1 SEM CARDLESS ACC W/RAVEN TEXT
12th Edition
ISBN: 9781265321062
Author: Raven
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Chapter 21, Problem 4S
Refer to figure 21.5, artificial selection in the laboratory. In this experiment, one population of Drosophila was selected for low numbers of bristles and the other for high numbers. Note that not only did the means of the populations change greatly in 35 generations, but also all individuals in both experimental populations lie outside the range of the initial population. What would happen if the direction of selection were reversed, such that a greater number of bristles was selected for in the low-bristle population, and vice versa? How would the rate of evolutionary change compare with that in the initial part of the experiment before selection was reversed?
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In Drosophila melanogaster, wing shape is an autosomal trait. Vestigal wing is recessive (v) to the dominant trait for the normal long wings (V). In a mainland source population, the allele frequency of v is 0.02 . A small, experimental population of 100 flies was introduced on an island and had 20 flies with vestigal wings and 40 heterozygotes. What are the allele frequencies of V and v in this introduced population? What proportion (%) of heterozygotes and homozygous recessive flies would you expect to see after a few generations of mating on this island? What phenomenon of population genetics does this experiment demonstrate?
p+q=1, p^2 + 2pq + q^2 = 1
In the fly speciation experiment described in class, Drosophila from a single culture was split into four isolated cultures, 2 raised on maltose food and two on starch food. After forty generations all possible crosses were done between maltose and starch flies and between the two starch populations. Flies from different food types had very low mating frequencies compared to flies from the same food type but flies from different starch populations only mated at a very slightly lower rate than flies from the same starch population. How would you interpret this finding?
Group of answer choices
A. allopatric speciation is more powerful than sympatric speciation
B. flies are incapable of evolution
C. drift causes divergence more rapidly than selection
D. sympatric speciation is more powerful than allopatric speciation
E. selection causes divergence more rapidly than drift
In the fly speciation experiment described in class, Drosophila from a single culture was split into four isolated cultures, 2 raised on maltose food and two on starch food. After forty generations all possible crosses were done between maltose and starch flies and between the two starch populations. Flies from different food types had very low mating frequencies compared to flies from the same food type but flies from different starch populations only mated at a very slightly lower rate than flies from the same starch population. How would you interpret this finding?
Chapter 21 Solutions
1 SEM CARDLESS ACC W/RAVEN TEXT
Ch. 21.1 - Prob. 1LOCh. 21.1 - Prob. 2LOCh. 21.2 - Prob. 1LOCh. 21.2 - Distinguish between demonstrating that evolution...Ch. 21.3 - Contrast the processes of artificial and natural...Ch. 21.3 - Prob. 2LOCh. 21.4 - Prob. 1LOCh. 21.4 - Prob. 2LOCh. 21.4 - Prob. 3LOCh. 21.5 - Explain the evolutionary significance of...
Ch. 21.5 - Prob. 2LOCh. 21.6 - Prob. 1LOCh. 21.6 - Prob. 2LOCh. 21.7 - Characterize the criticisms of evolutionary theory...Ch. 21.7 - Prob. 2LOCh. 21 - Suppose that a male with a beak depth of 10 mm...Ch. 21 - Prob. 1IQCh. 21 - Prob. 2IQCh. 21 - Prob. 3IQCh. 21 - Why might the evolutionary line leading to...Ch. 21 - Artificial selection is different from natural...Ch. 21 - Gaps in the fossil record a. demonstrate our...Ch. 21 - The evolution of modern horses (Equus) is best...Ch. 21 - Homologous structures a. are structures in two or...Ch. 21 - Convergent evolution a. is an example of...Ch. 21 - Prob. 6UCh. 21 - The possession of fine fur in 5-month human...Ch. 21 - In Darwins finches, a. occurrence of wet and dry...Ch. 21 - Prob. 2ACh. 21 - Convergent evolution is often seen among species...Ch. 21 - What conditions are necessary for evolution by...Ch. 21 - Explain how data shown in figure 21.2a and b...Ch. 21 - Prob. 3SCh. 21 - Refer to figure 21.5, artificial selection in the...Ch. 21 - The ancestor of horses was a small, many-toed...
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