hypothesis that __________.

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Multiple Choice

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?

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Multiple Choice

How did some strains of Staphylococcus aureus become resistant to antibiotic drugs?

Animals that possess homologous structures probably __________.

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Multiple Choice

Vestigial organs are __________.

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Multiple Choice

Which of the following is an example of convergent evolution?

On an evolutionary tree, __________.

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Textbook Question

What observations did Darwin make on the Galápagos Islands that helped convince him that evolution occurs? a. the existence of animals that did not fit into Linnaeus's classification system; b. the similarities and differences among cacti and tortoises on the different islands; c. the presence of species he had seen on other tropical islands far from the Galápagos; d. the radioactive age of the rocks of the islands; e. fossils of human ancestors

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Textbook Question

Summarize the key points of Darwin's theory of descent with modification, including his proposed mechanism of evolution.

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Textbook Question

What types of drugs have helped reduce the death rate due to tuberculosis infection, and why have they become less effective more recently?

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Textbook Question

Define artificial selection, and compare and contrast it with natural selection.

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Textbook Question

Complete this concept map describing potential causes of evolutionary change within populations. a. b. c. d. e. f. g.

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Textbook Question

Which of the following observations is not part of the theory of natural selection? a. Populations of organisms have more offspring than will survive; b. There is variation among individuals in a population; c. Modern organisms are unrelated; d. Traits can be passed on from parent to offspring; e. Some variants in a population have a higher probability of survival and reproduction than other variants do.

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Textbook Question

Traits that are derived from a common ancestor, like the bones of human arms and bird wings, are said to be .

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Textbook Question

Which of the following did not influence Darwin as he synthesized the theory of evolution by natural selection? a. examples of artificial selection that produce large and relatively rapid changes in domesticated species b. Lyell's Principles of Geology, on gradual geologic changes c. comparisons of fossils with living organisms d. Mendel's paper describing the laws of inheritance

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Textbook Question

Natural selection is sometimes described as 'survival of the fittest.' Which of the following best measures an organism's fitness? a. how many fertile offspring it produces b. how strong it is when pitted against others of its species c. its ability to withstand environmental extremes d. how much food it is able to make or obtain

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Textbook Question

The best definition of evolutionary fitness is . a. physical health; b. the ability to attract members of the opposite sex; c. the ability to adapt to the environment; d. survival and reproduction relative to other members of the population e. overall strength

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Textbook Question

The theory of common descent states that all modern organisms . a. can change in response to environmental change; b. descended from a single common ancestor; c. descended from one of many ancestors that originally arose on Earth; d. have not evolved; e. can be arranged in a hierarchy from 'least evolved' to 'most evolved'

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Textbook Question

Explain the logic behind the claim that the nuclear envelope is a synapomorphy that defines eukaryotes as a monophyletic group.

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Textbook Question

An adaptation is a trait of an organism that increases . a. its fitness; b. its ability to survive and replicate; c. in frequency in a population over many generations; d. A and B are correct; e. A, B, and C are correct

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Textbook Question

The DNA sequence for the same gene found in several species of mammals . a. is identical among all species; b. is equally different between all pairs of mammal species; c. is more similar between closely related species than between distantly related species; d. provides evidence for the hypothesis of common descent; e. more than one of the above is correct

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Textbook Question

Marsupial mammals give birth to young that complete their development in a pouch on the mother's abdomen. All the native mammals of Australia are marsupials, while these types of mammals are absent or uncommon on other continents. This observation is an example of a.developmental evidence for evolution; b. biogeographic evidence for evolution; c. genetic evidence for evolution; d. fossil evidence for evolution; e. not useful evidence for evolution

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Textbook Question

A swim bladder is a gas-filled sac that helps fish maintain buoyancy. Evidence indicates that early fish gulped air into primitive lungs, helping them survive in stagnant waters. The evolution of the swim bladder from lungs of an ancestral fish is an example of a. an evolutionary trend. b. paedomorphosis. c. the gradual refinement of a structure with the same function. d. exaptation.

