Verified Test Bank Chapter.5 Evolution & Human Variation 5e

Chapter 5: How Does the Evolutionary Study of Human Variation Undermine Notions of Biological Race?

Test Bank

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 01]

1) The subfield of evolutionary studies that devotes attention to short-term evolutionary changes is

Feedback: Microevolution refers to the more intimate, localized evolutionary changes that take place from one generation to the next within particular species of living organisms.
Page reference: What Is Microevolution?

a. macroevolution.

b. microevolution.

c. modern synthesis.

d. natural selection.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 02]

2) The subfield of evolutionary studies that focuses on long-term evolutionary changes is

Feedback: Macroevolution is the vast patterns of evolutionary change revealed by the fossil record.
Page reference: What Is Microevolution?

a. macroevolution.

b. microevolution.

c. modern synthesis.

d. natural selection.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 03]

3) The concept that defines a species as a reproductive community of populations (reproductively isolated from others) that occupies a specific niche in nature is the

Feedback: Neo-Darwinians defined a species as “a reproductive community of populations (reproductively isolated from others) that occupies a specific niche in nature” (Mayr 1982, 273). This definition, commonly referred to as the Biological Species Concept, has been useful to field biologists studying populations of living organisms. However, this definition of species has been less useful for scientists studying fossils.

Page reference: What Is A Species?

a. breeding group concept.

b. phylogenetic species concept.

c. phenetic fossil species concept.

d. biological species concept.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 04]

4) The concept that defines a species on the basis of a set of unique features (morphological or genetic) that distinguish its members from other, related species is called the

Feedback: Many taxonomists working with living primates prefer to use the Phylogenetic Species Concept, which identifies species on the basis of a set of unique features (morphological or genetic) that distinguish their members from other, related species, based on cladistic analysis.

Page reference: What Is A Species?

a. breeding group concept.

b. phylogenetic species concept.

c. phenetic fossil species concept.

d. biological species concept.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 05]

5) The concept that defines a fossil species based on the degrees of morphological difference that can be calculated between living species is called the

Feedback: Users of the Phenetic Fossil Species Concept first attempt to calculate the measurable morphological differences between living species. They then assume that similar degrees of morphological difference may also be used to distinguish species in the fossil record. Fleagle observes that this concept can be a useful way to sort fossils in a continuously changing lineage “in which the endpoints may be very different but individual samples overlap” (2013, 2).

Page reference: What Is A Species?

a. breeding group concept.

b. phylogenetic species concept.

c. phenetic fossil species concept.

d. biological species concept.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 06]

6) All of the genes in the bodies of all members of a given species or population make up a

Feedback: Gene pool refers to all the genes in the bodies of all members of a given species (or a population of a species).

Page reference: What Is A Species?

a. gene pool.

b. genotype.

c. gene frequency.

d. gene flow.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 07]

7) The field that focuses on the study of short-term evolutionary change in a given species is known as

Feedback: Population genetics is a field that uses statistical analysis to study short-term evolutionary change in large populations.

Page reference: What Is A Species?

a. genetics.

b. macrogenetics.

c. microgenetics.

d. population genetics.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 08]

8) Which of the following is used to describe alleles that come in a range of different forms?

Feedback: Population genetics is a field that uses statistical analysis to study short-term evolutionary change in large populations.
Page reference: What Is A Species?

a. Clines

b. Genetic variation

c. Gene frequency

d. Polymorphous

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 09]

9) The distribution of skin pigmentation from the poles to the equator forms a

Feedback: Cline refers to a pattern of gradually shifting frequency of a phenotypic trait from population to population across geographic space.

