Biology: Life on Earth (11th Edition)
11th Edition
ISBN: 9780134168296
Author: Gerald Audesirk, Teresa Audesirk, Bruce E. Byers
Publisher: PEARSON
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Textbook Question
Chapter 16, Problem 1AC
In North America, the average height of adult humans has been increasing steadily for decades. Is directional selection occurring? What data would justify your answer?
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Chapter 16 Solutions
Biology: Life on Earth (11th Edition)
Ch. 16 - The alleles responsible for antibiotic resistance...Ch. 16 - Stabilizing selection on a trait tends to a. make...Ch. 16 - An adaptation is any trait that arises from a...Ch. 16 - 4. Which of the following statements about...Ch. 16 - 5. Genetic drift occurs
a. when different...Ch. 16 - The ________ provides a simple mathematical model...Ch. 16 - 2. Different versions of the same gene are called...Ch. 16 - An organism's ________ refers to the specific...Ch. 16 - 4. A random form of evolution is called _________....Ch. 16 - Competition is most intense between members of...
Ch. 16 - 6. The evolutionary fitness of an organism is...Ch. 16 - 1. What is a gene pool? How would you determine...Ch. 16 - 2. Define equilibrium population. Outline the...Ch. 16 - How does population size affect the likelihood of...Ch. 16 - If you measured the allele frequencies of a gene...Ch. 16 - 5. People like to say that “you can’t prove a...Ch. 16 - 6. Describe the three ways in which natural...Ch. 16 - What is sexual selection? How is sexual selection...Ch. 16 - In North America, the average height of adult...Ch. 16 - By the 1940s, the whooping crane population had...
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- In which of the following pairs do both evolutionary processes introduce new genetic variation into a population? a. natural selection and genetic drift b. mutation and gene flow c. natural selection and gene flow d. gene flow and genetic driftarrow_forwardYou are asked to assess whether a population of endangered salamanders can adapt to warming climate in their preferred habitat. The salamanders vary at a locus that determines adaptation to temperature, and the warming climate creates selection favoring one of two alleles at that locus. Drawing on what you know about natural selection and genetic drift, what information would you need to know about the salamanders to determine whether the allele that improves their adaptation to warmer climates will become fixed in the population? Strictly no plagiarism.arrow_forwardWhich type of selection is represented in a population of birds where a wing span of 2ft rather than 1ft or 3ft is more beneficial? Directional Disruptive Stabalizingarrow_forward
- As you know chimpanzees in neighboring groups in the forest show 4-5 times as much genetic difference as any two human populations. Is it reasonable to expect that trait that show genetic variation in humans, such as the structure of the hand and the brain, might show significant variation between chimpanzee populations? Why or why not?arrow_forwardDo you believe that because insect beak length has changed in opposite directions in the Florida and the Texas populations that we have stronger evidence that natural selection was acting directly on beak length in these populations? Or is it equally likely that natural selection is only acting on a trait correlated with beak length in the Florida and Texas populations?arrow_forwardIn the 1900s, the Florida panther population declined drastically due to hunting and habitat loss, and, by the mid-1990s, there were fewer than 30 Florida panthers left in the wild. What were the most likely consequences of this decline in population size on the frequency of genetic abnormalities, such as malformed testicles, in the remaining population? A. The frequency of genetic abnormalities decreased due to the weakest panthers being eliminated through natural selection. B. The frequency of genetic abnormalities increased due to an increased rate of migration of other panthers into the population. C. The frequency of genetic abnormalities increased due to the random loss of genetic diversity and increased inbreeding in small populations. D. The frequency of genetic abnormalities decreased because the concentration of adaptive alleles in the small population decreased as the population declined.arrow_forward
- if a population of jumping spiders consists of 40 females and 40 males, what is the effective population size? Give the appropriate equation and show your work. Will genetic drift be an important evolutionary force in this population? Why or why not? If your answer is "yes", what does genetic drift do to allele frequencies? If your answer is "no", name two forces other than genetic drift that might be important in determining allele frequencies. asaparrow_forwardWhat are two reasons why a selection limit is reached in which artificial selection no longer has an effect?arrow_forwardThe trait that natural selection “selects for” is lifetime Darwinian fitness. If relative matching of the moths to the background is determining fitness differences, is there any difference in other fitness components in the color morphs of Biston betularia that is influencing the direction of evolution in the three populations shown in the graph? Give a reason for your answer.arrow_forward
- Is there evidence that random genetic drift in the inbred Swedish population had led to a decline in mean fitness that was sufficient to cause the extinction of the population? Here, I am asking about the Swedish population before the outbred snakes were introduced. What is the evidence for a decline in mean fitness, if you believe this happened?arrow_forwardIn general, what is the effect of complete selection, migration and random genetic drift on the gene frequencies of the population? a. complete selection b. migration c. random genetic driftarrow_forwardIs each of the following examples due to directional, disruptive, balancing, or stabilizing selection? A. Polymorphisms in snail color and banding pattern as described. B. Thick fur among mammals exposed to cold climates C. Birth weight in humans D. Sturdy stems and leaves among plants exposed to windy climatesarrow_forward
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