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Textbook Question

Since the modern synthesis, the technical definition of evolution is a change in in a over the course of generations. a. traits, species; b, allele frequency, population; c. natural selection, natural environment; d. adaptations, single organism; e. fitness, population

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Textbook Question

Even though marsupial mammals give birth to live young, an eggshell forms briefly early in their development. This is evidence that a.marsupials share a common ancestor with some egg-laying species; b. marsupials are not really mammals; c. all animals arose from a common ancestor; d. marsupial mammals were separately created by God; e. the fossil record of marsupial mammals is incorrect

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Textbook Question

Within a few weeks of treatment with the drug 3TC, a patient's HIV population consists entirely of 3TC-resistant viruses. How can this result best be explained? a. HIV can change its surface proteins and resist vaccines. b. The patient must have become reinfected with a resistant virus. c. A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency. d. HIV began making drug-resistant versions of its enzymes in response to the drug.

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Textbook Question

Explain why the overprescription of antibiotics by doctors, or the overuse of everyday soaps containing antibiotics, can be a health risk.

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Textbook Question

Similarity in skin color among different human populations appears to be primarily the result of . a. natural selection; b. convergent evolution; c. which biological race they belong to; d. A and B are correct; e. A, B, and C are correct

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Textbook Question

A species of crayfish that lives in caves produces eyestalks like its above-ground relatives, but has no eyes. Eyestalks in cave-dwelling crayfish are thus . a. an evolutionary error; b. a dominant mutation; c. biogeographical evidence of evolution; d. a vestigial trait; e. evidence that evolutionary theory may be incorrect

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Textbook Question

Which of the following taxonomic levels contains organisms that share the most recent common ancestor? a. family; b. order; c. phylum; d. genus; e. class

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Textbook Question

Most mice living on the mainland of Florida are brown, but the mice that live on the sand dunes of the barrier islands have white fur. The differences in color are heritable, determined by genes such as MC1R. It is intuitive that the light color of beach-dwelling mice is an adaptation for blending into their environment—and thus evading predators. Compare how evolution by inheritance of acquired characters and the theory of evolution by natural selection would explain the observation of white mice living primarily on light soil and brown mice living primarily on dark soil.

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Textbook Question

Most mice living on the mainland of Florida are brown, but the mice that live on the sand dunes of the barrier islands have white fur. The differences in color are heritable, determined by genes such as MC1R. It is intuitive that the light color of beach-dwelling mice is an adaptation for blending into their environment—and thus evading predators. What is an evolutionary adaptation? a. a trait that improves the fitness of its bearer, compared with individuals without the trait b. a trait that changes in response to environmental influences within the individual's lifetime c. the ability of an individual to adjust to its environment d. a trait that an individual wants so that it can survive

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Textbook Question

How can the Darwinian concept of descent with modification explain the evolution of such complex structures as an eye?

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Textbook Question

Apply Darwin's four postulates to a population of mice living on sand dunes in coastal Florida.

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Textbook Question

A team led by evolutionary biologist Hopi Hoekstra set out to test the hypothesis that predators are an agent of natural selection on mouse color. They made 250 plasticine models of mice that were alike in every way except that half were painted white and half were painted brown. Suggest one advantage and one disadvantage of using model mice instead of real mice in this experiment.

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Textbook Question

A population of snails is preyed on by birds that break the snails open on rocks, eat the soft bodies, and leave the shells. The snails occur in both striped and unstriped forms. In one area, researchers counted both live snails and broken shells. Their data are summarized below: Which snail form seems better adapted to this environment? Why? Predict how the frequencies of striped and unstriped snails might change in the future.

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Textbook Question

The researchers placed white and brown mouse models both in abandoned fields on the mainland (dark soil) and on sand dunes on the islands (light soil) and then measured the percentage of models that were attacked by predators. What is the take-home message of the data? Do the data support or reject the hypothesis that mouse color is adaptive?

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Multiple Choice

Which organism will have the highest fitness?

Which statement would be supported by the concept of common descent?

What is one reason population thinking is so important in biology?

Dog breeds are defined by denoting breed standards, a list of agreed-upon traits that individuals of that breed should possess (such as size, coat, coloring, temperament, etc.). Dog shows rank dogs based on their adherence to these breed standards. Based on this information, which statement about dog breeds below is correct?

True or False: if false, choose the answer that best corrects the statement.

In tree thinking, species are organized from low complexity to high complexity.

The Latin term Scala Naturae reflects which argument?

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