Page reference: What Is A Species?

a. cline.

b. chwartz.

c. kepllin.

d. koan.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 10]

10) The creation of a new allele for a gene when the chemistry of the DNA molecule to which it corresponds is suddenly altered is called

Feedback: Mutation are the creation of a new allele for a gene when the portion of the DNA molecule to which it corresponds is suddenly altered.
Page reference: What Is a Species?

a. gene flow.

b. genetic drift.

c. mutation.

d. plasticity.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 11]

11) Gene frequencies may be altered if a given population begins to interbreed with another population of the same species. This is known as

Feedback: Gene flow is the exchange of genes that occurs when a given population experiences a sudden expansion because of in-migration of outsiders from another population of the species.
Page reference: What Is a Species?

a. gene flow.

b. genetic drift.

c. mutation.

d. natural selection.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 12]

12) Random changes in gene frequencies from one generation to the next due to a sudden reduction in population size and resulting in the loss of particular alleles is known as

Feedback: Gene flow is the exchange of genes that occurs when a given population experiences a sudden expansion because of in-migration of outsiders from another population of the species.
Page reference: What Is a Species?

a. gene flow.

b. genetic drift.

c. mutation.

d. natural selection.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 13]

13) Today, many biologists and anthropologists agree that the most intense selection pressures our species faces come from

Feedback: Our species faces intense selection pressures from disease organisms that target our immune systems (Farmer 2003; Leslie and Little 2003). Evidence that microorganisms are a major predatory danger to humans comes from research on the connection between infectious diseases and polymorphic blood groups (i.e., blood groups that have two or more genetic variants within a population).

Page reference: What Is a Species?

a. the extinctions of other species.

b. global climate change.

c. disease organisms that target the immune system.

d. radiation from outer space.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 14]

14) The physiological flexibility that allows organisms to respond to environmental stresses, such as temperature change is called

Feedback: Phenotypic plasticity is physiological flexibility that allows organisms to respond to environmental stresses, such as temperature changes.

Page reference: What Is a Species?

a. adaptive conjuncture.

b. niche construction.

c. phenotypic plasticity.

d. acclimatization.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 15]

15) The mutual shaping of organisms and their environments is known as

Feedback: Adaptation refers to (1) The mutual shaping of organisms and their environments. (2) The shaping of useful features of an organism by natural selection for the function they now perform.

Page reference: What Is a Species?

a. acclimatization.

b. adaptation.

c. plasticity.

d. pleiotropy.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 16]

16) The process by which one species gradually transforms itself into a new species over time is called

Feedback: Phyletic gradualism is a theory arguing that one species gradually transforms itself into a new species over time, yet the actual boundary between species can never be detected and can only be drawn arbitrarily.

Page reference: What Is a Species?

a. cladogenesis.

b. phenotypic transformation.

c. phyletic gradualism.

d. punctuated equilibrium.

Type: multiple choice question

Title: [Knowledge of Key Terms and Concepts: Chapter 05 Question 17]

17) A change in the way the body functions in result to physical stress is called

Feedback: Acclimatization is a change in the way the body functions in response to physical stress.
Page reference: Can We Predict the Future of Human Evolution?

a. acclimatization.

b. adaptation.

c. plasticity.

d. pleiotropy.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 18]

18) The concept of race has not disappeared from contemporary discussions of human variation, and in recent years, discussions that connect race and biology have been revived, referred to as

Feedback: The concept of race has not disappeared from contemporary discussions of human variation. And so we look at some of the factors that have, in recent years, revived discussions that connect race and biology—the so-called molecularization of race. This revival followed the sequencing of the human genome, and was encouraged by the connections some geneticists, physicians and others have tried to make between genes, race, and disease. We will show how anthropologists have responded to this revival by emphasizing processes of biosocial or biocultural becoming over the course of human development, showing show “how race becomes biology through the embodiment of social inequality” (Gravlee 2013, 22).
Page reference: What Is Microevolution?

a. natural selection.

b. macroevolution.

c. molecularization of race.

d. microevolution.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 19]

19) Species are normally subdivided into populations that are more or less scattered, that may be separated at one time, but may merge together again, and successfully reproduce, at a later time. This process is called

Feedback: Evolutionary biologists normally subdivide species into populations that are more or less scattered, although the separation is not complete. That is, populations of the same species (or individual members of those populations) may be separated at one time, but may merge together again, and successfully reproduce, at a later time. Evolutionary theorists Ian Tattersall and Rob DeSalle describe this process of species differentiation and reintegration as reticulation (Tattersall and DeSalle 2011, 50).

