BIOLOGY
12th Edition
ISBN: 9781260169614
Author: Raven
Publisher: RENT MCG
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Textbook Question
Chapter 20, Problem 4U
Stabilizing selection differs from directional selection because
a. in the former, phenotypic variation is reduced but the average phenotype stays the same, whereas in the latter both the variation and the mean phenotype change.
b. the former requires
c. intermediate
d. None of the choices is correct.
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Students have asked these similar questions
With stronger natural selection, was the more beneficial allele lost from these small populations?a) It was lost very frequently, and the strength of natural selection did not make any difference.b) It was never lost.c) It was lost a few times, but not very often, and it was lost less frequently under strong selection.d) It was lost a few times, and it was lost more frequently under strong selection.
What type of selection is representative of what would happen if the earth were to continually cool, and some bears, such as those with thin or no hair, moved south and other bears with very thick fur stayed up the north. In this type of selection event, both types of bears would be selected for.
(a)disruptive selection
(b)directional selection
(c)stabilizing selection
(d)sexual selection
When we take, say, 100 individuals of a species of beetle from the wild and place them in a new environment that is not so different that they are unable to thrive but different enough so that they are experiencing a new selective regime, say, a lower temperature, what typically happens?
A - Sexual selection causes some larvae to be able to survive in the cooler temperatures and other individuals to be unable to survive because they need warmer temperatures.
B - We are unable to measure phenotypic selection, presumably because we do not have much variation among individuals for how they handle temperature.
C - The founder event assures us that the new population will be strictly representative of the source population (especially if we took all the 100 from the same location rather that from throughout the range of the species).
D - The population evolves to be tolerant of the lower temperature; it can do this because of latent variation already in the 100 founding individuals.
E -…
Chapter 20 Solutions
BIOLOGY
Ch. 20.1 - Define evolution and population genetics.Ch. 20.1 - Prob. 2LOCh. 20.2 - Explain the HardyWeinberg principle.Ch. 20.2 - Describe the characteristics of a population that...Ch. 20.2 - Prob. 3LOCh. 20.3 - Define the five processes that can cause...Ch. 20.3 - Prob. 2LOCh. 20.4 - Prob. 1LOCh. 20.4 - Prob. 2LOCh. 20.4 - Demonstrate how the success of different...
Ch. 20.5 - Prob. 1LOCh. 20.5 - Prob. 2LOCh. 20.5 - Prob. 3LOCh. 20.6 - Define frequency-dependent selection, oscillating...Ch. 20.6 - Prob. 2LOCh. 20.7 - Define and contrast disruptive, directional, and...Ch. 20.7 - Prob. 2LOCh. 20.8 - Explain how experiments can be used to test...Ch. 20.9 - Prob. 1LOCh. 20.9 - Prob. 2LOCh. 20.10 - Prob. 2LOCh. 20 - If all white cats died, what proportion of the...Ch. 20 - Assuming that the values on the x-axis represent...Ch. 20 - Prob. 3DACh. 20 - Prob. 4DACh. 20 - Examine the index of copper tolerance on nonmine...Ch. 20 - Prob. 6DACh. 20 - Why are rare alleles particularly likely to be...Ch. 20 - Prob. 2IQCh. 20 - Prob. 3IQCh. 20 - Prob. 4IQCh. 20 - Prob. 5IQCh. 20 - Prob. 6IQCh. 20 - Prob. 7IQCh. 20 - Prob. 8IQCh. 20 - Prob. 9IQCh. 20 - Assortative mating a. affects genotype frequencies...Ch. 20 - When the environment changes from year to year and...Ch. 20 - Many factors can limit the ability of natural...Ch. 20 - Stabilizing selection differs from directional...Ch. 20 - Founder effects and bottlenecks are a. expected...Ch. 20 - Relative fitness a. refers to the survival rate of...Ch. 20 - For natural selection to result in evolutionary...Ch. 20 - Prob. 8UCh. 20 - In a population of red (dominant allele) or white...Ch. 20 - Genetic drift and natural selection can both lead...Ch. 20 - Prob. 3ACh. 20 - Prob. 4ACh. 20 - In Trinidadian guppies a combination of elegant...Ch. 20 - On large, black lava flows in the deserts of the...Ch. 20 - Based on a consideration of how strong artificial...
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