Page reference: What Is A Species?

a. reticulation.

b. speciation.

c. phylogenesis.

d. ontogenesis.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 20]

20) “Population thinking” is central to the evolutionary thinking of

Feedback: Darwinian population thinking requires biologists to recognize the distinctiveness of each individual organism that belongs to a particular population of a given species. It is variation among individual organisms in particular populations, in particular environmental circumstances, that engenders the Darwinian struggle for existence. To follow arguments made by evolutionary biologists, therefore, these three nesting concepts—species made up of populations made up of organisms—must be kept distinct from one another. It is also important to remember that even if individual organisms from populations of different species occasionally mate with one another, such matings do not necessarily dissolve the species boundary.

Page reference: What Is A Species?

a. Linnaeus.

b. Lamarck.

c. Cuvier.

d. Darwin.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 21]

21) According to Nadia Abu El-Haj, some biomedical researchers in the United States use racial groups as surrogates for individuals who consider themselves to be members of such groups. Why?

Feedback: As Abu El-Haj explains, some biomedical researchers in the United States use “racial” groups as surrogates for individuals who consider themselves members of such groups. The thinking is that if a genetic disease marker shows up in the genomes of some people said to be members of a particular “race,” then this may be an indication that other people classified in the same “race” might also be at risk for the disease.

Page reference: What Is a Species?

a. If a disease marker shows up in the genomes of some people who are supposed to be in the racial group, then others in the same racial group may be at risk for the disease.

b. People who belong to the same race will have the same basic genetic information and therefore will need to be treated for the same diseases.

c. The biomedical researchers make the mistake of thinking that races exist; therefore, they are making a mistake in their research.

d. They are looking for a way to demonstrate, once and for all, that biological race is real.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 22]

22) Clarence Gravlee and his colleagues carried out research in Puerto Rico, attempting to explain why darker skin pigmentation was associated with higher blood pressure. They found that Puerto Ricans with darker skins and higher socioeconomic status actually experienced higher blood pressure than other Puerto Ricans. How did they interpret this finding?

Feedback: This “biocultural” (or “biosocial”) approach revealed that Puerto Ricans with darker skins and higher socioeconomic status actually experienced higher blood pressure than other Puerto Ricans. This was interpreted as resulting from the fact that such individuals were likely to experience more intense racism as their social status increased, thereby producing increasingly frustrating social interactions that contributed to higher blood pressure (Gravlee 2013, 38).

Page reference: What Is a Species?

a. They realized that their ways of measuring skin color were inaccurate.

b. Individuals with darker skins and higher socioeconomic status were likely to experience more intense racism, which contributed to higher blood pressure.

c. They realized that their ways of measuring blood pressure were inaccurate.

d. Higher blood pressure does not actually correlate with skin color.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 23]

23) A well-known example of a balanced polymorphism is

Feedback: When individuals inherit the HbS allele from both parents, they develop sickle-cell anemia. Because the HbS allele seems to be harmful, we would expect it to be eliminated through natural selection. But in some populations of the world, it has a frequency of up to 20% in the gene pool. Geneticists might have concluded that this high frequency was the result of genetic drift if it were not for the fact that the areas with a high frequency of HbS are also areas where the mosquito-borne malaria parasite is common. There is, in fact, a connection. People exposed to malaria have a better chance of resisting the parasite if their hemoglobin genotype is HbA/HbS rather than the normal HbA/HbA. This is an example of what geneticists call a “balanced polymorphism,” in which the heterozygous genotype is fitter than either of the homozygous genotypes.

Page reference: What Is a Species?

a. acclimatization response.

b. body shape in cold climates.

c. red hair color.

d. sickle-cell anemia.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 24]

24) A situation in which the heterozygous genotype is fitter than either of the homozygous genotypes is called

Feedback: A “balanced polymorphism” occurs when the heterozygous genotype is fitter than either of the homozygous genotypes.

Page reference: What Is a Species?

a. a balanced polymorphism.

b. Bregmann’s Rule.

c. hemoglobin A.

d. a natural selection adjustment.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 25]

25) When variations in skin color of indigenous populations of the world are plotted on a map,

Feedback: If you were to walk from Stockholm, Sweden, to Cape Town, South Africa (or from Singapore to Beijing, China), you would perceive gradual changes in average skin color as you moved from north to south (or vice versa). Evolutionary biologists explain this pattern as a consequence of natural selection: individuals in tropical populations with darker skin pigmentation had a selective advantage in equatorial habitats over individuals with light pigmentation.

Page reference: What Is a Species?

a. the populations with the darkest pigmentation live furthest from the equator.

b. the populations with the darkest pigmentation live closest to the equator.

c. skin color is randomly distributed throughout the world.

d. indigenous populations have relatively consistent skin color.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 26]

26) Much recent research has demonstrated that IQ scores are

Feedback: When African Americans and European Americans are matched in terms of these factors, the differences in average IQ scores disappear (Molnar 1992). The results of these studies are not new. On the contrary, studies like these demonstrate repeatedly that IQ scores are not phenotypic traits uniquely determined by genes but that they are powerfully affected by a range of environmental factors over the course of the human life cycle.

Page reference: What Is a Species?

a. based on the test-taker’s genotype.

b. determined about 60 percent by genes and about 40 percent by the environment.

c. due to random factors such as temperature, noise, or mood, in the test-taking situation.

d. shaped by a range of environmental factors.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 27]

27) Recent research shows that when African Americans and European Americans are matched in terms of social class and educational background, the differences in average IQ scores

Feedback: When African Americans and European Americans are matched in terms of these factors, the differences in average IQ scores disappear (Molnar 1992).

Page reference: What Is a Species?

a. do not change.

b. disappear.

c. increase by 12 points.

d. vary inversely.

Type: multiple choice question

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 28]

28) When scholars use mathematical formulas to predict outcomes of particular kinds of human interactions under different hypothesized conditions, they are using what is (are) called

Feedback: Formal models are mathematical formulas to predict outcomes of particular kinds of human interactions under different hypothesized conditions.

Page reference: Can We Predict the Future of Human Evolution?

a. sociobiology.

b. scientific methods.

c. formal models.

d. fieldwork.

Type: true-false

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 29]

29) Denial of the existence of biological race is NOT to deny the existence of human biological or genetic diversity.

Feedback: The concept of race has not disappeared from contemporary discussions of human variation. And so we look at some of the factors that have, in recent years, revived discussions that connect race and biology—the so-called molecularization of race. This revival followed the sequencing of the human genome, and was encouraged by the connections some geneticists, physicians and others have tried to make between genes, race, and disease. We will show how anthropologists have responded to this revival by emphasizing processes of biosocial or biocultural becoming over the course of human development, showing show “how race becomes biology through the embodiment of social inequality” (Gravlee 2013, 22).
Page reference: What Is A Species?

a. True

b. False

Type: true-false

Title: [Comprehension of Fundamental Concepts: Chapter 05 Question 30]

30) When Clarence Gravlee and his colleagues carried out research on high blood pressure (or hypertension) in Puerto Rico, they found out that Puerto Ricans with darker skins and higher socioeconomic status experienced higher blood pressure than other Puerto Ricans.

Feedback: Gravlee and his colleagues used this approach to carry out research in Puerto Rico, attempting to explain why darker skin pigmentation was associated with higher blood pressure. They discovered that skin color had two dimensions that needed to be distinguished: “the phenotype of skin pigmentation and the cultural significance of skin color as a criterion of social status” (Gravlee 2013, 38). Measurement of skin pigmentation was carried out using the method of reflectance spectrometry, which reliably estimates the concentration of melanin in the skin.

Page reference: What Is a Species?

a. True

b. False

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 31]

31) Which of the following correctly describes the nesting of the concepts biologists use to organize their understanding of the living world?

Feedback: To follow arguments made by evolutionary biologists, therefore, these three nesting concepts—species made up of populations made up of organisms—must be kept distinct from one another. It is also important to remember that even if individual organisms from populations of different species occasionally mate with one another, such matings do not necessarily dissolve the species boundary.

Page reference: What Is A Species?

a. Organisms made up of populations made up of species

b. Species made up of populations made up of organisms

c. Populations made up of organisms made up of species

d. Species made up of genera made up of phyla

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 32]

32) Which of the following statements about the concept of “species” is correct?

Feedback: Species is a distinct segment of an evolutionary lineage. Different biologists, working with living and fossil organisms, have devised different criteria to identify boundaries between species.

Page reference: What Is A Species?

a. The biological species concept is used by all biologists, whether working with living or fossil organisms.

b. The phylogenetic species concept is used by all biologists, whether working with living or fossil organisms.

c. The phenetic species concept is used by all biologists, whether working with living or fossil organisms.

d. Different biologists, working with living and fossil organisms, have devised different criteria to identify boundaries between species.

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 33]

33) According to the text, if humanity cannot be divided into a series of genetically distinct units, then

Feedback: Human population genetics has shown that different human populations from all over the world share basically the same range of genotypic variation, no matter how different from one another they may appear phenotypically. These findings reinforce the claims of biological anthropologists that the concept of “race” is biologically meaningless: different phenotypic traits do not in fact cluster together in populations, as the biological race concept assumes. Rather, the clinal distribution of any individual phenotypic trait can be traced across geographical space, from population to population, as its frequency increases or decreases.

Page reference: What Is A Species?

a. the concept of race is biologically meaningless.

b. human races are based on very specific genetic variations.

c. microraces are the only biological possibility.

d. the concept of race must be revised.

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 34]

34) Following the completion of the Human Genome Project, a new race concept seems to be developing, based on the classification of

Feedback: Perhaps no more complicated set of questions has been raised about race in the twenty-first century than those that have emerged following the completion of the Human Genome Project (HGP) in 2003. The goals of the project were as follows: to identify all the approximately 20,000–25,000 genes in human DNA; to determine the sequences of the 3 billion chemical base pairs that make up human DNA; to store this information in databases; to improve tools for data analysis; to transfer related technologies to the private sector; and to address the ethical, legal, and social issues that may arise from the project.
Page reference: What Is a Species?

a. diseases.

b. genotypes.

c. phenotypes.

d. cells.

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 35]

35) Controversies such as the one involving BiDil are best understood as

Feedback: The current situation is perplexing, to say the least: such notions as race and “genetics” and “biology” are still with us, but their meanings appear to have changed, producing consequences that seem to be both positive and negative. Some observers suspect that this kind of research will only give the older racial classifications a new lease on life (see In Their Own Words, page 153). John Hartigan (2013) argues, however, that although biomedical research of this kind “seems to affirm that ‘biological differences’ are a more powerful explanation for health disparities than are social factors,” the situation is better understood as “the outcome of various ways in which people struggle to contend with the significance of race in multiple social and biological registers simultaneously, often in contradictory manners.”

Page reference: What Is a Species?

a. attempts to give old racial classifications a new lease on life.

b. evidence that contemporary biomedical research produces only negative consequences.

c. demonstrations that biological differences are a more powerful explanation for health disparities than are social factors.

d. the outcome of various ways in which people struggle to contend with the significance of race in multiple social and biological registers simultaneously, often in contradictory manners.

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 36]

36) Anthropologist Clarence Gravlee and his colleagues concluded their study on high blood pressure in Puerto Rico by arguing that

Feedback: Biocultural or biosocial approaches like that of Gravlee and his colleagues demonstrate, in the words of Greg Downey and Daniel Lende, how “social differences can become biology because they shape the emerging nervous system” (2012, 31). As Downey and Lende explain, “the predominant reason that culture becomes embodied . . . is that neuroanatomy inherently makes experience material” (2012, 37). Ultimately, they conclude, “The material environment, both natural and artificial, provides structure and information to the growing organism while being incorporated with its inherited biological legacy” (2012, 44).

Page reference: What Is a Species?

a. taking culture seriously may both clarify the consequences of social inequalities and empower future genetic association studies.

b. taking culture into account adds nothing to our understanding of the connection between race and health.

c. culture explains everything about why some groups in Puerto Rico experience higher blood pressure than others.

d. skin color explains everything about why some groups in Puerto Rico experience higher blood pressure than others.

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 37]

37) Which of the following is NOT one of the four evolutionary processes?

Feedback: Phenotypic plasticity is physiological flexibility that allows organisms to respond to environmental stresses, such as temperature changes.

Page reference: What Is a Species?

a. Gene flow

b. Genetic drift

c. Mutation

d. Plasticity

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 38]

38) Assume that in a small population, 15 percent of the people are blue-eyed and have brown hair. Assume further that within this population, there is an adventurous group that wishes to explore the region and settle down in new territory. Of this adventurous group, 87 percent are blue-eyed and have brown hair. When they leave, the gene frequencies in the remaining population will change for blue-eyes and brown hair in the next generation. This is an example of

Feedback: Genetic drift refers to random changes in gene frequencies from one generation to the next caused by a sudden reduction in population size as a result of disaster, disease, or the out-migration of a small subgroup from a larger population.

Page reference: What Is a Species?

a. gene flow.

b. genetic drift.

c. mutation.

d. natural selection.

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 39]

39) When human beings move into an area that seems too cold for them, they can wear clothing, build shelters, or cluster around a fire. These activities can be called

Feedback: Adaptation refers to (1) The mutual shaping of organisms and their environments. (2) The shaping of useful features of an organism by natural selection for the function they now perform.

Page reference: What Is a Species?

a. adaptation.

b. environmental stress.

c. plasticity.

d. pleiotropy.

Type: multiple choice question

Title: [Application of Concepts: Chapter 05 Question 40]

40) Which of the following is an example of acclimatization?

Feedback: Changes called “developmental acclimatization” are a consequence of human phenotypic plasticity and occur when the human body is challenged by a low level of oxygen in the environment. Studies have shown that individuals who were not born in such an environment increased in chest dimensions and lung capacity the longer they lived in such an environment and the younger they were when they moved there (Greska 1990).

Page reference: What Is a Species?

a. Overheating

b. Increased lung capacity in people raised at high altitudes

c. Increased male baldness in northern climates

d. Decreased sexual dimorphism

Type: true-false

Title: [Application of Concepts: Chapter 05 Question 41]

41) Variations in human skin color protect against ultraviolet radiation and impede the destruction of folic acid.

Feedback: Exposure of human skin to solar radiation has complex and contradictory consequences. Too much sunlight produces sunburn, and UVB destroys a B vitamin, folic acid, which is a crucial factor in healthy cell division. At the same time, solar radiation also has positive consequences: UVA stimulates the synthesis of vitamin D in human skin. Vitamin D is crucial for healthy bone development and other cellular processes.

Page reference: What Is a Species?

a. True

b. False

Type: true-false

Title: [Application of Concepts: Chapter 05 Question 42]

42) Cultural practices have not shaped the levels of pigmentation in human populations.

Feedback: Jablonski (2004) concludes that “the longer wavelengths of UVR . . . have been the most important agents of natural selection in connection with the evolution of skin pigmentation” (604). At the same time, because people have always migrated, different populations vary in the numbers of generations exposed to the selective pressures of any single regime of solar radiation. Human cultural practices (wearing clothes, using sun block, staying indoors) have shaped the levels of pigmentation and levels of vitamin D production in particular individuals or populations. Gene flow following the interbreeding of human populations with different selective histories would further complicate the relationship between the skin colors of their offspring and selection pressures imposed by local levels of solar radiation.

Page reference: What Is a Species?

a. True

b. False

Type: essay/short answer question

Title: [Application of Concepts: Chapter 05 Question 43]

43) Describe what it means to say that populations form a reproductive community. Use three examples from the text in your response.

Feedback: Neo-Darwinians defined a species as “a reproductive community of populations (reproductively isolated from others) that occupies a specific niche in nature” (Mayr 1982, 273). This definition, commonly referred to as the Biological Species Concept, has been useful to field biologists studying populations of living organisms. However, this definition of species has been less useful for scientists studying fossils. In fact, Fleagle notes that the Biological Species Concept has even been losing favor among field biologists because “as more and more ‘species’ have been sampled genetically, it has become clear that hybridization between presumed species has been very common in primate evolution” (Fleagle 2013, 1; see also Stringer 2012, 34).

Page reference: What Is Microevolution?

Type: essay/short answer question

Title: [Application of Concepts: Chapter 05 Question 44]

44) Using examples from the text, explain the difference between short-term acclimatization and developmental acclimatization.

Feedback: The shivering response in humans illustrates adaptation to the brief timescale of minute-to-minute fluctuations in the environment, a response in human beings sometimes called “short-term acclimatization.” Human beings are warm-blooded organisms who need to maintain a constant internal body temperature to function properly. Other forms of acclimatization take shape over more intermediate timescales. Such adaptations emerge over the course of many months or years, as human phenotypic plasticity is shaped by inputs from the particular environments within which individuals develop. That is, physiological or morphological changes resulting from developmental plasticity are not a consequence of genetic variation. Put another way, “developmental plasticity allows one genotype to give rise to multiple phenotypes in response to variation in the environment in which an organism develops” (Thayer and Non 2015, 728).

Page reference: What Is a Species?

Type: essay/short answer question

Title: [Application of Concepts: Chapter 05 Question 45]

45) Discuss the role randomness plays in evolution using examples.

Feedback: Most genetic variation results from mixing already existing alleles into new combinations. This variation is the natural result of chromosomal recombination in sexually reproducing species. However, gene frequencies can be drastically altered if a given population experiences a sudden expansion resulting from the in-migration of outsiders from another population of the species, which is called gene flow. A population that is unaffected by mutation or gene flow can still undergo genetic drift—random changes in gene frequencies from one generation to the next. Genetic drift may have little effect on the gene frequencies of large, stable populations, but it can have a dramatic impact on populations that are suddenly reduced in size by disease or disaster (the bottleneck effect) or on small subgroups that establish themselves apart from a larger population (the founder effect). Both of these effects accidentally eliminate large numbers of alleles.

Page reference: What Is a Species?

Type: essay/short answer question

Title: [Analysis and Synthesis: Chapter 05 Question 46]

46) Discuss the interaction of human cultural practices and biological selection pressures operating on human populations with regard to the sickle-cell genotype.

Feedback: The transition from a phenotypic to a genotypic view of race came about, she says, as a consequence of changing historical understandings of sickle-cell disease in the United States. In the first part of the twentieth century, sickle-cell anemia was identified as a disease of “black” people—of African Americans. But later, as we will shortly discuss, research in population genetics traced its cause to molecular genes: the presence of an abnormal “sickling” hemoglobin allele at a particular locus on a chromosome. “At the meeting point between these two definitions of the disease . . . the commitment to race as a molecular attribute took form,” leading over time to “the correlation of disease risk and racial difference” (Abu El-Haj 2007, 287).

Page reference: What Is a Species?

Type: essay/short answer question

Title: [Analysis and Synthesis: Chapter 05 Question 47]

47) Why do anthropologists reject the idea of biological races?

Feedback: We also show how microevolutionary work of this kind demonstrated that different phenotypic traits did not cluster in the ways predicted by the biological race concept. Instead, individual traits showed gradually shifting frequencies from population to population across geographic space—patterns called clines. When clinal maps for different traits were compared, it became instantly obvious that they did not cluster in overlapping patterns as the biological race concept had presumed. We review new findings that stress the openness of developing organisms to environmental inputs that are enlarging the way the concept of adaptation can be understood.

Page reference: What Is a Species?

Type: essay/short answer question

Title: [Analysis and Synthesis: Chapter 05 Question 48]

48) What are the major differences between the phyletic gradualism and punctuated equilibria approaches to interpreting evolution?

Feedback: Phyletic gradualism is a theory arguing that one species gradually transforms itself into a new species over time, yet the actual boundary between species can never be detected and can only be drawn arbitrarily. Punctuated equilibrium is a theory claiming that most of evolutionary history has been characterized by relatively stable species coexisting in an equilibrium that is occasionally punctuated by sudden bursts of speciation, when extinctions are widespread and many new species appear.

Page reference: What Is a Species?